New Plant Products - RIRDC Completed Projects in 2001-2002 & Research in Progress as at June 2002

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RIRDC Completed Projects in 2001-2002 & Research in Progress as at June 2002
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To New Plant Productws Research in Progress

1.1 NEW PLANT PRODUCTS - COMPLETED PROJECTS
PROJECT NO.	PROJECT TITLE	RESEARCHER	PHONE	ORGANISATION

Native Foods

CFO-1A	Innovative products from Australian native foods	Mr. Michael Forbes-Smith	(02) 9385 5788	CRC for Food Industry Innovation
DAW-95A	The prospects of commercialising indigenous Boab tubers as vegetables	Mr. Peter Johnson	(08) 9166 4026	Department of Agriculture (WA)

Culinary Herbs, Spices and Beverages

CPA-1A	Generation of residue data to set MRLs for pesticides on culinary herbs	Mr. Peter Dal Santo	(03) 5439 5916	CPA Research Pty Ltd
CPE-1A	Nutritional requirements of coffee trees in northern New South Wales	Mr. John Zentveld	(02) 6687 1004	CAPE Australia

Extractive and Fibre Crops

AOL-3A	THE OLIVE PRESS - Australian Olive Association Magazine	Mr. John Egan	(02) 9863 8735	Australian Olive Association
DAV-163A	Increasing the export potential-opportunities for Australian garlic	Ms. Gisele Irvine	(03) 9210 9222	Department of Natural Resources & Environment (Vic)
UCQ-15A	Commercial viability of Senna tora gum production in Australia	A/Prof. Kerry Walsh	(07) 4930 9707	Central Queensland University
UCQ-16A	A new rural industry – Stevia – to replace imported chemical sweeteners	Prof. David Midmore	(07) 4930 9770	Central Queensland University

Fruit, Vegetables and Nuts

DAQ-251A	Enhancing fruit yield and quality of rambutan and longan by optimising irrigation and nutrition systems	Mr. Yan Diczbalis	(07) 4064 1130	Department of Primary Industries (Qld)
DNT-26A	Nutrition and irrigation management of rambutan for maximisation of yield and quality - Northern Territory	Mr. Chris Wicks	(08) 8999 2309	NT Department of Business, Industry and Resource Development
ZTR-1A	Durian germplasm evaluation for tropical Australia phase 1	Mr. Guiseppe Zappala	(07) 4067 5266	Zappala Tropicals Pty Ltd

Miscellaneous

CUT-6A

Acacia saligna as a fodder source for ruminants

Dr. Gaye Krebs

(08) 9690 1523

Curtin University of Technology

Native Foods

Project title: Innovative products from Australian native foods

RIRDC Project No. CFO-1A

Researcher: Michael Forbes-Smith and Jane Paton

Organisation: CRC for Food Industry Innovation
Department of Food Science and Technology, UNSW
SYDNEY NSW 2052

Phone: (02) 9385 5788

Fax: (02) 9385 9031

Email: M.forbes@unsw.edu.au; J.paton@unsw.edu.au

Objectives · Improve shelf-life, quality and safety of existing native foods and to identify and develop novel products from native foods
· Develop applications across the food industry leading to increase in demand for the raw material with subsequent growth of the Australian native food industry.

Background Australian native foods are presently marketed for their fresh, wild qualities both in Australia and overseas. However, the Australian native food industry now encounters marketing challenges. Unless sales are increased, an over supply of some native foods may occur. Establishing a market focus and developing new market sectors will be the key to ensure a profitable future of the native food industry.

Research
· Extension of postharvest shelf-life of fresh native herbs.
· Analysis and development of flavour components of native raw materials.
· Preservation of lemon myrtle oil; improved bread formulations containing akudjura.
· Microbiological analysis of dried native food products and investigation of natural strategies to improve microbiological safety.
· Evaluation of antioxidant activity of native food ingredients
· Evaluation of antimicrobial activity of native food ingredients.

Outcomes Storage at 0-5ºC together with selected MA packaging systems significantly improved shelf-life of warrigal greens, lemon myrtle leaf and mountain pepperleaf.
Chromatographic techniques (eg GC-MS) showed the importance the volatile aroma components, as well as sugars and acids from lemon myrtle, lemon aspen, wild lime and wattleseed, but sensory evaluation and product development also played an important aspect of the research.
Selected gums (eg. sodium alginate), pH regulation at 3.5 and microencapsulation of lemon myrtle oil extended freshness of lemon myrtle flavour in added value products, including carbonated beverages.
Mild heat treatment of akudjura to inhibit possible enzymic activity was considered a simple and practical method as the bread doughs containing the treated akudjura rose and held their shape over proofing.
Microbial numbers in native herbs and spices were low except aniseed myrtle, akudjura and Red Desert Seasoning. Acetic acid was determined the most effective fumigant for reducing microbial populations in Red Desert Seasoning.
The antioxidant activity of native thyme was associated with the presence of eugenol. Lemon aspen contained an antioxidant compound with a molecular mass calculated tentatively at 408 Da. Both native foods showed ability to reduce browning in guacamole or apple juice.
Compounds from native pepperberry containing antimicrobial activity have been isolated and characterised using MS techniques. Pepperberry extract showed capacity to reduce microbial growth in horticultural commodities.

Implications The enhanced penetration of novel bushfood ingredients from our research findings into the general food industry will indirectly contribute to a wider appreciation of our native resources as foods and food adjuncts. The social impact has relevance to collectors and producers of bushfoods, value adders and end-users. Beneficiaries could include wild harvesters such as Aboriginal communities, specialist industry nurseries, gourmet food processors and manufacturers, restaurants ranging from the novel to the sophisticated upmarket sector, and speciality food service groups and distributors.

Publications
Paton JE, Hiller K, Forbes-Smith M and Wootton M. The use of akudjura in bread (in draft form).
Forbes-Smith M and Paton JE. Modified atmosphere packaging of Australian native herbs (in draft form).

Project title: The prospects of commercialising indigenous Boab tubers as vegetables

RIRDC Project No. DAW-95A

Researcher: Mr Peter Johnson

Organisation: Department of Agriculture (WA)
Locked Bag No 4
BENTLEY DELIVERY WA 6983

Phone: (08) 9166 4026

Fax: (08) 9166 4066

Email: johnsonp@agric.wa.gov.au

Objectives · To conduct a primary investigation into Boab tuber to determine its commercial potential. Provide an information package as the basis to establish an industry, thereby reducing the risk for investors and primary producers.

Background The Australian boab Adansonia gregorii is indigenous to the Kimberley region of Western Australia. Although the tree is recognised for its iconic value amongst non-indigenous Australians it is well known amongst the indigenous populations of the Kimberley as a tree with a vast array of uses including food, medicine and shelter.
Adansonia gregorii is closely related to eight other Adansonia species found in Africa and Madagascar. These related species have also long been used a regular food source by the indigenous populations of Africa forming part of the staple diet. Studies on the African species have identified parts of the tree being rich in Vitamin C (ten fold that of oranges) and Vitamin A. However in spite of this Adansonia gregorii has to the most part been over looked for its potential commercial value. Although some enthusiastic local residents in the Kimberley region of WA have been cultivating the tree.

Research
The purpose of this study is to have a preliminary evaluation of the Boab roots to assess its potential as a cultivated vegetable crop. The study examined the chemical composition of the crop, which has identified no known toxic compounds exist in the roots. The nutritional breakdown has identified the roots are rich in Potassium and are a moderate source of starch and sugars.

Outcomes Small-scale trial plantings gave mixed results with excellent germination during the wet season and very poor germination during the dry season. Trialing various techniques to improve germination identified that a sulphuric acid dip and manual scarification of the seed gave improved results.
Samples from the initial trials were sent to the Hyatt hotel in Perth for an assessment by the chefs for its culinary potential. This was combined with a promotion that was featured on a Channel nine documentary giving the project high profile. Feed back from the assessment was very positive both from the chefs and the consumers. Whilst conducting the assessment a post harvest breakdown of the product was identified, when stored at higher temperatures. Rapid cooling to 5 to 7 degrees Celsius post harvest rectified this problem. The assessment also identified wide spread interest in the leaves as a salad vegetable.
Larger scale trials identified that seed extraction, planting and harvesting can be mechanised thus keeping the production costs at a minimum. These trials examined several different pre seed treatments and the benefits of incorporating fertiliser at planting. Interestingly the sulphuric acid gave poor results in this trial, which is believed to be due to the timing of the treatment. Twelve-month-old seed and double density planting gave the highest results. Extrapolating these results gives to 18-20 tonnes per hectare of marketable product. The addition of fertiliser did not significantly improve the yields. Weed control during the first few weeks of planting presents a problem and will require further evaluation of herbicides.
The economic analysis has identified the seed represents the largest single production cost. The analysis based on yields of 8.9 t/ha and a price of $5.00kg gives a gross margin of $22,267 ha. The sensitivity analysis indicates that the break-even price per kg at 8.9t/ha is $3.01 and at 13.3t/ha is $2.47/Kg. Improved germination rates has a significant positive effect on the gross margin.

