Chemotactic-related Genes Of Meloidogyne Incognita

Root knot nematodes have a wide range of hosts and are difficult to control.Among them,Meloidogyne incognita has seriously damaged the yield of crops and the income of farmers.In this study,regulation function of MAPK gene in the allelopathic chemotaxis of M.incognita was preliminarily identified by RNAi technology,which provided ideas for the prevention and treatment of M.incognita.Based on the screening of C.elegans mutants,the MAPK family genes were related to the chemotactic behavior of nematodes.Homologous genes Mi-mpk-1,Mi-mek-2,Mi-lin-45,Mi-let-60 were cloned from M.incognita.Compound A-1 can effectively attract root-knot nematodes at a concentration of 0.1M,and the attractive rate reaches 29%.Low concentration(0.1%)of resorcinol was used to stimulate nematodes to feed.Larvae J2 were treated with soaking solution containing Mi-mpk-1-dsRNA,Mi-mek-2-dsRNA.Mi-lin-45-dsRNA and Mi-let-60-dsRNA for RNA interference experiments,respectively.Compared with the control,the results of RT-PCR showed that relative expression was decreased by 53.56%to Mi-mpk-1 decreased by 44,47%to Mi-mek-2,decreased by 17.26%to Mi-lin-45,and decreased by 46.88%to Mi-let-60.The experimental results showed that the target genes were successfully inhibited.In the chemotactic experiments,the chemotactic behavior of successftully interfere nematodes to the attracting substance A-1 was significantly reduced-The attracting rate to the attractant A-1 of nematodes treated with Mi-mpk-1-dsRNA and Mi-let-60-dsRNA decreased by 27-42.76%,respectively.The results indicate that these four genes have a regulatory effect on the chemotactic behavior of nematodes.After inoculating nematodes treated with Mi-mpk-1-dsRANA,Mi-mek-2-dsRANA and Mi-let-60-dsRNA respectively,the plant growth was promoted,the galls were reduced by 70.01%-87.67%,and the egg mass were reduced by 31.60%-71.86%?compared with Buffer and NC-dsRNA.The results of this study indicate that the four related genes of MAPK family in the root-knot nematode play a regulatory role in the recognition and infection of host.