Improving maize quality from mechanical grain harvesting by matching maize varieties with accumulated temperature in northeast China

BACKGROUNDGlobal warming has led to methods of planting late-maturing maize varieties in northeast China that have hindered the development of physiological maturity (PM) at harvest and the use of mechanical grain harvesting (MGH). Under these conditions it is difficult to balance the drying characteristics of maize varieties and to make full use of accumulated temperature resources in such a way as to reduce grain moisture content (GMC) at harvest. RESULTSThe effective accumulated temperature (AcT) and the drying rates of different varieties vary. In northeast China, with a GMC of 25%, the growth periods of a fast-drying variety (FDV) and a slow-drying variety (SDV) were 114-192 days and 110-188 days respectively. After PM, the FDV needed 47 days and the SDV needed 51 days to reduce the GMC to be ready for MGH. Harvested with a GMC of 20%, the growth period for the FDV was 97-175 days and for the SDV it was 90-171 days. After PM, the FDV required 64 days and the SDV needed 70 days to reduce the GMC to be ready for MGH. CONCLUSIONMatching cultivars with AcT can help farmers to choose suitable varieties. Promoting MGH may boost maize production, thus ensuring China's food security. (c) 2023 Society of Chemical Industry.