Abstract: Garlic tip blight which caused by Pleospora herbarum is one of the important diseases in garlic production in Xuzhou area.In this study,the biological characteristics of Pleospora herbarum and the selection of high efficiency and low toxicity fungicides was studied to provide theoretical basis for safe production of garlic. The biological characteristics of this pathogen was analysed by cross method. The results showed that the best carbon source in this study was D-fructose,and the best nitrogen source in this study was potassium nitrite,and the suitable pH was from 5-12,with colony diameter from 7.55-9.15 cm. Mycelium was not sensitive to the light,but in darkness the colony diameter which was 7.30 cm was the longest;The lethal temperature of the pathogen was 57℃,5 min. The most suitable temperature was 22℃,and the colony diameter was 7.78 cm. The toxicity of five fungicides to Pleospora herbarum was tested by mycelia growth inhibition. The result showed that the toxicity to this pathogen of these 5 fungicides was significantly different.Among the 5 fungicides tested,the highest inhibition effect to mycelia growth of Pleospora herbarum was observed with 96% difenoconazole,the value of EC₅₀ was 0.017 4;The better fungicides followed by was 98% pyraclostrobin,the value of EC₅₀ was 0.892 7;98.4% chlorothalonil,98.5% kresoxim-methyl and 98% carbendazol had the lowest effect and the values of EC₅₀ were 9.959 0,18.080 4 and 45.387 7,respectively.

Key words: Pleospora herbarum, Biological characteristics, Toxicity test

CLC Number: 

• S436.33