不同播期玉米籽粒产量和籽粒水分变化及其叶片、茎秆特性的关系研究

以郑单958、先玉335、庐玉9105、中玉303为材料，设置早播、晚播2个播期，通过2020、2021年两年田间试验，研究了不同播期下玉米籽粒产量、籽粒水分变化与其叶片和茎秆特性的相关关系。结果表明：不同玉米品种早播的GY显著高于晚播，而GW早播低于晚播。随着播期的推迟LAI呈下降趋势，适时早播有利于延缓叶片衰老过程，维持较高的LAI。早播显著增加玉米品种茎秆的RPS和BS，提高茎秆的强度，增加茎秆抗倒能力，晚播则玉米的倒伏风险增加。灌浆期玉米品种间的平均HGW呈逐渐升高趋势，而GW呈逐渐下降趋势。相关性分析显示，GY和GW之间呈负相关未达显著水平，GY与LAS、GFR、BS呈显著正相关，LSR与GY呈负相关关系。GW与LAM、BS、GFR呈显著正相关，而与LSR呈显著负相关。这表明强壮的茎秆可提高玉米抗倒能力，增加玉米籽粒产量，但造成收获籽粒含水率较高。玉米品种要达到籽粒高产量与低水分协同共存必须具有籽粒灌浆快、灌浆期长及成熟时脱水快的特点，调整播期可使高GY和低GW有效协同，以适应籽粒机械收获的要求。

Correlation Between Grain Yield and Grain Moisture,and Leaf and Stem Characteristics in Maize Cultivation at Various Sowing Dates

This study investigated the relationship between grain yield and grain moisture changes, and leaf and stem characteristics under different sowing periods, using Zhengdan 958, Xianyu 335, Luyu 9105, and Zhongyu 303 as materials, with early and late sowing periods. Field experiments conducted in 2020 and 2021 showed that early sowing significantly increased grain yield (GY) compared to late sowing, while grain moisture (GW) was lower in early sowing. Leaf area index (LAI) decreased with the delay of sowing period, and timely early sowing was beneficial for delaying leaf senescence and maintaining a higher LAI. Early sowing significantly increased the root pull strength (RPS) and bending strength (BS) of maize stems, improving stem strength and increasing stem lodging resistance, while late sowing increased the risk of maize lodging. The average harvest grain weight (HGW) among maize varieties showed a gradually increasing trend during the filling period, while GW showed a gradually decreasing trend. Correlation analysis indicated a negative correlation between GY and GW, but it was not significant. GY was significantly positively correlated with leaf area size (LAS), grain filling rate (GFR), and BS, while it was negatively correlated with the leaf/stem ratio (LSR). GW was significantly positively correlated with leaf area mass (LAM), BS, and GFR, while it was significantly negatively correlated with LSR. This study suggested that strong stems can increase maize lodging resistance and grain yield, but can result in higher grain moisture content at harvest. To achieve high grain yield and low moisture content, maize varieties must have the characteristics of fast grain filling, a long filling period, and rapid dehydration at maturity. Adjusting sowing periods can effectively coordinate high GY and low GW to meet the requirements of mechanical grain harvesting.