New research uncovers huge potential of native legumes as pasture and grain crops
20 Oct 2011
Two new research reports released by the Rural Industries Research and Development Corporation suggest there is significant potential for native legumes to be developed as pastures or crops.
A major limitation to native legumes being grown on a commercial scale is the difficulty of harvesting their seeds. However, one of the key findings of the research on the promising pasture species Cullen australasicum was a breakthrough harvesting method that will allow this species to be harvested using commercial header equipment.
Native legumes have the benefit of being adapted to local environmental conditions and in the case of Cullen australasicum may be more drought tolerant than current exotic pasture legume cultivars.
The research, funded by RIRDC and carried out by the South Australian Research and Development Institute (SARDI), investigated ways to grow and harvest Cullen using a traditional harvester.
SARDI researcher, Eric Kobelt said Cullen australasicum is a drought hardy, deep rooted pasture plant that can be grazed by livestock and is suited to low to medium rainfall areas.
“Cullen is a resilient perennial pasture species, but its commercialisation has been hampered by problems with harvesting seed,” Mr Kobelt said.
“This research found that windrowing Cullen like canola within three weeks of the first seed pods being formed allowed yields of up to 700 kg/ha. Windrowing involves cutting the stems of the plants and leaving in long rows to dry. This retains the seed in the pod, rather than the seed pods shattering open, releasing the seed on the ground. The rows can then be harvested.
“These techniques will allow larger amounts of quality, cheaper Cullen seed to be available.”
The research project found that with the right management and environmental conditions Cullen australasicum could produce more seed than that produced by lucerne - around 500 kg/ha - in the same dryland conditions.
The study also found that best seed yields can be achieved when seed production is set up early in the season, which allowed uniform and reliable seed production. The report recommends more research into the natural diversity of Cullen populations to find plants with more uniform flowering and better seed retention.
Another RIRDC-funded native legume research project assessed the potential of native Australian legumes to be developed as grain crops for dry environments in the southern Australian grain belt. Researcher, Megan Ryan of the University of WA used a glasshouse study to show that the native legumes studied had similar oil, protein and fibre content in seed as domesticated exotic legume crops, and have the potential to be developed as commercial legume crops. A literature review showed that the species showing most promise were Glycine canescens, Cullen tenax, Swainsona canescens, S. colutoides, Trigonella suavissima, Kennedia prorepens, Glycyrrhiza acanthocarpa, Crotalaria cunninghamii and Rhynchosia minima.
The reports on this research, “Developing Harvest Technologies for Cullen australasicum” and “Native Legumes as a Grain Crop for Diversification in Australia” are available for free from the RIRDC website: www.rirdc.gov.au.