COMPARISON OF YIELD COMPONENTS OF RED CLOVER AND ALFALFA

Yield components of five regrowth cycles, two in 1981 and three in 1982, of three red clover (Trifolium pratense L.) populations and three alfalfa (Medicago sativa L.) cultivars were compared in swards. Red clover left more stubble but produced less herbage and accumulated total yield (herbage, stubble and 10 cm depth root) at a slower rate than alfalfa during most regrowths. The percent leaf at flowering of red clover was similar to that of alfalfa. Maximum LAI declined during successive regrowths each year. Maximum crop growth rates were 30 and 34 g m −2 d −1 for red clover and alfalfa, respectively. Stem development (canopy height) followed patterns of accumulation of herbage yield. The initiation of stems was slower in red clover and stem populations were less than that of alfalfa. Selection for faster stem initiation rates, higher stem populations, and reduced partitioning of dry matter towards stem bases which would be left as stubble were suggested as ways of increasing the herbage yield of red clover.Key words: Trifolium pratense L., Medicago sativa L., yield components, growth analysis clover (red), alfalfa