成株期小麦对荻草谷网蚜的田间抗蚜性和耐蚜性评价

An evaluation of resistance and tolerance of wheat varieties to the grain aphid Sitobion miscanthi at the adult stage in the field

为拓展和获取对荻草谷网蚜Sitobion miscanthi表现稳定的小麦抗源,以我国146个小麦品种(系)为材料,利用2020年麦田蚜虫发生严重的机会,采用有蚜株蚜害级别计算抗蚜指数,采用耐蚜值(调查株蚜害级别/千粒重损失率)计算耐蚜指数,以此评估小麦的抗蚜性水平和耐蚜性水平;2022年利用人工辅助接蚜的方法对2020年表现稳定的部分小麦品种(系)的评估结果进行验证。结果显示,在自然感蚜条件下2个试验点6次调查中仅山农116、泉麦31和濮麦116表现稳定的抗蚜性,在人工接蚜时仅郑麦132表现稳定的抗蚜性;中育1220、泰禾麦2号和瑞华1408在自然感蚜时蚜量较低,千粒重损失率低于5.00%,人工接蚜亦表现良好的耐蚜性,表明其兼具耐蚜性和一定的抗蚜性;泰麦601、瑞华592、轮选166和中农麦4007在自然感蚜的高蚜量情况下和人工辅助接蚜时均能保持较低的千粒重损失率(小于15.00%),表明成株期小麦的抗蚜性减弱是一种普遍现象,耐蚜性是比抗蚜性更稳定的遗传特征。

The aim of this research is to identify and select wheat varieties(lines)with constant resistance and tolerance to the grain aphid Sitobion miscanthi at the adult stage in the field.In 2020,the resistance and tolerance levels of 146 Chinese wheat varieties(lines)were assessed based on the resistance index derived from aphid rating scale on infested wheat plants and the tolerance index calculated from tolerance value T(where T=L/cumulative value of aphid rating scale on surveyed plant,and L represents the loss rate of 1000 grain weight).This provided an opportunity for resistance evaluation due to severe aphid occurrence during wheat grain-filling stage in the field that year.The identification results for some consistently resistant and tolerant wheat varieties(lines)in 2020 were further validated using artificial assisted aphid infestation in 2022.During the flowering to grain-filling period of wheat plants in the field,it was found that the wheat varieties(lines)Shannong 116,Quanmai 31 and Pumai 116 exhibited consistent resistance to natural aphid infestation in six replicates across two test sites in 2020,while Zhengmai 132 showed constant resistance to artificially assisted aphid infestation in 2022.In addition,the wheat varieties(lines)Zhongyu 1220,Taihemai 2,and Ruihua 1408 consistently demonstrated tolerance when aphid densities were lower under both natural aphid infestation in 2020 and artificially assisted infestation in 2022 in the field,indicating these wheat varieties(lines)possess both tolerance and low resistance to S.miscanthi.Furthermore,tolerant wheat varieties(lines)such as Taimai 601,Ruihua 592,Lunxuan 166,and Zhongnongmai 4007 maintained lower loss rates of 1000 grain weight(<15%)even when aphid densities were higher under both natural aphid infestation in 2020 and artificially assisted infestation in 2022 in the field.The study confirms that resistance weakening and tolerance are more stable genetic characteristics than resistance alone to aphids during the grain-filling stage of wheat,representing a common phenomenon observed in the tested varieties.