Study on the Biological Characteristics of Maize Curvularia Leaf Spot in Heilongjiang Province

Some biological characters of Curvularia lunata in Heilongjiang province were studied.The results showed that the optimum temperature for pathogen hyphae growth and conidia germination was 25~35℃.The suitable temperature of spore production was 25~30℃.When the temperature was 30℃,colony diameter was largest,spore germination rate was highest,and sporulation was at the peak(for sporulation peak).Spores began to germinate at 25℃ and relative humidity above 96%,with the relative humidity increasing,the germination rate increased significantly.The conidia germination rate was highest in water droplets.The pathogens could adapt wider scope of pH,the optimum pH for mycelial growth and sporulation maximum was 6~8,the suitable pH range for spore germination was 5~8,the best suitable pH was 7.The effect of light was not obvious to pathogen growth,alternating light and dark was good for the formation of spores and the spore germination could be inhibited for the light.