UV-B辐射增强对水稻稻瘟病菌(Magnaporthe grisea)生长和产孢的影响

采用人工紫外灯照射方法,研究了在UV-B辐射增强条件下和UV-B不同剂量作用下,水稻稻瘟病菌(Mag-naporthe grisea)菌丝的生长速率、菌落直径、菌落形态、菌丝形态及产孢量。结果表明,UV-B辐射增强可延缓稻瘟病菌的生长,导致菌丝生长速率和产孢量均显著下降(P<0.05)。同一UV-B辐射强度下,不同的辐射时间对稻瘟病菌菌丝生长速率和菌落直径的影响没有显著性差异(P>0.05)。在2.5和5.0 kJ.m-2强度下,不同的辐射剂量对病菌产孢量的影响有显著性差异(P<0.05)。在UV-B辐射增强条件下,病菌采取与植物类似的形态学变化来抵御UV-B辐射增强的伤害,经UV-B辐射处理后的病菌菌落颜色加深,菌丝分布更加致密。

Effects of Enhanced UV-B Radiation on Growth and Sporulation Quantity of Blast Isolate Magnaporthe grisea

The effects of UV-B radiation on the grown character and the spore quantity of blast isolate Magnaporthe grisea were studied. Results showed that supplemental UV-B radiation resulted in growth slowly, decreased in hypal growth rate and sporulation quantity of Magnaporthe grisea (P<0.05) significantly. Under the same intensity of UV-B radiation, difference in radiation time on hypal growth rate and colony diameter of Magnaporthe grisea was not observed (P>0.05 ). Under 2.5 and 5.0 kJ·m~(-2), with increasing the dosage of UV-B radiation, sporulation quantity markedly decreased and was lower than that of CK significantly. Under enhanced UV-B radiation, Magnaporthe grisea had morphological adaption to alleviate UV-B injury. UV-B radiation resulted in darker colony color and more dense distribution of hyphal.