The Optimal Cultivar × Sowing Date × Plant Density for Grain Yield and Resource Use Efficiency of Summer Maize in the Northern Huang–Huai–Hai Plain of China

In order to explore the optimal cultivar × sowing date plant density for summer maize (Zea mays L.) in Northern Huang–Huai–Hai (HHH) Plain of China, field experiments were conducted over two consecutive years (2018–2019) on a loam soil HHH Plain. A split–split plot design was employed this study, and main plots included three cultivars (HM1: early-maturing cultivar; ZD958: medium-maturing DH605: late-maturing cultivar); subplots consisted dates (SD1: June 10; SD2: 17; SD3: 24); sub-sub include densities (PD1: 6.75 104 plants ha?1; PD2: 8.25 ha?1). The results showed that effects grain yield not significant, major factor affecting yield. Delayed significantly decreased maize, due mainly reduced kernel weight, which is associated with lower post-anthesis dry matter accumulation. Moreover, radiation use efficiency (RUE), temperature (TUE), water (WUE) affected by cultivar, date, density. Selecting early- beneficial improvements RUE TUE, grown at earlier higher increased TUE. interactive analysis optimum yields all tested observed SD1-PD2, TUE HM1, ZD958, DH605 SD2-PD2, respectively. differences yield, RUE, among significant. These suggested reasonable dense planting had benefits resource efficiency. adapt mechanized harvesting, moisture harvest would be better choice. Therefore, adopting reasonably pattern production China future.