Abstract: Maize grain maturity was significantly correlated with the heat condition during silking to mature stage. Clarifying the grain filling characteristics of different maize hybrids and their relationship with the temperature of grain filling stage could provide theoretical basis for maize grain development regulation and maturity selection. Field experiments were conducted in Harbin in 2014 and 2015 with 9 maize hybrids to study the grain filling characteristics of different maturity maize hybrids, and the relationship with temperature. The results showed that the maximum grain filling rate(Gmax), grain weight at the time of maximum grain filling rate(Wmax) and average grain filling rate (Gmean) of middle-early maturity hybrids were the highest among the 3 maturity hybrids, while those of super-early maturing hybrids were the second. The active filling stage (P) and effective filling time (t3) increased with the extension of ripening period, and the increase was mainly in the period of late grain filling stage. The active filling stage(P) and effective filling time (t3) was significantly positive correlated with the effective accumulated temperature during middle stage of grain filling period, and significantly negative correlated with the daily average temperature during grain filling stage. The maximum and average grain filling rate were positively correlated with the effective accumulated temperature ≥10℃ during the early stage of grain filling period and daily average temperature during the filling period, which was significantly negative correlated with the effective accumulated temperature ≥10℃ during the middle stage of grain filling period and daily mean temperature during the early stage of grain filling period. In the ecological area with limited caloric resources, the average daily temperature during the late stage of grain filling period of the middle-late maturing hybrids was lower, which was not conducive to grain filling, leading to the grain weight of middle-late maturing hybrids was less than that of the middle-early and super-early maturing hybrids. The prolonged maturity was not conducive to grain weight increase under the condition with limited caloric resources. The middle-early maturing hybrids had obvious advantage in grain filling, and then could obtain higher yield.

Key words: maize, maturity, grain filling, temperature

摘要： 玉米籽粒成熟度与吐丝至成熟阶段热量条件显著相关，明确不同熟期玉米品种籽粒灌浆特性及其与灌浆阶段温度的关系，可为玉米籽粒发育调控和熟期选择提供理论依据。研究以极早熟、中早熟和中晚熟3种熟期类型的9个玉米品种为试验材料，于2014年和2015年在哈尔滨实施田间试验，研究不同熟期玉米品种的籽粒灌浆特性及其与温度的关系。结果表明：3种熟期类型品种相比，中早熟品种的最大灌浆速率（Gmax）、达到最大灌浆速率时的生长量（Wmax）和平均灌浆速率（Gmean）最大，极早熟品种次之，中晚熟品种最小；灌浆活跃期（P）和有效灌浆时间（t3）随品种熟期延长而增加，增加部分主要在灌浆缓增期。活跃灌浆期、有效灌浆期与快增期≥10℃有效积温显著正相关，与灌浆期日平均气温显著负相关；最大灌浆速率和平均灌浆速率与渐增期≥10℃有效积温、灌浆期日平均气温显著正相关，与快增期≥10℃有效积温和渐增期日平均气温显著负相关。在热量资源有限的生态区，中晚熟品种进入灌浆缓增期后日平均气温较低，不利于籽粒灌浆，导致中晚熟品种粒重低于中早熟和极早熟品种；因此，在热量资源有限生态区，一味地延长熟期并不利于粒重增加，中早熟品种具有明显的灌浆优势，从而获得较高的产量。

关键词: 玉米, 熟期, 灌浆, 温度