Effects of different plant types and planting densities of maize on the yield, nutrient uptake, and utilization of intercropped soybean

Planting density is an important factor affecting the yield potential of intercropping systems. To determine the suitable planting densities for different maize plant types intercropped with soybean, a field experiment was conducted on four planting densities (45 000, 52 500, 60 000, and 67 500 plant·ha^–1) of maize in the intercropping system at same fertilization level, using the pact-type “Denghai 605” (DH605) and flat-type variety “Chuandan 428” (CD428) and fresh soybean as materials. The effects of different plant types and planting densities of maize on aboveground dry matter accumulation, yield, yield components, nutrient uptake, and utilization of soybean were studied. The results showed that both the aboveground dry matter accumulation of different growth periods, yield, number of pods per plant, 100-grain weight, nutrient accumulation, and the partial fertilizer productivity of intercropped soybean were significantly reduced with increasing maize planting density. The effects of CD428 on intercropped soybean were higher than those of DH605 at the same planting density. A combination of yields of the maize-soybean complex population could be given better consideration with the cultivar DH605 at 60 000 plant·ha^–1 planting density intercropped with soybean, and the cultivar CD428 at 52 500 plant·ha^–1 planting density intercropped with soybean.