Abstract:
A field experiment was conducted at Samaru farm of the Institute for Agricultural Research in 1990 and 1992 wet seasons with the objective of studying the effect of N and P on the yield and yield components of maize and rice under mixed cropping. Factorial combinations of four levels of N (0, 60,120 and 180kgN/ha) and three levels of P (0, 13.2 and 26.4kgP/ha) were laid out in a randomised complete block design with four replications. The results revealed that the grain yield of maize and rice were significantly influenced by N and P. In 1990, maize grain yield increased significantly upto 13.2kgP/ha at 0 and 60kgN/ha. There was no effect of P at 120 and 180kgN/ha. For rice, grain yield at 0 and 60kgN/ha was not influenced by P whereas, application of 26.4kgP/ha significantly increased grain yield at 120 and l80kgN/ha. In 1992 application of 13.2kgP/ha at each level of N significantly increased maize and rice grain yields. The highest grain yields were obtained at 120kgN/ha with 13.2kgP/ha suggesting that this fertilizer rate could be recommended for the mixture. Yield components of maize such as cobs per square metre increased significantly with levels of N and P but there were; no signifleant changes in shelling percentage and hundred grain weight of maize. The number of panicles per square metre, number of tillers per plant and number of filled grains por panicle were the yield components of rice that responded to Increased N and P. While threshing percentage and thousand grain weight were not affected. Other plant characters of both crops which were positively influenced by N and P were LAI, plant height and plant dry matter. There was highly significant and positive correlation between maize grain yield and yield component such as cobs per square metre (r = 0.586, r = 0.558) in 1990 and 1992 respectively. In rice however, grain yield was found to be significantly and positively associated with components of yield such as panicles per square metre (r= 0.915, r = 0.910) and number of tillers per plant (r = 0.851, r = O.850) in 1990 and 1992 respectively. Percent crude protein in plant leaves at maturity increased with the application of N alone but not with P. While percent P in leaves was significantly increased with both N and P. Percent N in the soil at Crop maturity increased significantly with N upto 180kgN/ha but was not affected by P. Similarly P content in soil was significantly and positively influenced by P but not with N application.
YIELD AND YIELD COMPONENTS OF MAIZE/RICE MIXTURE AS INFLUENCED BY NITROGEN AND PHOSPHORUS FERTILIZATION.