Implications The prospects for commercialising the crop look very promising with positive market response for the roots and leaves, the ability to mechanise production, short production time 6 to 8 weeks and a favourable economic analysis. The major limiting factors initially with developing an industry is securing a seed supply (time taken to establish a seed stock.) and undertaking the promotion required to introduce the product to the wider community.

Publications
The prospect of commercialising Boab roots as a vegetable, RIRDC Publication No. 02/020, 29 pgs, 2002

Culinary herbs, spices and beverages

Project title: Generation of residue data to set MRLs for pesticides on culinary herbs

RIRDC Project No.: CPA-1A

Researcher: Mr Peter Dal Santo

Organisation: CPA Research Pty Ltd
Level 1, 5 Everage Street
MOONEE PONDS VIC 3039

Phone: (03) 5439 5916

Fax: (03) 5439 3391

Email: pdalsanto@cpaltd.com.au

Objectives · Ensure culinary herb growers continue to have market access by providing pesticide residue information required to obtain long term permits for pesticides considered essential for economic production.

Background Culinary herbs have been produced in volume in Australia for many years and growers have assumed pesticides registered for use on leafy vegetables could legally be used on culinary herbs. The food safety initiative of ANZFA, and commercial requirements led to inquiries with the National Registration Authority (NRA) which showed that culinary herb growers would not be able to use pesticides unless permits were obtained specifically authorising the uses.
This project was established to obtain minor use permits for the use of the following products on herbs: Pirimor (pirimicarb), Bugmaster (carbaryl), Ambush (permethrin), Ridomil Gold (metalaxyl + mancozeb) and Select (clethodim).

Research Residue trials were conducted on coriander, dill, garlic chives, sorrel and thyme. The trials were established on schedule and treatments were applied. Residue samples were despatched to the analytical laboratory. The detailed protocols and results of the field experiments and laboratory analyses are provided in the appendix.
The analytical laboratory experienced great difficulty in analysing the samples, because of the high concentration of essential oils in the plants. This problem delayed the delivery of analytical results for several months until a suitable methodology was developed.
The results of the trials were incorporated into applications for permits that were despatched to the NRA 0n 20/6/2002.

Outcomes One Permit Per5675 for Select has been cleared by the NRA. The others are pending. RIRDC and the herb growers will be notified when they are issued.

Implications When issued, the permits will enable the herb growers to legally use the products to improve their crop protection programs against insects and weeds.

Publications None

Project title: Nutritional requirements of coffee trees in northern New South Wales

RIRDC Project No.: CPE-1A

Researcher: Mr. John Zentveld

Organisation: CAPE Australia
179 Broken Head Road
NEWRYBAR NSW 2479

Phone: (02) 6687 1004

Fax: (02) 6687 1335

Email: cape@zentvelds.com.au

Objectives · To establish optimal nutritional requirements of Arabica coffee grown under sub-tropical conditions in northern New South Wales for sustainable yields of high quality coffee using N.P.K fertilisers together with leaf and soil analysis.

Background The coffee industry in northern New South Wales is a relatively new industry. Established by farmers seeking to diversify or redirect their crop base in the early 1990s, it was discovered that little was known about the nutritional requirements of the coffee trees. Consequently RIRDC was approached with the view that they fund research into the nutritional requirements of Arabica coffee trees for the embryonic coffee industry.
It was felt that this research would assist existing coffee farmers in maximising crop yields. It was felt also the scientific research would serve to encourage new growers to enter into the industry therefore increasing the possibility of creating a future export commodity as well as assisting in satisfying the growing Australian demand for gourmet coffee.

Research In essence, four different fertiliser combinations (consisting of different combinations of phosphorus, nitrogen and potassium) were applied to newly planted coffee trees. The height of these trees was measured throughout the study period to provide an indication of tree growth in response to the differing fertiliser combinations.

Outcomes Analysing the tree growth during the period it was found that there was little or no difference in tree height between the four different treatments irrespective of the differing nutrient treatments.

Implications It is possible that the application of phosphorous by hand in solid particle form throughout the trial block may have reduced actual uptake rates by the coffee trees in dry weather. Coffee tree growth increased dramatically between the months of September 2001 and March 2002. This closely coincided with the introduction of fertigation equipment on the farm, whereby nutrients applied to the trial (excluding phosphorus) were done so via fertigation. However, as only one growth measurement of the coffee trees was taken following the introduction of the fertigation equipment, there is no direct evidence for such a relationship. Therefore such a conclusion that fertigation increases the growth of coffee trees is purely speculative. As such, more research needs to be undertaken in this area to determine if a relationship exists.

Publications Nutritional requirements of coffee trees in northern New South Wales, RIRDC Research Report No. 02/102 (in press)

Extractive and fibre crops

Project title: THE OLIVE PRESS - Australian Olive Association Magazine

RIRDC Project No.: AOL-3A

Researcher: Mr John Egan

Organisation: Australian Olive Association
PO Box 309
PENDLE HILL NSW 2145

Phone: (02) 9863 8735

Fax: (02) 9636 4971

Email: secretariat@australianolives.com.au

Internet: www.australianolives.com.au

Objectives · The Olive Press is to be the principal communications forum for the olive industry, and as such to have a significant and positive impact on the development potential of the infant Australian olive industry and ultimately on its success as a significant import replacement and exporting industry.

Background In 1998 the Australian Olive Association Board recognised the need for a quality industry specific magazine to serve the needs of a new emerging industry. The project was to develop the Association’s existing newsletter into a professionally produced and independently edited magazine covering all aspects of the olive industry. However, financing the project at that stage of the Association’s and the industry’s development was not possible. RIRDC provided financial support over three years for the production of The Olive Press, the official journal of the Australian Olive Association.

Research The Olive Press is the primary vehicle for disseminating research and technical reports and articles direct to all stakeholders in the Australian olive industry and complementary copies are sent to various individuals and institutions overseas.

Outcomes The magazine disseminates all forms of industry information – research and technical; industry developments, issues and news; new products and technology; book reviews; health issues; letters to the editor; and nationwide industry specific advertising. The magazine continues to grow with each issue and consolidate its position as the premier publication supporting the sustainable growth and development of the emerging Australian olive industry.

Implications The primary implication of The Olive Press is that it has provided all participants in the olive industry with a reliable and objective source of information and provided a forum for open debate of pertinent industry issues. The publication has also served to enhance the image and credibility within the industry of its peak body, The Australian Olive Association.

Publications The Olive Press is produced quarterly - Summer, Autumn, Winter and Spring issues. The first issue was the Summer 1998 (December).

Project title: Increasing the export potential-opportunities for Australian garlic

RIRDC Project No.: DAV-163A

Researcher: Gisele Irvine and Samantha Sterling

Organisation: Department of Natural Resources & Environment (Vic)
Institute for Horticultural Development
Private Bag 15
SCORESBY BUSINESS CENTRE, VICTORIA 3176

Phone: (03) 9210 9222

Fax: (03) 9800 3521

Email: Gisele.Irvine@nre.vic.gov.au, Sam.Sterling@nre.vic.gov.au

Objectives · To provide information on the yield benefits and pharmaceutical quality of virus-tested garlic to allow the Australian garlic industry to access new market opportunities and increase productivity to meet the demands of those markets.

