Effect of date of sowing and rainfall on sustainability of yield and rainwater use efficiency in cereal crops under arid alfisols

摘要

An assessment of the effects of date of sowing and crop seasonal rainfall on the sustainability of yield and rainwater use efficiency (RWUE) of sorghum, pearl millet and foxtail millet sown on five dates at 15 days interval from first fortnight of June to first fortnight of August during 2009 to 2014 under arid Alfisols at Anantapur has been made in this paper. A suitable date of sowing has been identified for each crop based on the relationships sorghum equivalent yield with crop seasonal rainfall and crop growing period observed in the 6-year study. The yield was significantly influenced by the variation in the crop seasonal rainfall and crop growing period when sown on different dates of sowing. It was significantly higher when crops were sown with the onset of monsoon in the first fortnight of June, and decreased with the subsequent sowings. Among crops, sorghum attained maximum mean yield of 923 kg ha(-1) with RWUE of 2.73 kg ha(-1) mm(-1); while pearl millet attained mean yield of 873 kg ha(-1) with RWUE of 2.95 kg ha(-1) mm(-1) and foxtail millet attained mean yield of 646 kg ha(-1) with RWUE of 1.64 kg ha(-1) mm(-1) when sown during first fortnight of June. Based on the ranks assigned to the yield attained on different dates of sowing in different years, pearl millet was superior for sustaining maximum yield and RWUE compared to sorghum and foxtail millet under arid Alfisols at Anantapur.