关键发育期干旱对春玉米产量及籽粒品质的影响

Effects of drought stress at key growth stages on yield and grain quality of spring maize

为探明不同发育期不同干旱条件对春玉米产量及籽粒品质的影响,以"丹玉405"为试验材料,利用大型农田水分控制试验场,在春玉米拔节、抽雄、乳熟三个关键发育期分别开展中度和重度干旱胁迫对比试验,分析干旱对玉米产量及结构性状、籽粒含水量和品质组成的影响。结果表明:与水分适宜对照相比,其他处理下,干旱导致玉米秃尖比、籽粒氨基酸和粗蛋白含量明显增加,分别平均增加85.3%、10.6%和14.9%;导致百粒重、理论产量、籽粒含水量、淀粉含量明显降低,分别平均降低14.2%、30.5%、29.7%、45.2%,对果穗长、果穗粗以及籽粒脂肪含量总体影响不大;籽粒淀粉含量对拔节期干旱最为敏感;果穗粗、秃尖比、籽粒含水量、脂肪含量及氨基酸含量则受抽雄期干旱影响最大;而果穗长、百粒重、产量及籽粒粗蛋白含量对乳熟期干旱最为敏感。随着干旱程度的增加,玉米产量及籽粒品质受影响程度普遍呈增加趋势,对籽粒品质的影响比对产量的影响更为显著。研究结果为今后高产和优质玉米生产奠定基础,为分析农业生产对气候变化的响应机制提供重要的理论依据。

To explore the effects of different drought conditions at different growth stages on the yield and grain quality of spring maize,a comparative experiment of moderate and severe drought stress was conducted using cultivar Danyu 405 to analyze the effects of drought on maize yield and structural traits,grain water content,and quality composition at three key growth stages( jointing,tasseling,and milking stages) of spring maize. The results showed that drought significantly increased maize bald tip ratio,grain amino acid,and crude protein content by 85.3%,10.6%,and 14. 9% respectively. Drought significantly decreased 100-kernel weight,theoretical yield,grain water content,and starch content by 14. 2%,30. 5%,29. 7%,and 45. 2% respectively.Drought had minor effects on ear length,ear thickness,and grain fat content. Grain starch content was most sensitive to drought during jointing stage. Ear thickness,bald tip ratio,grain water content,fat content,and amino acid content were most affected by drought during tasseling stage,while ear length,100-grain weight,yield,and grain crude protein content were most affected by drought during milking stage. With the increases of drought degree,the yield and grain quality of maize were affected more,with the effects on grain quality being more significant than that on yield. Our results lay a foundation for future high-yield and high-quality maize production and provide an important theoretical basis for understanding the mechanism underlying the responses of agricultural production to climate change.