Evaluation of white clover (Trifolium repens L.) commercial cultivars and experimental synthetics in south-west Victoria, Australia

A study was conducted to evaluate the relative performance of the cultivars, 'NuSiral' and 'Trophy', together with 13 other commercial cultivars and five experimental synthetics, under cattle grazing at Glenormiston, south-west Victoria, Australia. Analysis of the performance of the 20 white clover entries, based on clover content of swards, indicated significant (P < 0.05) differences among them. The, experimental synthetic GC 122, developed from elite lines evaluated in Australia, had a higher clover content than all the other entries in the trial. Cultivar 'Trophy' also had high clover content within seasons and across seasons and years. The clover contents of cultivars 'Mink' and 'NuSiral' was intermediate relative to the other entries. Cluster analysis of the cultivar-by-seasonal clover content data matrix generated four cultivar groups. While 'Emerald', 'Trophy', 'Tribute' and GC122 were members of group I, the high mean seasonal clover content group, 'Mink' and 'NuSiral' were in group III, the low mean seasonal clover content group. The four members of group I were developed from germplasm collected in dry environments, and bred in Australia. Using a combination of world sourced germplasm originating from dry environments, together with evaluation in dryland moisture stress environments, is a successful strategy for developing new white clover cultivars for Australia.