Screening and evaluation for antibiosis resistance of the spring wheat accessions to the grain aphid,Sitobion miscanthi (Takahashi) (Hemiptera: Aphididae)

Resistant cultivar deployment is an effective method for cereal aphid management.  Under greenhouse conditions, preliminary antibiosis resistance screening was conducted on 114 Ethiopian and 22 Chinese spring wheat accessions.  After performing a bioassay to determine antibiosis resistance, aphid feeding behaviour and phenolic acid content analyses were performed on the aphid resistant wheat accessions by electrical penetration graph (EPG) and high performance liquid chromatography (HPLC), respectively.  Among the wheat accessions, two high resistances, 27 moderate-resistances, and 35 low-resistances to Sitobion miscanthi were identified.  The antibiosis resistance test showed prolonged pre-adult and pre-reproductive periods, shorter reproductive periods, lower fecundity, an intrinsic rate (r_m) of increase, and a finite rate (λ) of increase of S. miscanthi on Lunxuan 145, Wane, Lunxuan 6, 204511, Lunxuan 103 and 5215 than those on the aphid-susceptible accession Beijing 837.  The changes for the parameters of aphid feeding behaviour, including spending a longer time in the penetration and phloem salivation phases and less time in the phloem sap-feeding phase on the resistant wheat accessions, the aphid resistance may occur during the phloem phase and may be due to mechanicalAdditionally, the HPLC analysis showed higher contents of: 1) ferulic acid in Lunxuan 145, Lunxuan 103 and Lunxuan 6; 2) p-coumaric acid in Lunxuan145; 3) vanillic acid in Lunxuan 145, Wane and Lunxuan 6; 4) syringic acid in Lunxuan 103; and 5) caffeic acid in 5215.  The contents of some phenolic acids within wheat leaves, such as p-courmaric acid and vanillic acid showed significant positive correlation with the duration of aphid development, but negative correlation with the aphid fecundity.  The concentrations of these acids may be the causes of antibiosis resistance to S. miscanthi.  The identification of grain aphid-resistant wheat accessions in our study will be helpful in future breeding program for pest control.