Idluence of weather and soil moisture regimes on winter groundnut (Arachis hypogaea) productivity

Abstract

Received: January 2001 An experiment was conducted during 1994 96 to identify an ideal time for sowing winter groundnut (Arachis hypogaea L.) to match the available water supply without subjecting the crop to terminal soil moisture stress. High relative humidity during morning with early sown crop (earlier than 31 December) significantly reduced the plant height. Total dry matter production was positively and significantly influenced by the minimum temperature (Tmi,) during pod filling phase (S,), while the yield attributes were negatively influenced by T,,, during S, phase. Dry matter production of crop sown in November and December, even with irrigation schedule of 1.0 IW : CPE ratio was lower than that of late sown crop irrigated at 0.8 and 0.6 IW : CPE ratio. Decrease in diurnal variation in temperature ( 17.g C) due to increase in minimum temperature ( 19.6OC) reduced the translocation of photosynthates into pods, leading to reduced the pod yield with January sowing. The sub optimal weather conditions during crop period with January sowings could not be mitigated by frequent irrigations (1.0 IW : CPE ratio), as such the ideal time for sowing winter groundnut was found to be 16 November to 16 December for Anantapur district of scarce rainfall zone in Andhra Pradesh.