外源海藻糖对高温胁迫小麦干物质积累和籽粒灌浆的影响

为明确海藻糖喷施时期及浓度对高温胁迫小麦产量形成的影响，于2020—2021年度以扬麦18、烟农19为供试品种，设置三个海藻糖浓度5 mmol·L^-1（C1）、10 mmol·L^-1（C2）、15 mmol·L^-1（C3），分别在抽穗期（T1）、开花期（T2）、花后10 d（T3）喷施海藻糖，以喷施等量清水为对照，花后15~19 d进行高温胁迫，分析不同处理对小麦干物质积累、分配和产量的影响。结果表明，T1时期喷施海藻糖较T3和T2时期产量增加了0.64%和2.54%。C3浓度处理较C2和C1浓度处理产量提升了2.35%和10.30%；T1时期喷施C3浓度海藻糖小麦产量最高，与对照相比烟农19产量增加了15.87%，扬麦18产量增加了17.75%。T1处理下籽粒干物质分配比例较T2、T3处理分别高0.24%和0.15%，C3处理较C1、C2处理分别增加了3.07%和0.82%；海藻糖处理较对照提高了营养器官中干物质向籽粒的转运量，提升了高温胁迫下小麦干物质积累速率、小麦籽粒平均灌浆速率、有效灌浆时长、最大灌浆速率，延缓了最大灌浆速率出现时间。这说明海藻糖处理能够提高小麦的耐高温性，海藻糖喷施浓度比喷施时期对小麦产量的影响更大。本试验条件下，T1时期喷施C3浓度海藻糖产量最高。

Effect of Exogenous Trehalose on Dry Matter Accumulation and Grain Filling of Wheat under Heat Stress

To clarify the effects of the period and concentration of trehalose spraying on the yield formation of wheat under high temperature stress,the experiment was conducted in 2020-2021 at Huainan National Agricultural Science and Technology Park,Anhui Province,China,with Yannong 19 and Yangmai 18 as the test cultivars.Trehalose was sprayed at the heading stage(T1),anthesis stage(T2),and 10 d after anthesis(T3),with three spraying concentrations of 5 mmol·L^-1(C1),10 mmol·L^-1(C2),and 15 mmol·L^-1(C3),under high temperature treatment from 15 to 19 d after anthesis. The results showed that the yield of wheat treated with alginate in T1 period increased by 0.64% and 2.54%,compared to that in T3 and T2 period,respectively.The yield of wheat treated with C3 concentration increased by 2.35% and 10.30%,compared to that with C2 and C1,respectively. The percentage of dry matter distribution in the grain under T1 treatment increased by 0.24% and 0.15% compared with that under T2 and T3 treatments,respectively; and the percentage of dry matter distribution under C3 treatment was 3.07% and 0.82% higher than that under with C1 and C2 treatments,respectively.Alginate treatment improved the ability of dry matter transfer from nutrient organs to the seeds,which enhanced the rate of dry matter accumulation in wheat under high temperature stress and improved the wheat yield under high temperature stress. The average filling rate,effective filling time and maximum filling rate of wheat grains under high temperature stress increased,and the time to maximum filling rate was delayed. This indicates that alginate treatment can improve the high temperature tolerance of wheat,and the spraying concentration has a greater effect on wheat yield formation,rather than the spraying period.