Selecting maize cultivars to regulate canopy structure and light interception for high yield

Under climate change background, long shady days during the summer maize growing season reduce the yield potential of this crop in the North China Plain. Optimizing the canopy structure can increase light interception to mitigate the negative effects of climate change. The spatial arrangement of each leaf along the stem affects the light interception that was influenced by cultivar characteristics. Field studies were carried out to select cultivars to optimize canopy structure in maize (Zea mays L.). Results indicated that the middle-upper canopy above the ear and two leaves below the ear position play a more important role than that of the lower canopy below the ear in deciding the final grain yield. The middle-upper canopy layer had larger leaf photosynthetic potential decided by the larger net photosynthesis rate and leaf area, as compared with the lower canopy. Larger FIPAR (the fraction of the photosynthetically active radiation) and less PAR (the photosynthetically active radiation) observed below the ear position were beneficial for yield improvement. Therefore, optimizing the middle-upper canopy structure by selecting cultivars to construct an ideotype plant in maize should be adopted for higher grain production.