Response of Short Duration Castorbean to N, P and K Fertilizer

Abstract

Field experiment were set up during 1990-1992 in sandy loam and red clay soil in farmer's field in Khon Kaen and Loburi provinces, respectively. The treatments were arranged in split plot design with 3 replicated. Main plot consisted of 3 short duration castorbean varieties : Ubol. 90, H. 22 and Khumpu in 1990, Ubol. 90, IAC.38-4 and 7811-16 in 1991 and Ubol. 90, CH-17 and IAC. 38-4 in 1992. Sub plots consisted of 4 rates of chemical fertilizers: 0-0-0, 5-5-5, 10-10-10, and 15-15-15 kg/rai of N-P2O5-K2O. Result showed that fertilizer application highly and significantly increased castorbean seed weight. Apparently, marked yield response was observed at the rate of 10-10-10 to 15-15-15 kg N-P2O5-K2O/rai. Poor yield was observed in Khumpu variety whereas data from Ubol. 90, CH-17, IAC. 38-4, 7811-16 and H.22 showed high seed weight.