Background Currently, the garlic industry in Australia is small (350 tonnes per annum in the three years prior to 1995) and targeted primarily at the domestic (fresh) market. Imports are significant, totalling 2,500 tonnes in 1996 and often cheaper than the local product (coming from China, the USA and Argentina). These imported products flood the market reducing prices. The Australian Garlic Industry Association (AGIA) has collaborated with IHD, Knoxfield on two prior RIRDC-funded programs: BIO-1A, aimed at increasing productivity by reducing yield losses from virus (development of virus-tested seed stock), and DAV-124A, aimed at identifying new market opportunities for Australian garlic as a pharmaceutical product based on the level of bioactive compounds (alliin) within the bulb.
The success of these programs led to a rapid expansion in the Australian garlic industry (1200 tonnes expected harvest in 1998, from 130 hectares). Further expansion of the industry is dependent on the availability of the virus-tested seed stock and markets available for the pharmaceutical grade product. The AGIA, in conjunction with commercial interests, sought evaluation of the virus-tested seed stock, both with respect to its alliin levels (pharmaceutical quality) and purported yield increases. Clear definition of the potential benefits were considered essential to enable industry to exploit new international markets based on pharmaceutical interests.

Research Field trials were conducted at the Sunraysia Horticultural Centre as a central region for Victorian, South Australian and NSW interest's over a period of two years. Virus-tested and commercial garlic was grown under aphid-proof screenhouses and also under commercial conditions to evaluate yield differences, re-infection rates and alliin levels. Alliin levels were investigated for all the cultivars and under all the field trial conditions. Viruses known to affect garlic yields are Onion Yellow Dwarf Virus (OYDV), Leek Yellow Stripe Virus (LYSV) and Shallot Latent Virus (SLV), when in combination with either or both of the former two viruses.

Outcomes The outcomes of this project have been the evaluation of the virus-tested garlic cultivars. Some of these cultivars gave consistently higher yields than the industry standards, under two very different climatic seasons. The study indicated that infection of garlic by yield reducing viruses does occur in the first year of commercial planting given a source of virus and winged aphid colonies. The alliin level of the virus-tested garlic was found to be not significantly higher than the industry standard material, but the yield increases of some virus-tested cultivars allow a greater amount of alliin to be produced per hectare.

Implications This project has indicated that higher yields can be gained by planting particular virus-tested garlic cultivars and that higher yields can be seen as being economically attractive in the commercial production of alliin given reliable markets and adequate monetary returns from these markets.

Publications Irvine and Sterling, 1999,2000,2001 Australian Garlic Industry Association Seminar Proceedings.
Increasing the export potential-opportunities for Australian garlic, RIRDC Research Report No. 02/096, 26 pgs, 2002

Project title: Commercial viability of Senna tora gum production in Australia

RIRDC Project No.: UCQ-15A

Researcher: Kerry Walsh and David Cunningham

Organisation: Plant Sciences Group
School of Biological and Environmental Sciences
Central Queensland University
ROCKHAMPTON QLD 4702

Phone: Kerry Walsh (07) 4930 9707

Fax: Kerry Walsh (07) 4930 6536

Email: k.walsh@cqu.edu.au, davidcunningham@ozemail.com.au

Internet: science.cqu.edu.au/psg

Objectives · Assess potential for food gum production from Senna tora
· Source and multiply seed of known provenance
· Use yield data in economic analysis
· Recommend on feasibility of production.

Background Seed gums are classed as a "thickener/vegetable gum" in foods and are also used in a range of non-food applications including textile and paper manufacturing. The main sources of seeds gums on the world market are carob (locust bean) and guar, an increasingly important gum is sourced from Senna tora and Senna obtusifolia in India. Australia currently imports all of its seed gum requirements. S. tora and S. obtusifolia are established in Australia as weeds, infesting approximately 600,000 ha in coastal north and far north Queensland. The patent for the use of S. tora/obtusifolia gum in conjunction with carrageenan, the main use of the product in canned pet foods, will expire in September 2003. As the patent expires, industry users will encourage production in areas other than India to diversify supply options. It is therefore strategic to consider the potential for production of this gum in Australia at this time.

Research · Literature review on the potential for production of Senna tora
· Senna tora seed location and sourcing
· Field and glasshouse trials to multiply seed and estimate yields
· Assessment of economic feasibility of cropping Senna tora in Australia.

Outcomes · Literature review on the potential for production of Senna tora
· Senna tora seed was sourced within Australia and multiplied in glasshouse trials
· Glasshouse and field yield estimates were low, too low to support a viable industry on a return of $250/tonne seed in the economic model used. However, higher yields are reported overseas and should be possible here, given attention to agronomy and cultivars.

Implications Given attention to agronomy and cultivars, a commercial industry could be established in Australia. A growers group could negotiate with pet food industry users regarding contract pricing. However, establishment of an industry in Queensland would require legislation change with respect to the weed status of these species. Sourcing seed stock from all international distributions to establish a breeding program is advised.

Publications Cunningham DC, Walsh KBW (2001) ‘Viability of Senna tora gum production in Australia.’ RIRDC Research Report No. 01/131, 34 pgs, 2001.
Cunningham D (2001) Seed gums in Australian food processing. Food Australia 53, 209-212.
Cunningham DC (2000) Commercial viability of Senna tora galactomannan production under Australian conditions. In ‘Autecology of Cassia brewsteri with respect to galactomannan production’, pp. 223-263. PhD Thesis, Central Queensland University, Rockhampton.

Project title: A new rural industry – Stevia – to replace imported chemical sweeteners

RIRDC Project No.: UCQ-16A

Researcher: Prof. David Midmore Mr. Andrew Rank

Organisation: Central Queensland University
Plant Sciences Group
Bruce Highway
NORTH ROCKHAMPTON QLD 4702

Phone: (07) 4930 9770 (07) 4930 6870

Fax: (07) 4930 9255 (07) 4930 9255

Email: d.midmore@cqu.edu.au a.rank@bigpond.com.au

Internet: http://www.ahs.cqu.edu.au/info/science/psg/

Objectives · To review overseas literature on Stevia and visit industry representatives in China and Japan to determine the relevance of information for potential establishment of a Stevia industry in Australia.
· To bring stakeholders in a potential Stevia industry together to review findings and determine whether to proceed with further R & D.

Background As a natural sweetener, commercial production of Stevia in Australia could lead to a reduction in the import of c. $12.0 million as artificial sweeteners. It could contribute to the well-being of diabetics, and others wishing to reduce sugar intake.

Research Outcomes Visits to Japan and China were conducted and after presentation of information collected, and that from the literature review, to parties interested in Stevia, it was decided to proceed with further R & D on two parallel fronts. One, to establish and address the requirements for ANZFA approval of steviosides for use in the food industry, and the other to develop cost-effective production and processing protocols for a successful Australian industry. Should either of these show no reasonable progress within one year of a new RIRDC/University/stakeholder project, then further activities will cease. The support of all potential stakeholders (including the Health Industry) will be canvassed.

Implications If successful, the further R & D will lay the foundation of an industry providing a nature sweetener to the predicted 1 in 4 Australians who will develop diabetes over their lifetime. It will also contribute to the general well-being and weight consciousness of many Australians.

Publications --

Fruit, vegetables and nuts

Project title: Enhancing fruit yield and quality of rambutan and longan by optimising irrigation and nutrition systems

RIRDC Project No.: DAQ-251A

Researcher: Yan Diczbalis

Organisation: Department of Primary Industries
Queensland Horticulture Institute
PO Box 20
SOUTH JOHNSTONE QLD 4859

Phone: (07) 4064 1130

Fax: (07) 4064 2249

Email: Yan.Diczbalis@dpi.qld.gov.au

Objectives · The project aims were to monitor changes in longan and rambutan leaf and soil nutrient status over three seasons, measure grower fertiliser inputs in relation to the above, assess the effect of nutrient status on productivity, monitor tree phenology in relation to climate and irrigation management and quantify longan water/irrigation requirements.

Background The Australian longan and rambutan industries, together with DPI, NT DPIF and RIRDC and other bodies have, over the last few years engaged in detail assessments of industry research and development needs. Industry strategic plans have been developed for the longan industry (Anon 1998) and a commitment to support research has been made by the relevant organizations. The longan and rambutan industries had identified nutrition and irrigation research as a priority issue.

