Identification Of Black Rot On Cruciferous Vegetables And The Resistance Of Chinese Cabbage Varieties In Shandong Province

Cabbage Black Rot disease is caused by Xanthomonas campestris , that is a major disease in cruciferous vegetables worldwide. This research paper study on the Separation of disease leaves about the cabbage Black Rot, then we conducted identification of cabbage Black Rot disease , exploration of methods of identification of resistance on Chinese cabbage to Black Rot disease, the identification of resistance on varieties of cabbage and the analysis of changes on defence Enzymes after inoculate Black Rot on Cabbages. The results can be summarized as follows:1. We collected 25 samples of Chinese cabbage Black Rot from different fields of Shandong Province during 2005 ~ 2006 years , such as Taian, Jinan, Yantai,Weihai and so on . With that we gained 65 bacterial strains after separation and purity in the lab. Four bacterial strains were voted in pathogenicity mensurate. morphology observation, Biology characteristic and molecules measure of the four strains (named H9,C2,E3,G2) revealed that Biology characteristic reaction shows four examinated bacterial strain coinciding basically , 16S-ITSrDNA sequence analysis indicates the homologous identity between Xanthomonas campestris pv. campestris in Genbank and pathogenic bacteria is 99.63%. The pathogenic bacteria which arouse Chinese cabbage Black Rot in Shandong Province belong to Xanthomonas campestris pv. campestris.2. Through the use of testing different inoculating methods,inoculated concentrations and Age of Chinese cabbage of vaccination, and other black rot disease resistance seedlings were determined to compare their performance,after that screening a set of rapid and accurate methods of identification of resistance to cabbage seedlings. Identification of resistance of black rot on Cabbage seedlings , That is while in the temperatures ranged from 25℃to 30℃, the suspensions of 3×108 colony forming units/mL were sprayed to the leafs seedlings with four to five, the moisture was kept for 24 to 48 hours.That can be better performance of the situation , In seven days after treatmented , leaves performance typical symptoms,reflect the different resistance to black rot on different materials. It was showed that the technique could be easy to distinguish the resistant differences in different varieties of xanthomonas campestris.3. Through identification of resistance on the 37 varieties of Chinese cabbage in Shandong Province to black rot with this method indicated, results showed that all the performance of the tested varieties were not immune response, the resistance of different varieties of Chinese cabbage represent a certain difference. The percentage of high resistant varieties such as Improved varieties 83-24 , Degao.1 and Zhengwd.12 have high resistance , the following condition index of 30, accounting for the trial of species of 8.1%;The moderate resistant varieties w Xia Yang, Tianzheng Excellence and so on, accounting for the total species of 56.8% ; The disease susceptible varieties Qiangchun, Sijiwang, Jiaobai.8 and other performance flu disease was 27.0% ; highly susceptible varieties Juhong60, Jinxiu, Beijingxiaza56 in the condition index above 70, accounting for the total species of 8.1%.4. We selected resistance and flu disease resistance levels of different materials 6 shares of 37 Cabbage material, after dealed with Black Rot disease pathogens vaccination and not vaccinated (spray distilled water) ,and determine the activity changes of the five kinds of Enzyme before and after vaccination Leaves,such as superoxide dismutase,peroxidase,catalase,polyphenol oxidase,phenylalanine ammonia lyase,then analysis the relationship between the changes and the resistance.