喷灌与地面灌溉条件下冬小麦籽粒灌浆过程特性分析

为比较喷灌和地面灌溉条件下冬小麦籽粒灌浆过程特性的差异，进而探讨喷灌对作物产量形成的影响机制，该研究以百农矮抗58为试验材料，采用大田试验的方法，应用Richards模型对喷灌和地面灌溉条件下冬小麦强势粒、弱势粒的籽粒灌浆过程进行了模拟。建立在Richards模型基础上的籽粒生长分析显示：与地面灌溉相比，喷灌处理使冬小麦强势粒、弱势粒的千粒质量均显著性提高。灌浆特征参数的比较表明，喷灌处理使冬小麦强势粒、弱势粒的起始势增强，到达最大灌浆速率的时间提前，平均灌浆速率和最大灌浆速率均增大。阶段灌浆特征参数的比较表明，在籽粒灌浆的前期，喷灌处理使冬小麦强势粒、弱势粒的灌浆持续期缩短，平均灌浆速率增加；在籽粒灌浆的中期和后期，喷灌处理使强势粒的灌浆速率均得到了提高，但对其灌浆持续期没有显著影响，使弱势粒的灌浆持续期均延长，灌浆速率均得到了提高。总体上讲，喷灌处理对弱势粒粒质量的影响程度大于强势粒，表明喷灌提高冬小麦的千粒质量主要是通过提高弱势粒的千粒质量来实现的。

Analysis on grain filling characteristics of winter wheat under sprinkler irrigation and surface irrigation conditions

Taking wheat cultivar Bainong AK58 as test material, a field experiment was conducted to study the grain- filling processes in winter wheat under sprinkler and surface irrigation conditions in order to investigate the differences among grain-filling characteristics of different irrigation methods. The results showed that the data of grain weights were fitted to the nonlinear cumulative Richards growth model as a function of days after anthesis. Grain growth analysis based on Richards equation indicated that compared with that under surface irrigation condition, the final grain weights of the superior and inferior grains on sprinkler irrigation condition was markedly higher. Sprinkler irrigation increased the initial grain growth potentiality, shortened the time reaching the maximum grain filling rates, and enhanced the average and maximum grain filling rates in both superior and inferior grains. The grain filling rates in the superior and inferior grains were increased while durations were shortened on sprinkler irrigation conditions during the early grain filling phase. During the middle and later phases, both the rates and durations of grain filling were increased in the inferior grains under sprinkler irrigation conditions, while the grain filling rates were increased and the grain filling durations were not changed significantly in the superior grains. In conclusion, the magnitude of the effects of sprinkler irrigation on grain filling was quite greater for inferior grains than that for superior grains. The increment of grain weight of winter wheat treated with sprinkler irrigation was mainly realized through increasing grain weight of inferior grains.