Residual Effects of Some Preceded Winter Field Crops on Productivity of Intercropped Soybean with Three Maize Cultivars

摘要

A two - year study was carried out at Sids Agricultural Experiments and Research Station, ARC, Beni - Sweif governorate, Egypt, during 2012/2013 and 2013/2014 to study the residual effects of the preceded berseem, sugar beet and wheat crops on yield and its attributes of intercropped soybean with three maize cultivars. The treatments consisted of three local maize cultivars (S.C.122, T.W.C.310 and Giza2) that grown with one local soybean cultivar Giza22 in alternating ridges 2:2 and three preceded winter crops (berseem, sugar beet and wheat). A split plot design with three replications was used. The results showed that the preceded berseem (the Egyptian clover) crop residues which had positive allelopathic effects on soil properties contributed mainly in productivity of intercropped soybean with maize. On the other hand, Giza 2 cultivar had a lower negative effect on intercropped soybean productivity than S.C. 122 or T.W.C. 310 cultivar. The interaction between the preceded winter crops and maize cultivars was significant for all the studied soybean traits except branches dry weight, numbers of branches and seeds/plant. Intercropping soybean with T.W.C. 310 cultivar that followed berseem produced 1.78 ton/ha of soybean seeds in addition to 5.60 ton/ha of maize grains. Yield advantage was achieved because of land equivalent ratio was exceeded 1.00. Dominance analysis proved that soybean is dominated component. The highest monetary advantage index was obtained by intercropping soybean with maize cultivar T.W.C. 310 that followed berseem.