Abstract:
Field experiment was conducted to investigate the effects of two cover crops, Mucuna pruriens var. cocchinchinensis and Canavalia ensiformis, on weed interference and yield of maize (Zea mays var Okomasa) in an intercropping system at different planting dates. The cover crops were intercropped 0, 2, 4 and 6 Weeks After Planting Maize (WAPM). The intercrop components were sown at 80x40 cm and arranged in a 1:1 spatial arrangement. Non-intercropped maize plots served as sole maize or control. Results showed that Mucuna had better spreading ability than Canavalia. The highest cover spread for Mucuna and Canavalia was observed when they were intercropped at 4 and 2 WAPM, respectively. Results also showed that the two cover crops exhibited (more than 56%) weed suppression when intercropped at 4 WAPM. The highest weed suppression for Mucuna and Canavalia were recorded when they were planted at 4 and 0 WAPM, respectively. The grain yield of maize increased with delay in planting both cover crops (i.e., from 0 to 6 WAPM). The highest grain yield values of 2.95 t ha-1 for Mucuna and 2.56 t ha-1 for Canavalia entries were obtained when the cover crops were planted at 6 WAPM. These values however fell short of the sole maize (3.72 t ha-1) but were higher than the national average yield of 1.58 t ha-1 for the 2004 growing season. The present study therefore recommends that Mucuna pruriens var. cocchinchinensis and Canavalia ensiformis could be intercropped at 4 WAPM in maize-cover crop intercrop system with one early hand weeding for good maize grain yield. © 2007 Asian Network for Scientific Information.