Planting Date Influence on Yield of Drought‐Tolerant Maize with Different Maturity Classifications

Abstract

Core Ideas Planting date had no influence on maize grain yieid.Yield components varied across planting dates.Late‐maturity maize hybrids yielded more than early maturity maize hybrids.Maize grain yield was not influenced by drought tolerance type. Planting date and selection of an appropriate hybrid are critical components in optimizing maize (Zea mays L.) yield. The objective of this study was to determine the influence of planting date on yield and yield components of DroughtGard maize hybrids with different maturity classifications as compared to a conventional maize hybrid. Planting date within year had no influence on maize yields of 10.8 Mg ha−1 in 2013 and 13.6 Mg ha−1 in 2014. Delayed planting reduced 100‐kernel weight by 4.1 to 6.0 g, and bulk density by 1.3 to 1.8 kg m3 in both years. Also, delayed planting reduced the number of ears m−2 by 0.7 in 2014, but had no effect in 2013. Delayed planting decreased kernel depth in 2013 by 0.7 mm, but increased depth by 0.6 mm in 2014. Maize grain yield was correlated with all yield components, but variation of correlation magnitude occurred among yield components across planting dates. The number of ears m−2 was relatively more important for early planted maize (R = 0.58** vs. R = 0.10) while the kernel weight (R = 0.45** vs. R = 0.09), kernel depth (R = 0.48** vs. R = 0.23**), and bulk density (R = 0.66** vs. R = 0.18) were relatively more important for late‐planted maize. No maize yield differences occurred between DroughtGard and conventional hybrids with similar maturity. Planting date had little influence on grain yields for maize following soybean [Glycine max (L.) Merr.] due to grain yield component compensation effects.