Combination effects of nitrogen,phosphorus and potassium on Pennisetum purpureum

Orthogonal design was used to determine the effects of combinations of N,P and K on plant height,tillers and DM yield in Pennisetum purpureum.Experimental data were analyzed by ANOVA and range analysis.The results showed that the best fertilizer combination was urea(900 kg/hm2)Ca-Mg-P(600 kg/hm2)+K2SO4(150 kg/hm2)and the effect sequence was NKP.The highest DM yield was 40.41 t/hm2 from 5 cuts per year.Significantly differences on plant height,single cut yield and total DM yield under different combinations were found at the 0.05 level,nor on tiller numbers.Regression analysis showed that there was significant correlation between plant height and single yield,but no significant difference was found between tiller numbers and DM yield(P0.05).