2008 in Shihezi region table grape the serious rot disease, leading to a large number of cuts or even some orchards absolute production, greatly affected the normal production of grapes. Clear Shihezi region table grape fruit rot disease pathogen, to lay the foundation for future prevention and treatment, we conducted the study. There are three main typical rot symptoms of disease samples separation and purification culture and conventional morphological identification and molecular biological identification through field investigation and to identify the cause of Shihezi region grape rot pathogens: Botrytis cinerea (Botrytis cinerea Pers .), Aspergillus niger (Aspergillus niger) and black Rhizopus (Rhizopus nigricans). Botrytis cinerea, accounting for 65.6%; times Aspergillus niger, accounting for 13.1%; Rhizopus nigricans only 9.8%. The main incentives more and then the number of steroid use, the amount of excessive and early August long drought rain to cause a lot of cracking, and is also closely related with resistant varieties. Aspergillus niger mycelial growth temperature range of biological observations show that the gray mold growth temperature range of 5-30 ℃, the optimum temperature of 20 ° C, and the growth of the pH range 3-9, the optimum pH 5; 5-35 ℃, the optimal temperature was 30 ° C, pH value range of 3-9, the most suitable pH value of 6; Rhizopus nigricans the 15-35 ℃ mycelium could grow, the optimum temperature of 30 ° C, pH The value range of 3-9, and the most suitable pH value of 5. Light conditions had no effect on the growth of three pathogens basic; Botrytis cinerea and Rhizopus nigricans host a wide range of the Aspergillus host range is relatively narrow. Determination of resistant varieties and field incidence survey: red grapes, Kyoho, wood, Cincinnati strong resistance of gray mold Aspergillus niger, seedless purple bacteria three resistance were poor, which is The field incidence basic consistent. Pathogenicity Test cause the Shihezi area grape rot disease pathogen Botrytis cinerea, gray mold of grapes and cotton from different sources. The results showed that the virulence of grapes and cotton, from cotton gray mold and gray mold of grapes from basically the same, and the optimum growth temperature and mycelium growth rate consistent. Cotton gray mold than from grape gray mold sclerotia ability. After DNA extraction and separation of gray mold strains using random primers for RAPD analysis, 8 random primers tested in four to 10 tested isolates DNA have amplified product. Rich genetic diversity in the strains tested, the results showed that in the .37 threshold tested 10 strains can be divided into four RAPD groups (I, II, III, Ⅳ). 1st group including two strains that the No. 1 and 2 strains were separated from the Shihezi area grapes; the first Ⅱ group included three strains No. 7, 8, 10 strains were separated from Shihezi areas of cotton ; Ⅲ groups, including two strains that number 3,9 strains were separated from Shihezi areas on the grapes and cotton; Ⅳ taxa including three strains, namely No. 5,4,6 strains, respectively, from the Ili, separation the Bole and Alar grapes and cotton. Visible the RAPD division of flora and host and geographical contact.
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