Grasslands Trophy: a new white clover ('Trifolium repens L.') cultivar with tolerance of summer moisture stress

Abstract

A breeding project has developed a new synthetic white clover ('Trifolium repens L.') cultivar, Grasslands Trophy, that possesses tolerance of summer moisture stress in dryland pasture environments in the 850-1250 mm average annual rainfall temperate perennial pasture zone in eastern Australia. The breeding strategy used to develop Grasslands Trophy was an 'in situ' breeding cycle for: (i) identifying and selecting superior genotypes, (ii) crossing elite germplasm and (iii) progeny testing derived breeding lines for the expression of key agronomic and grazing value traits. The primary selection criteria were early vigour, herbage yield, persistence and seed yield potential. Parental selection was also applied for seed yield, uniformity of leaf size, uniform flowering pattern and freedom from disease and virus symptoms. Grasslands Trophy is medium-large in leaf size with stable leaf size, combines intermediate stolon density with intermediate stolon thickness, and expresses high stolon survival and strong autumn regrowth following summer moisture stress. Grasslands Trophy has mid-season flowering maturity, intensive flowering prolificacy and high seed yield capability. Agronomic results from trials in northern New South Wales and New Zealand indicate that Grasslands Trophy has broad adaptation, expresses high summer and winter growth activity, and is reliably persistent for at least 4 years.