小麦籽粒灌浆与脱水特性

【目的】研究小麦品种籽粒灌浆与脱水特性,为培育灌浆快、脱水快的少（免）晾晒小麦品种提供选择方法和理论依据。【方法】2015—2016年以长江中下游地区7个主推小麦品种为试验材料,采用Logistic方程拟合、多重比较及相关分析等方法,测定灌浆与脱水指标,生理成熟期及收获期籽粒含水率等。【结果】籽粒灌浆呈“S”型“慢-快-慢”的增长趋势,但不同品种最大灌浆速率、平均灌浆速率及灌浆持续时间差异显著,扬麦11、扬麦158、扬麦16最大灌浆速率及平均灌浆速率较大,花后30 d籽粒干重均达35 g以上,灌浆持续期较短;扬麦15灌浆速率仅次于上述3个品种,但灌浆持续期最长;宁麦13、扬麦20、扬麦22灌浆速率较小。最大灌浆速率、平均灌浆速率以及渐增期、快增期和缓增期的灌浆速率均与千粒重极显著正相关,3个灌浆时期灌浆速率R2>R1>R3,花后30 d灌浆基本完成。籽粒灌浆完成后进入脱水阶段,生理成熟期和收获期籽粒含水率、生理成熟后籽粒脱水速率品种间差异显著,扬麦11、扬麦158、扬麦16生理成熟后籽粒脱水速率较高,扬麦15最低。收获期籽粒含水率与生理成熟期籽粒含水率、籽粒平均脱水速率、生理成熟后2 d籽粒脱水速率显著或极显著相关。【结论】扬麦11、扬麦158、扬麦16灌浆速率大,灌浆完成早,籽粒脱水快。花后30 d粒重>35 g可作为育种材料灌浆快慢的选择指标,生理成熟期后籽粒平均脱水速率可作为衡量小麦品种脱水快慢的选择指标。

Characteristics of Grain Filling and Dehydration in Wheat

【Objective】The characteristic of grain filling and dehydration in wheat was studied, which provided a selection method and a theoretical basis for breeding wheat variety with fast filling and dehydration, and its grain with safety moisture content without drying process at harvesting date. 【Method】 In 2015 and 2016, 7 main wheat varieties in the middle and lower of the Yangtze River Valley were used as tested materials. The grain filling traits, dehydration rate and grain moisture content at physiological maturity and harvest date were measured to explore their profiles by Logistic Growth Equation (LGE) fitting analysis and multiple comparison and correlation coefficient method. 【Result】 The results indicated that grain-filling of 7 varieties fitted LGE best, with an S-like breakthrough curve of slow-fast-slow trend, but there were significant differences in the maximum grain-filling rate, average grain-filling rate and grain-filling duration in different varieties. The maximum grain-filling rates and average grain-filling rates of Yangmai 11, Yangmai 158 and Yangmai 16 were higher, whose dry grain weights at 30 d after anthesis were more than 35 g and the grain-filling durations were shorter; The grain filling rate of Yangmai 15 was the fourth fastest, but the grain-filling duration was the longest among the 7 wheat genotypes; Ningmai 13, Yangmai 20 and Yangmai 22 had the smaller filling rates, respectively. The maximum grain-filling rate, average grain-filling rate, R1, R2 and R3 were significantly positively correlated with 1000-grain weight. The rate of grain filling was R2>R1>R3 in the three filling stages. The filling grain of wheat was basically finished at 30 d after anthesis. After the grain filling stage, it started the dehydration and drying stage. There were significant differences among the 7 genotypes in the grain moisture content at physiological maturity and harvest date, as well as the grain dehydration rate. The grain dehydration rates of Yangmai 11, Yangmai 158 and Yangmai 16 were higher than the others, whereas Yangmai15 was the lowest. The grain moisture content at harvest date was significantly (P<0.01, 0.05) correlated with the grain moisture content at physiological maturity date, the average dehydration rate after physiological maturity, and the grain dehydration rate at 2 d after physiological maturity.【Conclusion】In Yangmai 11, Yangmai 158 and Yangmai 16, the grain-filling was faster and completed earlier, and the grain dehydrated more quickly. The grain weight >35 g at 30 d after anthesis could be used as the selection parameter of the grain-filling rate. The average grain dehydration rate after physiological maturity could be a selection parameter that evaluates the dehydration property of wheat.