The Identification of Pathogen and Control of Anthracnose in Pistacia Vera L.
|School||Agricultural University of Hebei|
|Keywords||Pistacia vera L Colletotrichum gloeosporioides identification Biological control chemical control resistance varieties|
In this research, the pathogen, biological characteristics and disease control of anthracnose in Pistacia vera L. were investigated. The main results are as follows:1 Identification and ITS sequence analysis of the pathogen of Pistacia vera L. anthracnoseThe occurrence, symptom characteristics and pathogen identification of anthracnose on Pistacia vera L. in Hebei were studied. This disease caused damage on leaves, fruits and branch. There are brown spot on the leaves and fruits, and canker on branches with transparent exudate. Twenty two strains were collected from two districts from 2005 to 2008 and all isolates showed similar characteristics in colony. They formed gray villous colonies in PDA culture at 25℃after 3~4 d, and orange spore mass appeared after culturing for 5~7 d. This fungus could infect strawberry leaves, but not pepper, grape, Japan euonymus leaves and the fruits of apple. Conidium is long oval or cylindrical with a single cell, 7.9~13.2μm×3.3~4.8μm, blunt at both ends. Appressorium, 3.6~4.8μm×4.2~6.4μm, is dark brown, with nearly round or irregular shape and thick wall. A rDNA-ITS fragment of 583 bp was amplified using the DNA of strain CN504 as a template and sequenced. The obtained sequences was compared with those in GenBank, and we found that 100 ITS sequences with the highest homology belong to Colletotrichum gloeosporioides Penz or the sexual stage of Glomerella cingulata Stenem, and their homology is 98% ~ 99%. According to its characteristics of morphology, pathogenicity and sequence analysis of the internal transcribed spacer region of the ribosomal DNA (ITS), the pistachio pathogen was identified as C. gloeosporioides.2 The Control of Anthracnose in Pistacia veraThe control measures of anthracnose in Pistacia vera L. were investigated for the first time in the research. Inhibition activity, mechanism and control effect of four antagonistic microorganism and eight fungicides to the pathogen of anthracnose in Pistacia vera were studied in detail. The results of control effect in vitro showed that CN068 had the strongest antagonistic activities in the leaves of variety T-491, WCS358::phl had the worse antagonistic activities. Ziram-thira and mancozeb had good effect. Results of control effect in the field shows that two fungicides and their mixture all had distinct control effect. Ziram-thira should be extend because of its best Stability in the control.3 The selection of resistance varieties of Pistacia veraIn vitro inoculations were carried out in the laboratory, and the infection time and area were investigated .The results showed: T-471, T-491, Sinkiang-Best, Varieties-N, M-38, T-662 have the stronger resistance. The performance of field showed T-471, T-11 are strongest resistant varieties. Based on the above-mentioned test, variety T-471 is the most resistant one.