Waxy Maize Yield in Response to a Novel Plant Growth Regulator and Plant Density

High crop density often weakens plants, thereby leading to an increased risk of lodging and reductions in crop yield. In this study, the effects of a novel plant growth regulator, DHEAP [N, N-diethyl-2-hexanoyl oxygen radicals-ethyl amine (2-ethyl chloride) phosphoric acid salt], on waxy maize yield and lodging was evaluated. The field experiment was conducted at two locations (Changping and Wuqiao, China), four plant densities (4.5, 6.0, 7.5 and 9.0 plants m(-2)) and three cultivars (JHN 2008, JKN 2000 and JKN 928) in 2015. After foliar spraying with DHEAP during the 8-leaf stage, fresh ear and grain yield, yield components, and lodging percentage were determined for all cultivars. Grain yield showed a significant increase (3.47%), thousand-kernel weight and kernel number per ear increased by 6.10 and 3.21%, respectively after DHEAP treatment. The optimal plant density ranged from 6.0 to 7.5 plants m(-2). DHEAP significantly decreased waxy maize lodging percentage for all cultivars. Among the maize cultivars, the yield of the compact short plant cultivar JKN 928 was higher than that of JKN 2000 and JHN 2008. It is concluded that optimized plant density might enhance waxy maize yield with a single application of DHEAP before jointing stage. (C) 2019 Friends Science Publishers