Research The project was unable to identify any direct links between tree nutritional status, fertiliser inputs and yield. Its important to note that all commercial orchards surveyed had relatively high leaf nutrient status and no unfertilised trees were included in the study. This suggests that within the range of nutrient status observed other factors such as pruning practices and climate play a more important role in flowering and subsequent yield. Despite the lack of relationship between nutrient status and yield, the survey of longan orchards indicated that high leaf N levels (N ³ 1.9%) during the period leading up to flowering should be avoided because it may be detrimental to flowering and hence subsequent cropping. Tentative leaf and soil standards were developed to use as a guide to fertiliser management.

Outcomes A guide to fertiliser requirements was developed using a nutrient budget approach where nutrient inputs are based on fruit production and removal and take into account additional nutrient loss via leaching, runoff and fixation.

Implications As a result of the development of a nutrient budget, inputs can now be geared to production rather then based on an ad-hoc approach. This allows for potential savings on fertiliser inputs, however, more importantly the nutrient budget approach has the potential to reduce fertiliser loss and hence contamination of sub-soils and drainage systems.

Publications Nil publications. Presentations made to industry.

Project title: Nutrition and irrigation management of rambutan for maximisation of yield and quality - Northern Territory

RIRDC Project No.: DNT-26A

Researcher: Chris Wicks

Organisation: Northern Territory Department of Business, Industry and Resource Development
Horticulture Division
Berrimah Agricultural Research Centre
GPO Box 3000
DARWIN NT 0801

Phone: (08) 8999 2309

Fax: (08) 8999 2049

Email: chris.wicks@nt.gov.au

Objectives · The project will improve our understanding of nutrient and irrigation management in rambutan, with particular emphasis on management through the fruit filling stage. This will lead to improved yield and fruit quality with more efficient use of fertiliser and irrigation inputs and hence increased profitability. The monitoring and reporting components of the project are closely linked with industry participation hence the uptake of new findings will be rapid and lead to improvements in productivity.

Background The research program intends to monitor fertiliser and irrigation inputs, with particular emphasis during fruit development. The performance of orchards where regular "fertigation" is practiced will be compared to those where fertiliser is applied conventionally. The irrigation monitoring component will be used as an extension tool to develop increased awareness of the benefits of irrigation scheduling and to introduce growers to a range of soil moisture monitoring devices. The project will run in conjunction with the NT Rambutan Growers Group, a subgroup of the NT Horticultural Association.

Research A new set of critical ranges has been developed for rambutan leaf and soil nutrition in the NT. These ranges were developed using a process called DRIS analysis in conjunction with statistical analysis of 13 sets of samples gathered from each of 15 different properties over a 36 month period. This nutrition data was also used to look for any differences between trees that had fertiliser applied by fertigation or by broadcast. While there were significant differences in both soil and leaf nutrient levels, there was no clear distinction between fertiliser systems. An attempt to link nutrient inputs to productivity was unsuccessful due to climatic influences severely restricting yields during the project. The analysis of water inputs showed that some properties had irrigation levels that were significantly different from the recommended levels. A great amount of workshopping and one-to-one information sessions were held.

Outcomes A new set of critical ranges has been developed for rambutan leaf and soil nutrition in the NT. The decision making process for using fertigation or broadcast to fertilise rambutan has become clearer with there being no clear nutritional benefit or detriment and so any decision can be made on economic or management grounds.
The ongoing analysis of irrigation inputs and soil water convinced 7 growers to begin using soil water monitoring equipment themselves.

Implications The improved nutrition standards and the increased uptake by growers of soil water monitoring equipment should see an improvement in tree productivity and a decrease in inputs. Thus improving profitability.
However the severe influence of climate seen over during the project suggests quite strongly that further work be carried out in the NT on the influence on environment on flowering and fruit retention.

Publications Durian Germplasm Evaluation for Tropical Australia, RIRDC Research Report No. 02/106 (in press)

Project title: Durian germplasm evaluation for tropical Australia phase 1

RIRDC Project No.: ZTR-1A

Researcher: Mr. Guiseppe Zappala

Organisation: Zappala Tropicals Pty. Ltd.
CMB. No 61
Deeral, via CAIRNS QLD 4871

Phone: (07) 4067 5266

Fax: (07) 4067 5315

Email: zappala@iig.com.au

Objectives · The introduction of the best durian clones of Asia from guaranteed budwood sources.
· Propagation of these clones (single and multi-rootstocked) with the best nursery practices.
· Development of an industry strategic plan
· To compare growth rates and performances under different clonal tolerances to pests, diseases and strong winds.
· To identify clones best suited for Phase 2 (Yield and Fruit Quality Assessment) for future Australian planting and export potential.

Background Durian (Durio zibethinus Murray) is indigenous to the hot equatorial rainforest of Malaysia and Indonesia. Australia currently imports up to 500 tonnes of frozen durian. Australian fresh durian is popular in our domestic markets and the export potential is good. Our industry must be based on clones that produce quality fruit under local climatic conditions. This five-year project evaluated the responses of 30 newly imported Asian durian clones to the north Queensland tropical climate.

Research During the clonal evaluation period, project trees were exposed to extreme weather patterns with regular cyclones, annual rainfall in excess of 6000mm and cold temperatures as low as 5°C. Clonal survival observations from these climatic conditions, combined with six rounds of tree measurements and early flowering and fruit yield data, were used to select the top seven new clones.

Outcomes Hepe, D. macrantha, D 175 (Red Prawn), DPI Mon Thong, Hawaiian Mon Thong, D 190 and Kradum Thong are the seven new clones highly recommended. Two clones on the current recommended Australian planting list, Kan Yao and Australian Luang were included as "standards" for comparison purposes. The Hawaiian Mon Thong No 315 performed well with an estimated fruit yield of 140 kg from this 10-year-old tree.

Implications The new clones Hepe, D. macrantha, D 175 (Red Prawn), DPI Mon Thong, Hawaiian Mon Thong, D 190 and Kradum Thong will provide a 175% increase to Australia’s current recommended planting list. These additional planting choices provide growers with the confidence required to move forward for industry expansion in tropical Australia and will ensure that our high value horticultural industry contributes to the Australian economy.

Publications Zappala, G., Zappala, A. J., and Diczbalis, Y. 2002 "Durian Germplasm Evaluation for Tropical Australia. Phase 1." RIRDC Research Report No. 02/091, Rural Industries Research and Development Corporation, Canberra, February 2002 p147.
Zappala, A. J. "Australian Durian Industry Strategic Plan." 2001-2006. RIRDC Web Publication W02/016, Rural Industries Research and Development Corporation, Canberra, February 2002.

Miscellaneous

Project title: Acacia saligna as a fodder source for ruminants

RIRDC Project No.: CUT-6A

Researcher: Dr Gaye Krebs

Organisation: Curtin University of Technology
Muresk Institute of Agriculture
NORTHAM WA 6401

Phone: (08) 9690 1523

Fax: (08) 9690 1500

Email: g.krebs@curtin.edu.au

Objectives · To determine the usefulness of Acacia saligna as an environmentally sustainable addition to the grazing system. In the first instance this involves determining the nutritive value of A. saligna as a fodder source for ruminants.

Background Land degradation is an issue of major concern in Australia. Overgrazing can be caused by continuous overstocking, but may also result from short-term overstocking that occurs in many areas which experience a feed shortage/deficit during the summer/autumn period. A saligna represents a fodder source which potentially may be utilised during the summer/autumn feed deficit period.
The common conclusion drawn by researchers regarding the value of A. saligna is that it is inadequate as the ruminant’s sole source of nutrients. This is largely attributed to its condensed tannin content. Environmental factors also affect the nutritive value of various browse species, and thus there was a need to determine the nutritive value of A. saligna grown in the Mediterranean climate of Western Australia.

Research Three pen trials, together with a laboratory-base trial, were conducted to evaluate the usefulness of A. saligna as a source of feed for ruminants. The feeding trials involved providing sheep (or goats) with A. saligna as either the sole or supplemental source of nutrients and measuring animal production responses (feed intake, wool growth, etc) and metabolic responses (nitrogen balance, rumen pH, dry matter and organic matter digestiblity). The laboratory-based trial involved determining the effects of maturity and season on the nutritive value of A. saligna.

Outcomes Many factors affect the nutritive value of A. saligna and as a consequence the nutritive value of this material is highly variable. At times it is far from acceptable as a feed source, at other times it can meet the maintenance (feed) requirements of both sheep and goats (goats do not have superior ability than sheep in utilising A. saligna as a source of nutrients).
Results indicate that generally as the plant matures, its nutritive value declines, however, this season in which the A. saligna is lopped (initially grazed) appears to confound this effect. Regrowth from spring lopped A. saligna generally has a higher nutritive value than regrowth from autumn or winter lopped trees, although this difference becomes much less pronounced as the plant matures.

