玉米收获期的籽粒含水率是影响收获质量、商品品质和贮藏加工的关键因素，已经成为一个玉米产业发展中重要的技术与经济问题。本试验在大田条件下设置全生育期遮阴试验，通过测定成熟期籽粒含水率，分析遮阴对玉米籽粒含水率的影响。结果表明，在CK、S1和S2处理下，各品种的籽粒含水率表现为郑单958最高、先玉335次之、登海618最低，郑单958籽粒含水率分别比先玉335和登海618平均高出2.26%和9.43%，先玉335比登海618高7.01%；在S3处理下，登海618比先玉335籽粒含水率平均高出4.36%。遮阴后玉米籽粒含水率呈升高趋势，遮阴程度越大籽粒含水率越高，其中，S1（自然光的85%）、S2（自然光的70%）和S3（自然光的50%）处理的籽粒含水率分别比CK（自然光）平均高出2.79%、4.43%和23.83%。种植密度从75000增加到120000株/ ha，登海618、先玉335和郑单958的籽粒含水率分别平均增加了6.63%、1.62%和1.53%，其中，登海618的籽粒含水率增加幅度显著高于先玉335和郑单958。遮阴后弱光胁迫导致玉米成熟延迟，与CK相比，S1、S2和S3遮阴处理成熟期平均推迟了4.0、4.0和6.5d，可能是导致籽粒含水率升高的原因。因此，在阴雨寡照频发和种植密度较高的区域或年份，建议选择熟期更早、脱水快的品种以达到机械粒收的籽粒水分要求。
英文摘要:
Grain moisture content of maize at harvest is the key factor that affects the grain quality, storage and processing which has been an important issue of technique and economic. The experiment was conducted in the field by setting a shading test throughout the whole growth period. We analyzed the influence of shading on grain moisture content of kernels at maturity. The grain moisture content showed a same tendency, Denghai 618 was the lowest, Xianyu 335 was the second and Zhengdan 958 was the highest under the treatment of CK, S1 and S2, respectively. In addition, the average grain moisture content of Zhengdan 958 was 2.26% and 9.43% higher than Xianyu 335 and Denghai 618; Xianyu 335 was 7.01% higher than that of Denghai 618. Denghai 618 was 4.36% higher than Xianyu 335 under S3 treatment. The grain moisture content increased with increasing levels of shading, the grain moisture content of S1 (85% of natural light), S2 (70% of natural light) and S3 (50% of natural light) was 2.79%, 4.43% and 23.83% higher than that of CK (natural light), respectively. With the planting density increased from 75000 to 120000 plants ha- 1, the grain moisture contents of Denghai 618, Xianyu 335 and Zhengdan 958 increased by 6.63%, 1.62% and 1.53%, respectively. The increase degree of grain moisture content of Denghai 618 was significantly higher than that of Xianyu 335 and Zhengdan 958. The weak light stress by shading delayed the maturity of maize, the maturity of S1, S2 and S3 were delayed by 4.0, 4.0 and 6.5 days comparing with CK, which may be the reason for the increase of grain moisture content. It is suggested that selecting cultivars with earlier maturity and faster kernel dehydration rate will meet the requirement of grain moisture for mechanical grain harvesting in the areas where kernel dehydration rate was slowly caused by frequently rainy and lightless weather.
;
