The response of maize - pigeonpea Intercrop to nitrogen and phosphate Fertilizers

Abstract

Two experiments were conducted during the short rainy season of October 1989 to April 1990to study the effect of nitrogen and phosphate fertilizer application on the intercrops of maize and pigeon pea on their growth, yield and yield components. One experiment was sited at the Field Station of Faculty of Agriculture, Kabete and the other at Machakos Farmers Training Centre, Machakos. Maize (zea mays L.Katumani Composite B) was intercropped with pigeonpea (Cajanus cajan) in alternating rows and nitrogen and phosphate fertilizers applied at 0, 20, 40 and 60 kg N or P/ha each as calcium ammonium nitrate (CAN) and triple super phosphate (TSP) respectively. Half of nitrogen was applied at planting and the remaining half topdressed. The effects of all combinations of the fertilizer rates on the growth, yield and yield components of the intercrops were studied. The treatments were replicated three times. The results showed that application of nitrogen fertilizer did not have any significant effects on the pigeonpea component under the intercropping system at both sites. On maize, however, nitrogen showed significant increasing effect on yield at Machakos while it had non-significant effects at Kabete. It also showed significant effects on the number of kernels per row at Machakos and not at Kabete. Nitrogen had no significant effect on all other parameters monitored. Phosphorus increased shoot dry 'weight of maize significantly at Machakos but showed no significant effect at Kabete. All other remaining parameters studied did not show any significant effect on all the monitored parameters of pigeon pea at both locations. These observations led to the conclusion that when applying fertilizers under intercropping systems, nitrogen should be applied to cereal component only while phosphate should be applied to both crops.