Implications The research has indicated that under certain circumstances/conditions A. saligna would be a useful addition to a potentially environmentally sustainable grazing system. However, there is a need to investigate the circumstances that predispose A. saligna to becoming a high-tannin feed, subsequently lowering its feed value.

Publications Howard, D., Krebs, G.L. & van Houtert, M (in press) The value of Acacia saligna as source of feed for sheep. Proceedings of the Acacia Symposium, held at Dalwallinu, WA, 13-14 July 2001 (refereed proceedings).
Accepted: Krebs, G.L. and May, D. The effect of season and age of regrowth on the nutritive value of A. saligna (Rangelands Conference, Kalgoorlie, Sept 2002)
Howard, D.M. (2002) The Value of Acacia saligna as a Source of Fodder for Ruminants, Masters Thesis, Curtin University of Technology
May, D. (2001) The Effect of Age of Regrowth and the Season of Cutting on the Nutritive Value of Acacia saligna, Honours Dissertation, Curtin University of Technology.

Project title:	Innovative products from Australian native foods
RIRDC Project No.	CFO-1A
Researcher:	Michael Forbes-Smith and Jane Paton
Organisation:	CRC for Food Industry Innovation Department of Food Science and Technology, UNSW SYDNEY NSW 2052
Phone:	(02) 9385 5788
Fax:	(02) 9385 9031
Email:	M.forbes@unsw.edu.au; J.paton@unsw.edu.au
Objectives	· Improve shelf-life, quality and safety of existing native foods and to identify and develop novel products from native foods · Develop applications across the food industry leading to increase in demand for the raw material with subsequent growth of the Australian native food industry.
Background	Australian native foods are presently marketed for their fresh, wild qualities both in Australia and overseas. However, the Australian native food industry now encounters marketing challenges. Unless sales are increased, an over supply of some native foods may occur. Establishing a market focus and developing new market sectors will be the key to ensure a profitable future of the native food industry.
Research	· Extension of postharvest shelf-life of fresh native herbs. · Analysis and development of flavour components of native raw materials. · Preservation of lemon myrtle oil; improved bread formulations containing akudjura. · Microbiological analysis of dried native food products and investigation of natural strategies to improve microbiological safety. · Evaluation of antioxidant activity of native food ingredients · Evaluation of antimicrobial activity of native food ingredients.
Outcomes	Storage at 0-5ºC together with selected MA packaging systems significantly improved shelf-life of warrigal greens, lemon myrtle leaf and mountain pepperleaf. Chromatographic techniques (eg GC-MS) showed the importance the volatile aroma components, as well as sugars and acids from lemon myrtle, lemon aspen, wild lime and wattleseed, but sensory evaluation and product development also played an important aspect of the research. Selected gums (eg. sodium alginate), pH regulation at 3.5 and microencapsulation of lemon myrtle oil extended freshness of lemon myrtle flavour in added value products, including carbonated beverages. Mild heat treatment of akudjura to inhibit possible enzymic activity was considered a simple and practical method as the bread doughs containing the treated akudjura rose and held their shape over proofing. Microbial numbers in native herbs and spices were low except aniseed myrtle, akudjura and Red Desert Seasoning. Acetic acid was determined the most effective fumigant for reducing microbial populations in Red Desert Seasoning. The antioxidant activity of native thyme was associated with the presence of eugenol. Lemon aspen contained an antioxidant compound with a molecular mass calculated tentatively at 408 Da. Both native foods showed ability to reduce browning in guacamole or apple juice. Compounds from native pepperberry containing antimicrobial activity have been isolated and characterised using MS techniques. Pepperberry extract showed capacity to reduce microbial growth in horticultural commodities.
Implications	The enhanced penetration of novel bushfood ingredients from our research findings into the general food industry will indirectly contribute to a wider appreciation of our native resources as foods and food adjuncts. The social impact has relevance to collectors and producers of bushfoods, value adders and end-users. Beneficiaries could include wild harvesters such as Aboriginal communities, specialist industry nurseries, gourmet food processors and manufacturers, restaurants ranging from the novel to the sophisticated upmarket sector, and speciality food service groups and distributors.
Publications	Paton JE, Hiller K, Forbes-Smith M and Wootton M. The use of akudjura in bread (in draft form). Forbes-Smith M and Paton JE. Modified atmosphere packaging of Australian native herbs (in draft form).

Project title:	The prospects of commercialising indigenous Boab tubers as vegetables
RIRDC Project No.	DAW-95A
Researcher:	Mr Peter Johnson
Organisation:	Department of Agriculture (WA) Locked Bag No 4 BENTLEY DELIVERY WA 6983
Phone:	(08) 9166 4026
Fax:	(08) 9166 4066
Email:	johnsonp@agric.wa.gov.au
Objectives	· To conduct a primary investigation into Boab tuber to determine its commercial potential. Provide an information package as the basis to establish an industry, thereby reducing the risk for investors and primary producers.
Background	The Australian boab Adansonia gregorii is indigenous to the Kimberley region of Western Australia. Although the tree is recognised for its iconic value amongst non-indigenous Australians it is well known amongst the indigenous populations of the Kimberley as a tree with a vast array of uses including food, medicine and shelter. Adansonia gregorii is closely related to eight other Adansonia species found in Africa and Madagascar. These related species have also long been used a regular food source by the indigenous populations of Africa forming part of the staple diet. Studies on the African species have identified parts of the tree being rich in Vitamin C (ten fold that of oranges) and Vitamin A. However in spite of this Adansonia gregorii has to the most part been over looked for its potential commercial value. Although some enthusiastic local residents in the Kimberley region of WA have been cultivating the tree.
Research	The purpose of this study is to have a preliminary evaluation of the Boab roots to assess its potential as a cultivated vegetable crop. The study examined the chemical composition of the crop, which has identified no known toxic compounds exist in the roots. The nutritional breakdown has identified the roots are rich in Potassium and are a moderate source of starch and sugars.
Outcomes	Small-scale trial plantings gave mixed results with excellent germination during the wet season and very poor germination during the dry season. Trialing various techniques to improve germination identified that a sulphuric acid dip and manual scarification of the seed gave improved results. Samples from the initial trials were sent to the Hyatt hotel in Perth for an assessment by the chefs for its culinary potential. This was combined with a promotion that was featured on a Channel nine documentary giving the project high profile. Feed back from the assessment was very positive both from the chefs and the consumers. Whilst conducting the assessment a post harvest breakdown of the product was identified, when stored at higher temperatures. Rapid cooling to 5 to 7 degrees Celsius post harvest rectified this problem. The assessment also identified wide spread interest in the leaves as a salad vegetable. Larger scale trials identified that seed extraction, planting and harvesting can be mechanised thus keeping the production costs at a minimum. These trials examined several different pre seed treatments and the benefits of incorporating fertiliser at planting. Interestingly the sulphuric acid gave poor results in this trial, which is believed to be due to the timing of the treatment. Twelve-month-old seed and double density planting gave the highest results. Extrapolating these results gives to 18-20 tonnes per hectare of marketable product. The addition of fertiliser did not significantly improve the yields. Weed control during the first few weeks of planting presents a problem and will require further evaluation of herbicides. The economic analysis has identified the seed represents the largest single production cost. The analysis based on yields of 8.9 t/ha and a price of $5.00kg gives a gross margin of $22,267 ha. The sensitivity analysis indicates that the break-even price per kg at 8.9t/ha is $3.01 and at 13.3t/ha is $2.47/Kg. Improved germination rates has a significant positive effect on the gross margin.
Implications	The prospects for commercialising the crop look very promising with positive market response for the roots and leaves, the ability to mechanise production, short production time 6 to 8 weeks and a favourable economic analysis. The major limiting factors initially with developing an industry is securing a seed supply (time taken to establish a seed stock.) and undertaking the promotion required to introduce the product to the wider community.
Publications	The prospect of commercialising Boab roots as a vegetable, RIRDC Publication No. 02/020, 29 pgs, 2002

