Study on the Photosynthetic Characteristics of Intercropping System of Maize and Soybean

Intercropping was a kind of planting mode which could intensively use light,heat,fertilizer,water and other natural resources.Different intercropping modes had different influence on the light energy utilization rate of crop group.Under the maize-soybean intercropping mode of 2∶ 2,2∶ 3 and 2∶ 4,taking single cropped maize and single cropped soybean as the control,the effects of different planting modes on the photosynthetic characteristic indexes of maize and soybean were studied.The results showed that intercropping could improve the light energy utilization rate of maize.The photosynthetic rate,chlorophyll content and leaf area index of intercropped maize increased by 22.4%-24.7%,9.2%-12.0% and 0.9%-3.5%,respectively than single cropped maize,and the photosynthetic rate and chlorophyll content differences were significant.Intercropping decreased the light energy utilization rate of soybean.The photosynthetic rate,chlorophyll content and leaf area index of intercropped soybean decreased by 3.5%-12.6%,1.6%-4.0% and 0.3%-0.5%,respectively than single cropped soybean,while the differences were all not significant.In maize and soybean intercropping system,with the increasing of large row spacing of maize,the chlorophyll content and leaf area index of maize increased,the photosynthetic rate of maize increased at first and decreased later,it was the highest in the intercropping system of 2∶ 3,and the photosynthetic rate,chlorophyll content and leaf area index of soybean increased,while the differences in the photosynthetic characteristics indexes among three intercropping modes were all not significant.The light energy utilization rate of maize and soybean intercropping system of 2∶ 3 was the highest.