Factors affecting the regrowth of Pennisetum americanum under frequent defoliation

Abstract

Data on the regrowth of pearl millet under a 3-weekly defoliation regime, taken from an experiment at Camden, N.S.W., which involved two cultivars, two planting dates and three cutting heights, were examined in an attempt to determine factors influencing the rate of recovery from defoliation.

Over all treatments, there was a positive (P < 0.01) association between regrowth over 3 weeks and the leaf area index of the stubble at the start of the regrowth period, and negative (P < 0 01) associations of regrowth with plant age and with the number of axillary branches. There was no association between regrowth and the total number of live tillers. This may have been due to the presence of decapitated tillers In the count. For late-planted crops, there was a positive (P < 0.01) association between regrowth and temperature.