内蒙古地区根结线虫致病性及不同品种辣椒抗病性评价OA

Taking the Meloidogyne incognita populations isolated from soil samples collected from high-incidence areas of root-knot nematode diseases in Chifeng,Baotou,Hohhot,and Tongliao in Inner Mongolia as test materials,a pot identification method was adopted to conduct experiments on cucumber physiological indicators and host root responses.The study investigated the effects of M.incognita populations from different geographical origins on cucumber growth and development,established an evaluation system,and further evaluated the disease resistance of 36 pepper germplasms using a combination of pot and field experiments,in order to provide a reference for the breeding of pepper varieties resistant to root-knot nematodes.The results showed that,1)pathogenicity varied significantly among different geographical populations,with the BT population being the most virulent.After inoculation,cucumber root length,root surface area,and root volume decreased by 87.8％,86.5％,and 83.4％,respectively,and the disease index reached 87.407;2)the disease index showed a highly significant negative correlation(P＜0.01)with total root length,root surface area,root volume,and fresh root weight,indicating that these root traits,together with the disease index,can form a comprehensive evaluation system for the pathogenicity of root-knot nematodes;3)multiple resistance evaluation of pepper identified seven varieties,LTCP2、LSP8、LSP5、LSP3、CP1、CP6 and LSP6,as highly resistant(HR),with low disease index(0-20.00)and root galling index(0-1.00).Among them,CP1,CP6,and LSP6 exhibited significantly stronger resistance than the resistant control PM 687(disease index 29.41,root galling index 1.47).