UV-B辐射增强对苹果炭疽菌生长特性及其过氧化氢酶活性的影响

Effects of enhancing ultraviolet-B radiation on grown character and catalase activity in Colletitrichum gloeosporiodes

在UV-B辐射增强条件下,在UV-B不同剂量率和不同剂量作用下,研究了苹果炭疽菌(Colletrotrichum gloeosporioildes)菌丝的生长速率、产孢性状、分生孢子的萌发特性和过氧化氢酶活性。实验得出,菌落直径、菌丝体干质量、产孢量、分生孢子的萌发及过氧化氢酶(CAT)活性受UV-B的促进,促进作用与剂量率即单位时间内的辐射剂量呈正相关,同一剂量率的不同剂量对苹果炭疽菌的影响没有显著差异。结果表明,UV-B辐射增加,促进了苹果炭疽的生物积累,抗逆性增强,诱导了抗氧化防御系统过氧化氢酶活性,UV-B对苹果炭疽菌的作用不呈累积效应。

The effects of UV-B radiation on the grown character and catalase（CAT） activity in Colletitrichum gloeosporiodes was studied in this paper. The changes of hyphal growth rate, conidia germination, germ tube elongation and catalase（CAT） activity in Colletitrichum gloeosporiodes exposed to UV-B radiation were investigated. The dosages rate of UV-B radiation were 0 kJ·m^2·d^-1 （CK）, 8.26 kJ·m^-2·d^-1 （UV-BⅠ）, 12.83 kJ·m^-2·d^-1 （UV-BⅡ） and 16.35 kJ·m^-2·d^-1 （UV-BⅢ） respectively. The Colletitrichum gloeosporiodes could not survive when it exposed to16.35 kJ·m^-2·d^-1（UV-BⅢ）. Under 16.35 kJ·m^-2·d^-1 （UV-BⅢ）, with increasing the dosage rate of UV-B radiation, the hyphal growth, conidia germination, germ tube elongation and catalase（CAT）activity markedly increased and were significantly higher than those of CK. But those have not significance on same dosage rate but in different dosage. The results showed that the biosynthesis, the resistance and antioxidant enzyme catalase（CAT） activity of Colletrotrichum gloeosporioildes were increased when it cultured under enhanced UV-B radiation. It was dosage rate not dosage as dominative factor in the practice. It was not cumulative effect of the UV-B on Colletitrichum gloeosporiodes.