Project title:	Generation of residue data to set MRLs for pesticides on culinary herbs
RIRDC Project No.:	CPA-1A
Researcher:	Mr Peter Dal Santo
Organisation:	CPA Research Pty Ltd Level 1, 5 Everage Street MOONEE PONDS VIC 3039
Phone:	(03) 5439 5916
Fax:	(03) 5439 3391
Email:	pdalsanto@cpaltd.com.au
Objectives	· Ensure culinary herb growers continue to have market access by providing pesticide residue information required to obtain long term permits for pesticides considered essential for economic production.
Background	Culinary herbs have been produced in volume in Australia for many years and growers have assumed pesticides registered for use on leafy vegetables could legally be used on culinary herbs. The food safety initiative of ANZFA, and commercial requirements led to inquiries with the National Registration Authority (NRA) which showed that culinary herb growers would not be able to use pesticides unless permits were obtained specifically authorising the uses. This project was established to obtain minor use permits for the use of the following products on herbs: Pirimor (pirimicarb), Bugmaster (carbaryl), Ambush (permethrin), Ridomil Gold (metalaxyl + mancozeb) and Select (clethodim).
Research	Residue trials were conducted on coriander, dill, garlic chives, sorrel and thyme. The trials were established on schedule and treatments were applied. Residue samples were despatched to the analytical laboratory. The detailed protocols and results of the field experiments and laboratory analyses are provided in the appendix. The analytical laboratory experienced great difficulty in analysing the samples, because of the high concentration of essential oils in the plants. This problem delayed the delivery of analytical results for several months until a suitable methodology was developed. The results of the trials were incorporated into applications for permits that were despatched to the NRA 0n 20/6/2002.
Outcomes	One Permit Per5675 for Select has been cleared by the NRA. The others are pending. RIRDC and the herb growers will be notified when they are issued.
Implications	When issued, the permits will enable the herb growers to legally use the products to improve their crop protection programs against insects and weeds.
Publications	None

Project title:	Nutritional requirements of coffee trees in northern New South Wales
RIRDC Project No.:	CPE-1A
Researcher:	Mr. John Zentveld
Organisation:	CAPE Australia 179 Broken Head Road NEWRYBAR NSW 2479
Phone:	(02) 6687 1004
Fax:	(02) 6687 1335
Email:	cape@zentvelds.com.au
Objectives	· To establish optimal nutritional requirements of Arabica coffee grown under sub-tropical conditions in northern New South Wales for sustainable yields of high quality coffee using N.P.K fertilisers together with leaf and soil analysis.
Background	The coffee industry in northern New South Wales is a relatively new industry. Established by farmers seeking to diversify or redirect their crop base in the early 1990s, it was discovered that little was known about the nutritional requirements of the coffee trees. Consequently RIRDC was approached with the view that they fund research into the nutritional requirements of Arabica coffee trees for the embryonic coffee industry. It was felt that this research would assist existing coffee farmers in maximising crop yields. It was felt also the scientific research would serve to encourage new growers to enter into the industry therefore increasing the possibility of creating a future export commodity as well as assisting in satisfying the growing Australian demand for gourmet coffee.
Research	In essence, four different fertiliser combinations (consisting of different combinations of phosphorus, nitrogen and potassium) were applied to newly planted coffee trees. The height of these trees was measured throughout the study period to provide an indication of tree growth in response to the differing fertiliser combinations.
Outcomes	Analysing the tree growth during the period it was found that there was little or no difference in tree height between the four different treatments irrespective of the differing nutrient treatments.
Implications	It is possible that the application of phosphorous by hand in solid particle form throughout the trial block may have reduced actual uptake rates by the coffee trees in dry weather. Coffee tree growth increased dramatically between the months of September 2001 and March 2002. This closely coincided with the introduction of fertigation equipment on the farm, whereby nutrients applied to the trial (excluding phosphorus) were done so via fertigation. However, as only one growth measurement of the coffee trees was taken following the introduction of the fertigation equipment, there is no direct evidence for such a relationship. Therefore such a conclusion that fertigation increases the growth of coffee trees is purely speculative. As such, more research needs to be undertaken in this area to determine if a relationship exists.
Publications	Nutritional requirements of coffee trees in northern New South Wales, RIRDC Research Report No. 02/102 (in press)

Project title:	THE OLIVE PRESS - Australian Olive Association Magazine
RIRDC Project No.:	AOL-3A
Researcher:	Mr John Egan
Organisation:	Australian Olive Association PO Box 309 PENDLE HILL NSW 2145
Phone:	(02) 9863 8735
Fax:	(02) 9636 4971
Email:	secretariat@australianolives.com.au
Internet:	www.australianolives.com.au
Objectives	· The Olive Press is to be the principal communications forum for the olive industry, and as such to have a significant and positive impact on the development potential of the infant Australian olive industry and ultimately on its success as a significant import replacement and exporting industry.
Background	In 1998 the Australian Olive Association Board recognised the need for a quality industry specific magazine to serve the needs of a new emerging industry. The project was to develop the Association’s existing newsletter into a professionally produced and independently edited magazine covering all aspects of the olive industry. However, financing the project at that stage of the Association’s and the industry’s development was not possible. RIRDC provided financial support over three years for the production of The Olive Press, the official journal of the Australian Olive Association.
Research	The Olive Press is the primary vehicle for disseminating research and technical reports and articles direct to all stakeholders in the Australian olive industry and complementary copies are sent to various individuals and institutions overseas.
Outcomes	The magazine disseminates all forms of industry information – research and technical; industry developments, issues and news; new products and technology; book reviews; health issues; letters to the editor; and nationwide industry specific advertising. The magazine continues to grow with each issue and consolidate its position as the premier publication supporting the sustainable growth and development of the emerging Australian olive industry.
Implications	The primary implication of The Olive Press is that it has provided all participants in the olive industry with a reliable and objective source of information and provided a forum for open debate of pertinent industry issues. The publication has also served to enhance the image and credibility within the industry of its peak body, The Australian Olive Association.
Publications	The Olive Press is produced quarterly - Summer, Autumn, Winter and Spring issues. The first issue was the Summer 1998 (December).

Project title:	Increasing the export potential-opportunities for Australian garlic
RIRDC Project No.:	DAV-163A
Researcher:	Gisele Irvine and Samantha Sterling
Organisation:	Department of Natural Resources & Environment (Vic) Institute for Horticultural Development Private Bag 15 SCORESBY BUSINESS CENTRE, VICTORIA 3176
Phone:	(03) 9210 9222
Fax:	(03) 9800 3521
Email:	Gisele.Irvine@nre.vic.gov.au, Sam.Sterling@nre.vic.gov.au
Objectives	· To provide information on the yield benefits and pharmaceutical quality of virus-tested garlic to allow the Australian garlic industry to access new market opportunities and increase productivity to meet the demands of those markets.
Background	Currently, the garlic industry in Australia is small (350 tonnes per annum in the three years prior to 1995) and targeted primarily at the domestic (fresh) market. Imports are significant, totalling 2,500 tonnes in 1996 and often cheaper than the local product (coming from China, the USA and Argentina). These imported products flood the market reducing prices. The Australian Garlic Industry Association (AGIA) has collaborated with IHD, Knoxfield on two prior RIRDC-funded programs: BIO-1A, aimed at increasing productivity by reducing yield losses from virus (development of virus-tested seed stock), and DAV-124A, aimed at identifying new market opportunities for Australian garlic as a pharmaceutical product based on the level of bioactive compounds (alliin) within the bulb. The success of these programs led to a rapid expansion in the Australian garlic industry (1200 tonnes expected harvest in 1998, from 130 hectares). Further expansion of the industry is dependent on the availability of the virus-tested seed stock and markets available for the pharmaceutical grade product. The AGIA, in conjunction with commercial interests, sought evaluation of the virus-tested seed stock, both with respect to its alliin levels (pharmaceutical quality) and purported yield increases. Clear definition of the potential benefits were considered essential to enable industry to exploit new international markets based on pharmaceutical interests.
Research	Field trials were conducted at the Sunraysia Horticultural Centre as a central region for Victorian, South Australian and NSW interest's over a period of two years. Virus-tested and commercial garlic was grown under aphid-proof screenhouses and also under commercial conditions to evaluate yield differences, re-infection rates and alliin levels. Alliin levels were investigated for all the cultivars and under all the field trial conditions. Viruses known to affect garlic yields are Onion Yellow Dwarf Virus (OYDV), Leek Yellow Stripe Virus (LYSV) and Shallot Latent Virus (SLV), when in combination with either or both of the former two viruses.
Outcomes	The outcomes of this project have been the evaluation of the virus-tested garlic cultivars. Some of these cultivars gave consistently higher yields than the industry standards, under two very different climatic seasons. The study indicated that infection of garlic by yield reducing viruses does occur in the first year of commercial planting given a source of virus and winged aphid colonies. The alliin level of the virus-tested garlic was found to be not significantly higher than the industry standard material, but the yield increases of some virus-tested cultivars allow a greater amount of alliin to be produced per hectare.
Implications	This project has indicated that higher yields can be gained by planting particular virus-tested garlic cultivars and that higher yields can be seen as being economically attractive in the commercial production of alliin given reliable markets and adequate monetary returns from these markets.
Publications	Irvine and Sterling, 1999,2000,2001 Australian Garlic Industry Association Seminar Proceedings. Increasing the export potential-opportunities for Australian garlic, RIRDC Research Report No. 02/096, 26 pgs, 2002

