Effects of sowing date and nitrogen fertilization on growth, development and yield of a short day cultivar of millet (Pennisetum glaucum L.) in Mali

The effects of different nitrogen supplies on the performance of the short- day cultivar M9D3 of pearl millet (Pennisetum glaucum L. R.Br.) and their i nteraction with sowing time were analysed in a two-year experiment in Mall. The first sowing dates coincided with the beginning of the rainy season. T he second sowings were 20 days later. The sowing date affected only the eme rgence-earing duration independently of nitrogen application. The linear re duction in straw yield, caused by the shortening of the cycle, was not comb ined with a reduction in grain yield. The application of even low levels of nitrogen to millet crops always increased the grain yield, as a consequenc e of a higher number of productive panicles, while the straw production was positively affected only when the rainy season started early. The non-agre ement between the high productive potential of the first sowing crops and t heir grain yield, in comparison with the plants of the second sowing date, could be ascribed, first of all, to the more marked asynchrony between the time corresponding to LAImax and the grain filling phase, characterised by the maximum sink demand and, second, to a longer time interval during which stem growth and panicle growth are in direct competition. (C) 1999 Elsevie r Science B.V. All rights reserved.