Response of rainfed sorghum genotypes to nitrogen fertilization

摘要

The sorghum, a third important cereal crop in the country is a major dry land crop for its utility as food, feed and forage. Grain sorghum is currently grown over 11.89 m.ha in the country. Since the possibility of increasing land under sorghum cropis quite limited, the high yielding varieties hybrids and fertilizers are the answer to increase the sorghum productivity for sustained production. A field experiment was conducted at the Agricultural Research station Chas, Dist. Ahmednagar, Maharashtra, India) on medium black soil during rabi season of 1997 with a view to test the performance of different rainfed sorghum genotypes to nitrogen fertilization. The soil of the experiment was medium black with total N (113 kg ha~(-1)) available P (28.44 kgha~(-1)) and available K (786 kg ha~(-1)) with pH of 8.24 and EC 0.13 dSm~(-1). The treatments consisted of twelve combinations of three sorghum genotypes (CSH-15R, SPV-1155 and M 35-1) and four nitrogen levels (0, 30, 60 and 90 kg N ha~(-1)). The design of the experiment used was randomised block with three replications. Nitrogen was applied as per treatments at seeding by placement method. Besides, 40 kg P_2O_5 ha~(-1) was applied as basal dose for all treatments. The sorghum genotypes were sown on 2nd October 1997 and the harvesting of all genotypes was done on 10th February 1998. The rainfall (265 mm) received in the month of August and September was useful for recharging the soil profile. The total rainfall received during crop growth period was56 mm in 2 rainy days.