Project title:	Commercial viability of Senna tora gum production in Australia
RIRDC Project No.:	UCQ-15A
Researcher:	Kerry Walsh and David Cunningham
Organisation:	Plant Sciences Group School of Biological and Environmental Sciences Central Queensland University ROCKHAMPTON QLD 4702
Phone:	Kerry Walsh (07) 4930 9707
Fax:	Kerry Walsh (07) 4930 6536
Email:	k.walsh@cqu.edu.au, davidcunningham@ozemail.com.au
Internet:	science.cqu.edu.au/psg
Objectives	· Assess potential for food gum production from Senna tora · Source and multiply seed of known provenance · Use yield data in economic analysis · Recommend on feasibility of production.
Background	Seed gums are classed as a "thickener/vegetable gum" in foods and are also used in a range of non-food applications including textile and paper manufacturing. The main sources of seeds gums on the world market are carob (locust bean) and guar, an increasingly important gum is sourced from Senna tora and Senna obtusifolia in India. Australia currently imports all of its seed gum requirements. S. tora and S. obtusifolia are established in Australia as weeds, infesting approximately 600,000 ha in coastal north and far north Queensland. The patent for the use of S. tora/obtusifolia gum in conjunction with carrageenan, the main use of the product in canned pet foods, will expire in September 2003. As the patent expires, industry users will encourage production in areas other than India to diversify supply options. It is therefore strategic to consider the potential for production of this gum in Australia at this time.
Research	· Literature review on the potential for production of Senna tora · Senna tora seed location and sourcing · Field and glasshouse trials to multiply seed and estimate yields · Assessment of economic feasibility of cropping Senna tora in Australia.
Outcomes	· Literature review on the potential for production of Senna tora · Senna tora seed was sourced within Australia and multiplied in glasshouse trials · Glasshouse and field yield estimates were low, too low to support a viable industry on a return of $250/tonne seed in the economic model used. However, higher yields are reported overseas and should be possible here, given attention to agronomy and cultivars.
Implications	Given attention to agronomy and cultivars, a commercial industry could be established in Australia. A growers group could negotiate with pet food industry users regarding contract pricing. However, establishment of an industry in Queensland would require legislation change with respect to the weed status of these species. Sourcing seed stock from all international distributions to establish a breeding program is advised.
Publications	Cunningham DC, Walsh KBW (2001) ‘Viability of Senna tora gum production in Australia.’ RIRDC Research Report No. 01/131, 34 pgs, 2001. Cunningham D (2001) Seed gums in Australian food processing. Food Australia 53, 209-212. Cunningham DC (2000) Commercial viability of Senna tora galactomannan production under Australian conditions. In ‘Autecology of Cassia brewsteri with respect to galactomannan production’, pp. 223-263. PhD Thesis, Central Queensland University, Rockhampton.

Project title:	A new rural industry – Stevia – to replace imported chemical sweeteners
RIRDC Project No.:	UCQ-16A
Researcher:	Prof. David Midmore Mr. Andrew Rank
Organisation:	Central Queensland University Plant Sciences Group Bruce Highway NORTH ROCKHAMPTON QLD 4702
Phone:	(07) 4930 9770 (07) 4930 6870
Fax:	(07) 4930 9255 (07) 4930 9255
Email:	d.midmore@cqu.edu.au a.rank@bigpond.com.au
Internet:	http://www.ahs.cqu.edu.au/info/science/psg/
Objectives	· To review overseas literature on Stevia and visit industry representatives in China and Japan to determine the relevance of information for potential establishment of a Stevia industry in Australia. · To bring stakeholders in a potential Stevia industry together to review findings and determine whether to proceed with further R & D.
Background	As a natural sweetener, commercial production of Stevia in Australia could lead to a reduction in the import of c. $12.0 million as artificial sweeteners. It could contribute to the well-being of diabetics, and others wishing to reduce sugar intake.
Research Outcomes	Visits to Japan and China were conducted and after presentation of information collected, and that from the literature review, to parties interested in Stevia, it was decided to proceed with further R & D on two parallel fronts. One, to establish and address the requirements for ANZFA approval of steviosides for use in the food industry, and the other to develop cost-effective production and processing protocols for a successful Australian industry. Should either of these show no reasonable progress within one year of a new RIRDC/University/stakeholder project, then further activities will cease. The support of all potential stakeholders (including the Health Industry) will be canvassed.
Implications	If successful, the further R & D will lay the foundation of an industry providing a nature sweetener to the predicted 1 in 4 Australians who will develop diabetes over their lifetime. It will also contribute to the general well-being and weight consciousness of many Australians.
Publications	--

Project title:	Enhancing fruit yield and quality of rambutan and longan by optimising irrigation and nutrition systems
RIRDC Project No.:	DAQ-251A
Researcher:	Yan Diczbalis
Organisation:	Department of Primary Industries Queensland Horticulture Institute PO Box 20 SOUTH JOHNSTONE QLD 4859
Phone:	(07) 4064 1130
Fax:	(07) 4064 2249
Email:	Yan.Diczbalis@dpi.qld.gov.au
Objectives	· The project aims were to monitor changes in longan and rambutan leaf and soil nutrient status over three seasons, measure grower fertiliser inputs in relation to the above, assess the effect of nutrient status on productivity, monitor tree phenology in relation to climate and irrigation management and quantify longan water/irrigation requirements.
Background	The Australian longan and rambutan industries, together with DPI, NT DPIF and RIRDC and other bodies have, over the last few years engaged in detail assessments of industry research and development needs. Industry strategic plans have been developed for the longan industry (Anon 1998) and a commitment to support research has been made by the relevant organizations. The longan and rambutan industries had identified nutrition and irrigation research as a priority issue.
Research	The project was unable to identify any direct links between tree nutritional status, fertiliser inputs and yield. Its important to note that all commercial orchards surveyed had relatively high leaf nutrient status and no unfertilised trees were included in the study. This suggests that within the range of nutrient status observed other factors such as pruning practices and climate play a more important role in flowering and subsequent yield. Despite the lack of relationship between nutrient status and yield, the survey of longan orchards indicated that high leaf N levels (N ³ 1.9%) during the period leading up to flowering should be avoided because it may be detrimental to flowering and hence subsequent cropping. Tentative leaf and soil standards were developed to use as a guide to fertiliser management.
Outcomes	A guide to fertiliser requirements was developed using a nutrient budget approach where nutrient inputs are based on fruit production and removal and take into account additional nutrient loss via leaching, runoff and fixation.
Implications	As a result of the development of a nutrient budget, inputs can now be geared to production rather then based on an ad-hoc approach. This allows for potential savings on fertiliser inputs, however, more importantly the nutrient budget approach has the potential to reduce fertiliser loss and hence contamination of sub-soils and drainage systems.
Publications	Nil publications. Presentations made to industry.

