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两年来，在弗吉尼亚大田试验条件下，采用不同杀菌剂处理研究不同白粉病成株期抗性在保护小麦籽粒产量方面的效果。于小麦的３—４个生长期，对白粉病发生严重度进行了评估，根据资料计算平均白粉病严重度（ＭＭＳ）和白粉病扩展曲线的面积。感病品种Ｓａｌｕｄａ的平均ＭＭＳ为５．３％，两年内该品种的ＭＭＳ和籽粒产量之间存在着显著的负相关。与全生长季进行防治的小区相比，Ｓａｌｕｄａ未处理小区的产量损失平均为１３．４％。生长季早期和晚期进行白粉病防治对保护Ｓａｌｕｄａ品种的籽粒产量是极其重要的。Ｋｎｏｘ６２的平均ＭＭＳ为２．１％，该品种的病害扩展大于其它成株期抗性品种。两年内，Ｋｎｏｘ６２不用杀菌剂的处理同全生长季进行杀菌剂防治的处理相比，其产量相等。两年内，成株期抗病品种Ｍａｓｓｅｙ、Ｒｅｄｃｏａｔ及Ｈｏｕｓｅｒ的不一处理小区，其ＭＭＳ值都低于１％。大多数的情况下，这些品种的遗传抗性都是相当高的。因此，可以不考虑杀菌剂防治囱粉病对这些品种所带来的益处。在利于白粉病流行的条件下，成株期抗性也是有效的。将成株期抗性转入具有高产潜力的半矮化小麦中，可能会出现具有持久抗性的小麦品种。
In the past two years, different germicides were used to study the effect of adult plant resistance of different powdery mildew on wheat grain yield under the field test in Virginia. The severity of powdery mildew was assessed during the 3-4 growing seasons of wheat, and the average powdery mildew severity (MMS) and the area of the powdery mildew expansion curve were calculated from the data. The average MMS of the susceptible cultivar Saluda was 5.3%. There was a significant negative correlation between MMS and grain yield of this cultivar within two years. The average yield loss in untreated Saluda plots was 13.4% compared to plots in the control of the entire growing season. Preventing and controlling powdery mildew in the early and late growing season is extremely important to protect the grain yield of Saluda variety. The average MMS of Knox62 was 2.1%, and the disease expanded more than other adult-resistant varieties. In two years, Knox62 had no yield of fungicide compared to the fungicide control during the entire growing season. Within two years, the MMS values of all the adult resistant varieties Massey, Redcoat and Houser were less than 1%. In most cases, the genetic resistance of these breeds is quite high. Therefore, the benefits of fungicide against these varieties can be ignored. In favor of the prevalence of powdery mildew, adult plant resistance is also effective. Transferring adult plant resistance into semi-dwarfed wheat with high yield potential may result in a long-lasting wheat variety.