Colloque

Some Causes of Low Seed Yields in Red Clover

J. W. Boyes

Membre a labase

J. W. Boyes

Résumé du colloque

Plants of red clover (Trifolium pratense L.) vary greatly in the amount of seed that they produce. In diploid plants of the Dollard variety the best seed-yielding progeny plants seem to come most frequently from outcrosses between two high seed-yielding parents. Further studies have shown neither abnormal meiotic behaviour of chromosomes nor pollen abortion is strongly correlated with seed-yield in these plants. However, we now have evidence of three other causes of reduces seed yields; failure to produce embryo sacs, slow or limited pollen-tube growth, and the collapse of developing ovules. In tetraploid plants of this variety, meiotic irregularities account for only a part of the pollen abortion which, with other causes such as ovule abortion, contributes to reduction of seed yields.