Effects of N，P，K and their combinations on yield and benefit of hybrid Pennisetum purpureum cv. Guimu No.1 grown in field bund

The demands and optimum proportion of N, P and K of hybrid Pennisetum purpureum cv. Guimu No.1 grown in field bund were studied with 3414 design. The results showed that its response to formula fertilizing was good. Among the treatments, the best one is N2 P2 K2 (N 414 kg/hm2, P2O5 138 kg/hm2, K2O 276 kg/hm2) and its yield was the highest (256.811.18） t/hm2, and the difference with the low level treatments was significant (P0.01). The yield was increased by 16.6% compared with the check. Based on the analysis of the effect prediction model, the estimated highest yield was 259 t/hm2 and the relevant fertilizing formula was 414 to N 621 kg/hm2, P2O5 140 kg/hm2 and K2O 204 kg/hm2. The best economic formula wasN 414 kg/hm2, P2O5 140 kg/hm2 and K2O 172 kg/hm2, and the relevant yield was 256 t/hm2.