Agriculture Agriculture, Multidisciplinary Life Sciences & Biomedicine Science & Technology
Context. The legume shrub/tree leucaena (Leucaena leucocephala (Lam.) de Wit.) is highly regarded as a cattle fodder, although it is considered an environmental weed in many parts of Australia. Aims. We investigated the feasibility of developing a forage variety of triploid leucaena through interspecific hybridisation that is sterile (without seeds) as a strategy to mitigate its weed risk. Methods. A conventional breeding strategy was used to create triploid hybrids from hand crosses between tetraploid and diploid species of leucaena. Molecular markers were developed to confirm successful crosses and flow cytometry was used to confirm the ploidy level. The plants are being evaluated for flowering behaviour, seed and herbage production across two environmentally diverse sites at Carnarvon and Kununurra in northern Western Australia. Key results. During 2018/19 and 2019/20, 2260 crosses between 45 different combinations of diploid females by tetraploid males and their reciprocals have created over 3000 putative triploid hybrid plants. This is the first time that triploids have successfully been created in Australia and 10 new parental combinations were created as a world -first. Conclusions. A cohort of sterile triploid plants has been identified and selections will be made based on their edible biomass productivity, insect tolerance, capacity for regrowth after cutting, nutritive value and plant chemistry (including anti-methanogenic responses). A sterile leucaena variety will have application not only in Australian grazing systems but also in other tropical regions of the world. Implications. A cost-effective technology for mass vegetative propagation of leucaena will be required for commercialisation of a sterile variety.
Details
Title
Successful creation of seedless (sterile) leucaena germplasm developed from interspecific hybridisation for use as forage
Authors/Creators
D. Real - Department of Primary Industries and Regional Development
C. Revell - The University of Western Australia
Y. Han - Department of Primary Industries and Regional Development
C. Li - Murdoch University, Centre for Crop and Food Innovation
M. Castello - Dept Primary Ind & Reg Dev, South Perth, WA 6151, Australia
C. D. Bailey - New Mexico State Univ, Dept Biol, Las Cruces, NM 88003 USA
Publication Details
Crop and pasture science, Vol.74(8)
Publisher
Csiro Publishing
Number of pages
14
Grant note
Department of Primary Industries and Regional Development, WA, Australia
P.PSH.0884 / Meat & Livestock Australia Donor Company