The influence of seed size and seeding rate on the growth of two strains of subterranean clover (Trifolium subterraneum L.)

Abstract

The results of a field experiment are presented in which large and small seeds of two strains of subterranean clover, Dwalganup and Mt. Barker, were sown at equal weights of viable seed per unit area. Two seeding rates were examined, and four harvests made during the winter-early spring period. The general conclusion is drawn that seed size has no effect on the growth rate of a subterranean clover sward, provided that sowing rate is held constant. It was found that the earlier strain Dwalganup outyielded the mid-season Mt. Barker strain in terms of total tops weight per unit area, although leaf production was higher in the mid-season strain. Root production, however, was consistently greater in Mt. Barker than in Dwalganup, and in fact total yields (of both tops and roots) were very slightly higher in the Mt. Barker strain. Growth rates are discussed in relation to net assimilation rates and leaf weights, and it is suggested that differences in root weight ratios between subterranean clover strains have not received adequate attention in the past.