The aim of this research is to identify and select wheat varieties(lines)with constant resis-tance and tolerance to the grain aphid Sitobion miscanthi at the adult stage in the field.In 2020,the re-sistance and tolerance levels of 146 Chinese wheat varieties(lines)were assessed based on the resis-tance 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 rep-resents the loss rate of 1 000 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 re-sults 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 demon-strated tolerance when aphid densities were lower under both natural aphid infestation in 2020 and artifi-cially assisted infestation in 2022 in the field,indicating these wheat varieties(lines)possess both toler-ance 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 1 000 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 tol-erance 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.
wheatSitobion miscanthiresistancetoleranceresistance in the field
维普
万方数据
