Effects of Row Spacing and Planting Pattern on Photosynthesis, Chlorophyll Fluorescence, and Related Enzyme Activities of Maize Ear Leaf in Maize–Soybean Intercropping

With the continuous improvement of mechanization level and development new crop varieties, optimal strip width for intercropping crops is important. In this study, field experiments were conducted to analyze effects different row spacings planting patterns on photosynthesis, chlorophyll fluorescence, related enzyme activities maize ear leaves in a maize–soybean system using two (wide–narrow rows 80–50 cm uniform ridges 65 cm) ratios (four four soybean; six soybean). The results showed that pattern wide–narrow-row spacing significantly improved photosynthetic capacity compared with uniform-ridge pattern, along marked elevation values stomatal conductance (Gs), transpiration rate (Tr), (Pn). On other hand, photochemical quenching (qP), actual efficiency (φPSII), maximum (Fv/Fm) also increased, effect D-M6S6 treatment was most significant these parameters. Similarly, phosphoenolpyruvate carboxylase ribulose-1,5-bisphosphate carboxylase/oxygenase increased significantly. Among treatments, yield under highest. Therefore, based spacing, soybean better design semi-arid regions western China.