Evaluation of high densities of some corn verities on soybean productivity.

The present study was carried out to evaluate the effects of high plant densities of three corn varieties on soybean productivity and land equivalent ratio (LER) under two intercropping systems. Three corn varieties S.C. 128, S.C. 130 and Syn. Cairo 1 with soybean variety Giza 111 were tested under intercropping and solid plantings. Intercropping systems adopted were alternating 2:2 ridge (70 cm/ridge) and mixed one (140cm/bed). Soybean plants were grown in two rows per ridge and beds and thinned to two plants at 15 and 20 cm between hills under intercropping and solid plantings, respectively. Corn plants were thinned to two plants per hill distanced at 20, 25 and 30 cm between hills under intercropping and solid plantings. A split plot distribution in randomized complete block design with three replications was used. Corn varieties were randomly assigned to main plots, whereas, cropping systems were distributed in the sub-plots and corn plant densities were assigned to sub sub-plot. Results showed that soybean with corn variety S.C. 130 gave the highest seed yield. Alternating ridges 2:2 system produced higher yield than mixed one. Increasing distance between corn hills from 20 to 30 cm increased yield of intercrops. Alternating ridges 2:2 gave higher productivity and land usage by intercropping soybean with corn varieties of Syn. Cairo 1 and S.C. 130, distanced 30 cm between hills in case of increasing number of corn plants per unit area from 50 to 100% of recommended solid culture.