Project title:	Nutrition and irrigation management of rambutan for maximisation of yield and quality - Northern Territory
RIRDC Project No.:	DNT-26A
Researcher:	Chris Wicks
Organisation:	Northern Territory Department of Business, Industry and Resource Development Horticulture Division Berrimah Agricultural Research Centre GPO Box 3000 DARWIN NT 0801
Phone:	(08) 8999 2309
Fax:	(08) 8999 2049
Email:	chris.wicks@nt.gov.au
Objectives	· The project will improve our understanding of nutrient and irrigation management in rambutan, with particular emphasis on management through the fruit filling stage. This will lead to improved yield and fruit quality with more efficient use of fertiliser and irrigation inputs and hence increased profitability. The monitoring and reporting components of the project are closely linked with industry participation hence the uptake of new findings will be rapid and lead to improvements in productivity.
Background	The research program intends to monitor fertiliser and irrigation inputs, with particular emphasis during fruit development. The performance of orchards where regular "fertigation" is practiced will be compared to those where fertiliser is applied conventionally. The irrigation monitoring component will be used as an extension tool to develop increased awareness of the benefits of irrigation scheduling and to introduce growers to a range of soil moisture monitoring devices. The project will run in conjunction with the NT Rambutan Growers Group, a subgroup of the NT Horticultural Association.
Research	A new set of critical ranges has been developed for rambutan leaf and soil nutrition in the NT. These ranges were developed using a process called DRIS analysis in conjunction with statistical analysis of 13 sets of samples gathered from each of 15 different properties over a 36 month period. This nutrition data was also used to look for any differences between trees that had fertiliser applied by fertigation or by broadcast. While there were significant differences in both soil and leaf nutrient levels, there was no clear distinction between fertiliser systems. An attempt to link nutrient inputs to productivity was unsuccessful due to climatic influences severely restricting yields during the project. The analysis of water inputs showed that some properties had irrigation levels that were significantly different from the recommended levels. A great amount of workshopping and one-to-one information sessions were held.
Outcomes	A new set of critical ranges has been developed for rambutan leaf and soil nutrition in the NT. The decision making process for using fertigation or broadcast to fertilise rambutan has become clearer with there being no clear nutritional benefit or detriment and so any decision can be made on economic or management grounds. The ongoing analysis of irrigation inputs and soil water convinced 7 growers to begin using soil water monitoring equipment themselves.
Implications	The improved nutrition standards and the increased uptake by growers of soil water monitoring equipment should see an improvement in tree productivity and a decrease in inputs. Thus improving profitability. However the severe influence of climate seen over during the project suggests quite strongly that further work be carried out in the NT on the influence on environment on flowering and fruit retention.
Publications	Durian Germplasm Evaluation for Tropical Australia, RIRDC Research Report No. 02/106 (in press)

Project title:	Durian germplasm evaluation for tropical Australia phase 1
RIRDC Project No.:	ZTR-1A
Researcher:	Mr. Guiseppe Zappala
Organisation:	Zappala Tropicals Pty. Ltd. CMB. No 61 Deeral, via CAIRNS QLD 4871
Phone:	(07) 4067 5266
Fax:	(07) 4067 5315
Email:	zappala@iig.com.au
Objectives	· The introduction of the best durian clones of Asia from guaranteed budwood sources. · Propagation of these clones (single and multi-rootstocked) with the best nursery practices. · Development of an industry strategic plan · To compare growth rates and performances under different clonal tolerances to pests, diseases and strong winds. · To identify clones best suited for Phase 2 (Yield and Fruit Quality Assessment) for future Australian planting and export potential.
Background	Durian (Durio zibethinus Murray) is indigenous to the hot equatorial rainforest of Malaysia and Indonesia. Australia currently imports up to 500 tonnes of frozen durian. Australian fresh durian is popular in our domestic markets and the export potential is good. Our industry must be based on clones that produce quality fruit under local climatic conditions. This five-year project evaluated the responses of 30 newly imported Asian durian clones to the north Queensland tropical climate.
Research	During the clonal evaluation period, project trees were exposed to extreme weather patterns with regular cyclones, annual rainfall in excess of 6000mm and cold temperatures as low as 5°C. Clonal survival observations from these climatic conditions, combined with six rounds of tree measurements and early flowering and fruit yield data, were used to select the top seven new clones.
Outcomes	Hepe, D. macrantha, D 175 (Red Prawn), DPI Mon Thong, Hawaiian Mon Thong, D 190 and Kradum Thong are the seven new clones highly recommended. Two clones on the current recommended Australian planting list, Kan Yao and Australian Luang were included as "standards" for comparison purposes. The Hawaiian Mon Thong No 315 performed well with an estimated fruit yield of 140 kg from this 10-year-old tree.
Implications	The new clones Hepe, D. macrantha, D 175 (Red Prawn), DPI Mon Thong, Hawaiian Mon Thong, D 190 and Kradum Thong will provide a 175% increase to Australia’s current recommended planting list. These additional planting choices provide growers with the confidence required to move forward for industry expansion in tropical Australia and will ensure that our high value horticultural industry contributes to the Australian economy.
Publications	Zappala, G., Zappala, A. J., and Diczbalis, Y. 2002 "Durian Germplasm Evaluation for Tropical Australia. Phase 1." RIRDC Research Report No. 02/091, Rural Industries Research and Development Corporation, Canberra, February 2002 p147. Zappala, A. J. "Australian Durian Industry Strategic Plan." 2001-2006. RIRDC Web Publication W02/016, Rural Industries Research and Development Corporation, Canberra, February 2002.

Project title:	*Acacia saligna as a fodder source for ruminants*
RIRDC Project No.:	CUT-6A
Researcher:	Dr Gaye Krebs
Organisation:	Curtin University of Technology Muresk Institute of Agriculture NORTHAM WA 6401
Phone:	(08) 9690 1523
Fax:	(08) 9690 1500
Email:	g.krebs@curtin.edu.au
Objectives	· To determine the usefulness of Acacia saligna as an environmentally sustainable addition to the grazing system. In the first instance this involves determining the nutritive value of A. saligna as a fodder source for ruminants.
Background	Land degradation is an issue of major concern in Australia. Overgrazing can be caused by continuous overstocking, but may also result from short-term overstocking that occurs in many areas which experience a feed shortage/deficit during the summer/autumn period. A saligna represents a fodder source which potentially may be utilised during the summer/autumn feed deficit period. The common conclusion drawn by researchers regarding the value of A. saligna is that it is inadequate as the ruminant’s sole source of nutrients. This is largely attributed to its condensed tannin content. Environmental factors also affect the nutritive value of various browse species, and thus there was a need to determine the nutritive value of A. saligna grown in the Mediterranean climate of Western Australia.
Research	Three pen trials, together with a laboratory-base trial, were conducted to evaluate the usefulness of A. saligna as a source of feed for ruminants. The feeding trials involved providing sheep (or goats) with A. saligna as either the sole or supplemental source of nutrients and measuring animal production responses (feed intake, wool growth, etc) and metabolic responses (nitrogen balance, rumen pH, dry matter and organic matter digestiblity). The laboratory-based trial involved determining the effects of maturity and season on the nutritive value of A. saligna.
Outcomes	Many factors affect the nutritive value of A. saligna and as a consequence the nutritive value of this material is highly variable. At times it is far from acceptable as a feed source, at other times it can meet the maintenance (feed) requirements of both sheep and goats (goats do not have superior ability than sheep in utilising A. saligna as a source of nutrients). Results indicate that generally as the plant matures, its nutritive value declines, however, this season in which the A. saligna is lopped (initially grazed) appears to confound this effect. Regrowth from spring lopped A. saligna generally has a higher nutritive value than regrowth from autumn or winter lopped trees, although this difference becomes much less pronounced as the plant matures.
Implications	The research has indicated that under certain circumstances/conditions A. saligna would be a useful addition to a potentially environmentally sustainable grazing system. However, there is a need to investigate the circumstances that predispose A. saligna to becoming a high-tannin feed, subsequently lowering its feed value.
Publications	Howard, D., Krebs, G.L. & van Houtert, M (in press) The value of Acacia saligna as source of feed for sheep. Proceedings of the Acacia Symposium, held at Dalwallinu, WA, 13-14 July 2001 (refereed proceedings). Accepted: Krebs, G.L. and May, D. The effect of season and age of regrowth on the nutritive value of A. saligna (Rangelands Conference, Kalgoorlie, Sept 2002) Howard, D.M. (2002) The Value of Acacia saligna as a Source of Fodder for Ruminants, Masters Thesis, Curtin University of Technology May, D. (2001) The Effect of Age of Regrowth and the Season of Cutting on the Nutritive Value of Acacia saligna, Honours Dissertation, Curtin University of Technology.

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