Bacterial Leaf Spot Study On Processing Pepper Of Xinjiang

In2011-2013, the occurrence of bacterial leaf spot was surveyed in Xinjiang Bazhou(Hejing County and HeshuoCounty)and Xinjiang Anjihai Shawan County and others. Found that bacterial leaf spot occured on the north-south borderpepper were widespread and serious, which posed a serious threat to production and had a spread and worsening trend. WhatI studied was to isolate and identifie the pathogenic bacteria, clear its species and genetic differentiation, measured biologicalcharacteristics and host range, analyzes the main factors affected the occurrence of disease and screen an effectiveantimicrobial chemicals, All these were to provide a scientific basis to diagnose and control the disease. The main findingswere as follows:The survey found that pepper bacterial leaf spot may be morbidity from seedling to adult stage, the rate of morbidity inseedling was about15%, some individual fields were up to100%, resulted at least20%to30%production loss. Fromprocessing peppers in Southern and Northern isolated96strains. Identificated morphological, test peppers pathogenicity andmeasured biological characteristics, physiological and biochemical traits. Then I selectd representatives strain to represent16S rDNA and rpoD gene amplification, analysis sequencing and phylogenetic. The southern pathogen was identified asPseudomonas syringae pv. syyringae, northern pathogen was identified as Pseudomonas sp.Part of the biological characteristics and host range of Pathogen P. syringae pv. syringae was measured in this study, theresults showed that the most suitable medium for P. syringae pv. syringae is BPA, growing temperature ranged from25℃to30℃, the most optimum temperature was28℃. Its growing pH ranged from6.5to8.0, the most optimal pH was7. Thepathogenic bacteria growed well under1%NaCl, while more than4%NaCl will inhibition growth. The results showed thatthe isolates not only caused leaf spot symptoms on pepper, but also infected sixteen kinds of plants, such as tomato, eggplant,potato, cucumbers, green beans, cabbage, carrots and celery, et al in artificial inoculation tests. By the16S rDNA PCR-RFLP,16S rDNA sequence analysis, parsed the genetic diversity of strains and the the relationship of system development, revealedthe genetic diversity of the southern and northern strains, and explicited their phylogenetic relationships.By indoor and Greenhouse experiment, the effects of nine fungicides were determined and screening. Invitro experimentshowed that Kocide2000>Copper acetate>StreptomycIN>Copper Hydroxide101>Cupic Hydroxide> Copper Hydroxide2000.Kocide2000and Copper acetate bacteriostatic rate could reach more than97%, EC50values were5.954mg/L and7.439mg/L, Greenhouse tests showed that the control effect of protective spraying(43.34%~80.84%)was better than the controleffect of therapeutic spraying(12.35%~49.54%), which Kocide2000and Cupic Hydroxide had good control effect.