Study On The Resistance Of Colletotrichum Gloeosporioides In Baise Guangxi

In recent years, it is the most common and serious Fungal disease caused by Mango anthracnose by Colletotrichum gloeosporioides (Penz.) Sacc. Baise is the main mango producing areas in Guangxi. In agricultural production, some antiseptic such as propiconazole has had a serious resistance, which greatly affect the quality and yield of mango. The purpose of this study is to mango anthracnose disease resistant chemical pesticides commonly used in research, therefore, to make mango anthracnose resistance risk assessment and provide the basis for the actual production of scientific and rational drug use. The main results obtained are shown as follows:1、It is used growth rate method with prochloraz, pyaclostrobin, propiconazole, difenoconazole azole, azoxystrobin, thiophanate-methyl, chlorothalonil, mancozeb and carbendazim9kinds of antiseptic. Representative for the seven selected strains of BT-1, BJ-3, BG-1, YT-5, YJ-5, DG-3and DT-2make indoor toxicological tests. Strains collected from Baise Youjiang district in the same antiseptic toxicological data measure relative to other strains small.2、Selected indoor toxicological tests, the best is EC, the worst is WP, WDG and SC are in the middle in the nine antiseptic, prochloraz is the best antiseptic, the mean EC50of its indoor toxicological test is0.04μg/mL, the difference between the strains is1.83, both are the smallest of all antiseptic. Prochloraz is the best antiseptic of mango anthracnose in indoor experiment. Carbendazim is the worst antiseptic, the mean EC50of its indoor toxicological test is333.37μg/mL, the difference between the strains is13926.6. But inhibitory effect was much pronounced in strains of BT-1, BG-1, YT-5, YJ-5and DT-2, the mean EC50of its indoor toxicological test is0.1μg/mL.3、Results of resistance selection12generations on strains by prochloraz, pyaclostrobin, propiconazole, difenoconazole azole, azoxystrobin and carbendazim which are better control effect, show that EC50has been growing for all strains. Increase in resistance strains are sparse and no sudden increase in cases, levels of resistance are basically fastest from F6to F12.4、it has cultured non-antiseptic from F13to F18. For carbendazim, levels of resistance strains increase slightly on F15, then decline firstly on F18. Compared with F18, strains decline slightly on F15. For other antiseptic, levels of resistance strains decline slightly on F15, then decline extremely on F18. Through F1to F12with antiseptic, F13to F18with non-antiseptic, levels of resistance strains are less then2, except Individual strains. Resistance strains which are inducted for6kinds of antiseptic, can not stay stable genetically.5、Under the same condition by measuring the biological characteristic of strains, mycelial growth and pathogenic are little different, sporulation capacity is very different. It is found that the resistant strains are decreased in these characteristic, compared with their original strains.6、With better control effect,6kinds of antiseptic conduct risk assessment of resistance. Prochloraz is the lowest, Carbendazim is the highest, other antiseptic is in the middle.