Photophysiological Mechanism of Dense Planting to Increase the Grain Yield of Intercropped Maize with Nitrogen-Reduction Application in Arid Conditions

Leaf photophysiological characteristics are the main indexes that determine crop yield formation. However, it remains unclear whether photosynthesis is systematically regulated via cropping pattern and nitrogen supply when maize crops planted with a high density. So, field experiment had three-factor split-plot arrangement of treatments was conducted from 2020 to 2021. The plot two patterns included sole wheat–maize intercropping. split application rates: traditional rate (N2, 360 kg ha−1) one reduced by 25% (N1, 270 for maize. split–split three planting densities: density (M1, 78,000 plant ha−1), medium (M2, 10,400 (M3, 129,000 maize; corresponding densities intercropped were 45,000, 60,000, 75,000 ha−1, respectively. grain yield, photosynthetic traits, chlorophyll fluorescence assessed. results showed reduction dense negative impact on individual maize’s photosynthesis. intercropping could alleviate these drawbacks. When grown in system at lower level (IN1M2), traits better or similar those treatment (SN2M1) reproductive growth stage. Moreover, IN1M2 improved light energy distribution among photochemistry, photo-protective heat dissipation process compared SN2M1. A grey relation analysis demonstrated Pn Tr played most significant role group’s productivity. Thus, achieved highest can be recommended as feasible agronomic practice oasis-irrigated regions.