Study On The Biological Characteristics Of Valso Canker Of Korla Pear And The Inhibition Of Several Fungicides On It

Pear and its protection forest rot disease harm heavy, difficult to control, has seriouslyrestricted the pear production. Studies on species and biological characteristics of pathogen is themain theoretical basis for disease control. This study collected from pear rot like, throughcomparative observation on the culture shape and morphological features, specific pathogendiversity and dominant populations; the in vitro inoculation method, determination of pear cankerfrom different hosts, and mixed planting fruit trees and pathogenicity between shelter forest, findout the cross infection; using laboratory toxicity control effect test and field, screening of novelfungicides with high activity and low toxicity, to provide basis for production.The results of thisstudy are as follows:1. Pear Valsa Canker from main groups: pear10main planting area acquisition disease like,single spore isolation, received a total of24isolates. A ccording to the colony color, edge shape,hyphal density and spore formation will be divided into3categories, respectively, a gray easyChanbao taxa,21strains, accounting for87.5%; B orange easy Chanbao taxa,1strains,accounting for4.2%; C gray dystocia spore taxa, there were2strains, accounting for8.3%.Choose from3groups of6isolates were pathogenic test, results are pathogenic to pearbranches, but there are differences in pathogenicity.2. The main groups of morphological and cultural characteristics: the Korla Fragrant Pear TreeCanker pycnidia and conidium morphology observation, determine the13-1isolate was pear stemrot bunches spore bacteria (C.carphosperma Fr. shell). The optimum strain temperature range is20-30℃, the optimum pH value5~7, under full illumination and mycelia sporulation up close.3. Cross infection: pear rot pathogenic bacteria of red dates and apple branches strong, walnut andElaeagnus branch of pathogenicity of times, the worst of poplar and willow branchespathogenicity; apple, Elaeagnus angustifolia, poplar, walnut and poplar canker could infect thepear leaves, shoots and fruits, but the infection ability differences.4. Results: the best fungicides screening of antibacterial effect of5selected pesticides in bioassayAmi Miao-shou, Yin Dian, the EC50values were0.0193,0.0312μg·ml-1.field control, AmiMiao-shou, Kai Run, received50times50times scraping therapy treatment effect is the best, thewidth and the cure rate of lesion healing far more than the other treatments and control, canachieve the purpose of prevention and treatment.