Mineral Nitrogen Fertilizer and Compost Effects on Wheat and Maize Yields in Crop Sequences Including Intercropped Legumes

摘要

THE EXPERIMENT was conducted at Mallawi Agric. Res. Stn. (Middle Egypt) during three years (2010/2011-2012/2013) to study mineral N fertilizer and compost effect on wheat and their residual effect on maize (second crop) in crop sequence. The experimental design was a split plot in a randomized complete blocks arrangement with three replications. The main plots were devoted to the three fertilizer treatments of wheat (100% mineral N fertilizer, 50% compost + 50% mineral N fertilizer and 25% compost +75% mineral N fertilizer)-9, while the sub plots were allocated to the three crop sequences, i.e. wheat/maize (Bi), wheat + faba bean/maize + cowpea/ fahl berseem (B2) and wheat + fahl berseem/maize+soybean (B3). The results showed that the grain yieldsof wheat and maize in the two fertilizer treatments that included compost were higher than the treatment receiving 100% mineral N. The crop sequence (wheat + fahl berseem/maize + soybean (B3)) produced the maximum value of weight of kernels/spike, weightof 1000 kernels and grain yield/fed of wheat. The crop sequence (wheat-*- faba bean/maize + cowpea/clover (B2)) produced the maximum values of weight of 100 kernels and grain yield of maize. The yield and yield components of wheat or maize to which mineral N and compost were applied were lower in the first year than those obtained with 100% mineral N, while in the second and third years the values were higher. The yield and yield components of wheat or maize were higher in the third year than in secondyear and also those in the second year was higher than in the first year. The crop sequence (B2) and the application of mineral N combined with compost at both rates (A_2 & A_3) had the highest values soil available N,P,K and organic matter (OM) with values before planting. The results also show that growing wheat and maize in crop sequence with inclusion of legume intercrops (B_2 and B3) and fertilizing with mineral N fertilizer combined with compost (A_2 or A_3) produced the highest values of intensification index and net return.