| In order to propose a reasonable row spacing of maize in the soybean/maize intercropping system, a field experiment was conducted to investigate the effect of row spacing of maize on system productivity and interspecific competition, by performing five maize row spacing treatments (D10: 10 cm, D20: 20 cm, D45: 45 cm, D60: 60 cm, D70: 70 cm). The results showed that the intercropping advantage was not affected by maize row spacing, for that the land equivalent ratio (LER) was more than 1. As row spacing increased, the yield of intercropped soybean decreased, whereas that of maize increased, resulting in higher the system productivity. The pod numbers and grain numbers per plant of intercropped soybean were significantly affected by row spacing, pod numbers per plant decreased from 38.5 pods·plant-1 under D10 to 15.8 pods·plant-1 under D70, grain numbers per plant of soybean decreased from 66.6 grains·plant-1 to 26.4 grains·plant-1. As row spacing increased, the grain numbers per spike of intercropped maize increased firstly and then decreased. It was highest when maize row spacing was 60 cm, having 606 grains per spike. Maize row spacing also significantly affected interspecific competition. D45 was more reasonable for maize row spacing in soybean/maize intercropping system, considering system productivity and interspecific competition. |