分期播种对夏玉米产量及品质的影响

探究气候变化背景下不同播种时期对夏玉米干物质积累、产量和品质的影响。以‘登海605’为试验材料，设置4个播种时期：5月31日（播期1,S1）、6月10日（播期2,S2）、6月20日（播期3,S3）和6月30日（播期4,S4），研究不同年份气候背景下不同时期播种对夏玉米株高、叶面积指数、干物质积累分配、籽粒灌浆特性、产量及品质形成的影响。不同年份间、不同播种时期夏玉米产量表现不同，2018年夏玉米S3田间产量较高，2019年S1产量最高，并且其产量高于其他年份，2020年S2产量最高，并显著高于其他播期。玉米群体产量与积温显著相关，果穗粗与降水显著相关，与日照极显著相关；果穗长与日照显著相关。不同播期对籽粒蛋白质、脂肪及淀粉含量产生影响，对粗纤维含量影响较大，积温与籽粒脂肪和粗纤维含量显著相关，日照与籽粒淀粉含量显著相关。播期对株高影响相对较小，对叶面积指数影响较大，适期播种可有效增加玉米叶面积指数及生物量，2018年S2和S3叶面积指数显著高于其他水平，尤其S3叶面积指数均高于本年度其他播期，收获期穗部干物质积累量较高，产量高于其他播期。适期播种能够充分利用当地气候条件，提高夏玉米对光...

The Effects of Staged Sowing on Yield and Quality of Summer Maize

The objective of the study is to explore the effects of different sowing dates on dry matter accumulation, yield and quality of summer maize under the background of climate change. ‘Denghai 605’ was used as the test material, four sowing dates were set: May 31 (sowing date 1, S1), June 10 (sowing date 2, S2), June 20 (sowing date 3, S3) and June 30 (sowing date 4, S4), to study the effects of different sowing dates on plant height, leaf area index, dry matter accumulation and distribution, grain filling characteristics, yield and quality formation of summer maize under different climate backgrounds in different years. The yield of summer maize varied from year to year at different sowing dates. The yield was higher under S3 in 2018. S1 had the highest yield in 2019, which was higher than that of other years. S2 had the highest yield in 2020, which was significantly higher than that of other sowing dates. Maize population yield was significantly correlated with accumulated temperature, ear diameter was significantly correlated with precipitation, and extremely significantly correlated with sunlight; ear length was significantly correlated with sunlight. Different sowing dates had an impact on the content of grain protein, fat and starch, and had a greater impact on crude fiber content. Accumulated temperature was significantly correlated with grain fat content and crude fiber content, and sunlight was significantly correlated with grain starch content. The effect of sowing date on plant height was relatively small and the effect on leaf area index was large. Sowing at the right time could effectively increase the leaf area index and biomass of maize. Leaf area index was significantly higher under S2 and S3 in 2018, especially the leaf area index under S3 were higher than that of other sowing dates in this year, the ear dry matter accumulation was high at the harvest stage, and the yield was higher than that at other sowing dates. Sowing at the right time can make full use of local climatic conditions, improve the utilization of sunlight, temperature and water resources by summer maize, promote the transfer of photosynthetic assimilates from the leaves to the ears, and increase the rate of grain filling, thus effectively increasing grain weight and ensuring the formation of yield and quality.