Isolation And Identification Of Pathogens Of Capsicum Anthracnose And Screening Of Capsicum Anthracnose Resistant Strains

Pepper is one of the most important horticultural plants,and Pepper Anthracnose will bring great harm to pepper cultivation.In this experiment,the anthrax collected from the Academy of Agricultural Sciences was separated,purified and identified,and the biological characteristics of anthrax were studied.Then,22 pepper materials were used as the research objects to carry out infection tests,and disease-resistant materials were screened out.The main results are as follows:1.The obtained strain is Capsicum red anthracnose(Colletotrichum colloides).It is beneficial to the growth of Colletotrichum in mixed vegetable juice medium(V8),rye solid medium(RA),soybean solid medium(BA)and carrot solid medium(CA),and is more suitable for obtaining a large number of mycelia.Rye solid medium(RA)can promote sporulation of Colletotrichum.The optimum conditions for growth and sporulation were 12 h light,28 C and p H = 7.2.The indoor toxicity tests of five chemical agents,Shigao,Shibaogong,Baitai,Pohein and Tairun,showed that Tairun had strong toxicity and good bacteriostasis effect,while Shibaogong,Pohein and Baitai had better bacteriostasis effect,but the bacteriostasis effect of Shibaogong was worse.3.22 pepper materials were screened for disease resistance.After 7 days of infection,the apparent characteristics of different materials were observed and recorded.The disease index was calculated.No immune materials,3 highly resistant materials,2 resistant materials,4 resistant materials and 13 susceptible materials were found.Among them,Chuannong pickled pepper No.1,Bianjiao and Chaotianhuang are high resistance materials.4.The activities of CAT,POD,SOD and PPO in resistant varieties were higher than those in susceptible varieties.The activities of CAT in high resistant materials,resistant materials and resistant materials after inoculation were higher than those before inoculation,but the activities of susceptible materials after inoculation were lower than those before inoculation.In addition,the activities of POD,SOD and PPO were higher after inoculation than before inoculation.Chitinase and beta-1,3-glucanase showed the same trend after inoculation.After 7 days of infection,the enzyme activities of 3 high resistant materials,2 disease resistant materials and 4 disease resistant materials increased,while the enzyme activities of 11 susceptible materials decreased,less than before inoculation.The content of malondialdehyde,conductivity and PAL activity were higher than those before inoculation.However,the increase of MDA content and conductivity of susceptible materials was greater than that of resistant materials,and the increase of PAL activity of resistant materials was greater than that of susceptible materials.