Track 1-03: Development and Impact of Sown Temperate Species

Description

Although white clover (Trifolium repens) is the most widely used legume in grazed pastures of temperate and sub-tropical regions, it is severely restricted in genetic diversity for adaptive traits to low soil fertility and other stress environments, including drought. The objective of this research was to transfer traits for wider adaptation from other clover species by hybridisation. Eight Trifolium species with contrasting adaptations were shown by DNA sequence phylogenetics to be closely related to white clover. Interspecific hybridisation was undertaken among these species using embryo rescue, and an array of partially fertile F1 hybrids was obtained. Population development from these F1 hybrids showed that hybrids involving six taxa could be selected for high sexual fertility. Most showed strong inter-species chromosome pairing and the potential for introgression of exotic genomes into white clover. Several of the new genomic combinations, which do not occur in nature, will improve prospects for extending the adaptive range of white clover.

Share

COinS
 

Widening the Adaptation of White Clover by Incorporation of Valuable New Traits from Wild Clover Species

Although white clover (Trifolium repens) is the most widely used legume in grazed pastures of temperate and sub-tropical regions, it is severely restricted in genetic diversity for adaptive traits to low soil fertility and other stress environments, including drought. The objective of this research was to transfer traits for wider adaptation from other clover species by hybridisation. Eight Trifolium species with contrasting adaptations were shown by DNA sequence phylogenetics to be closely related to white clover. Interspecific hybridisation was undertaken among these species using embryo rescue, and an array of partially fertile F1 hybrids was obtained. Population development from these F1 hybrids showed that hybrids involving six taxa could be selected for high sexual fertility. Most showed strong inter-species chromosome pairing and the potential for introgression of exotic genomes into white clover. Several of the new genomic combinations, which do not occur in nature, will improve prospects for extending the adaptive range of white clover.