白薇提取液对意大利青霉抑菌机理及脐橙青霉病防治效果的研究

试验以意大利青霉(Penicillium italicum)为供试菌,研究不同白薇提取液浓度对意大利青霉孢子萌发率、菌丝体总糖和可溶性蛋白质含量、苹果酸脱氢酶和琥珀酸脱氢酶活性以及培养液电导率的影响,并观察测定白薇提取液对脐橙青霉病的防治效果。结果显示:白薇提取液能够抑制意大利青霉的孢子萌发,在浓度为50.00 mg·mL-1时,孢子萌发的抑制率高达95.43%,此外,白薇提取液还能增强菌丝体细胞膜渗透性,降低菌丝体总糖和可溶性蛋白质含量以及苹果酸脱氢酶和琥珀酸脱氢酶活性,显著降低果实病斑直径。白薇提取液主要是抑制意大利青霉孢子的萌发、破坏细胞膜结构以及降低能量代谢酶活性,从而扰乱意大利青霉正常生长,减少脐橙青霉病的发生。

Antifungal mechanism of Cynanchum atratum Bunge extracts on Penicillium italicum and control effect on blue mold of navel orange

Penicillium italicum was used to evaluated the effects of Cynanchum atraum Bunge extracts with spore germination, content of total sugar, soluble protein, activity of malatedehydrogenase and succinatedehydrogenase, and electric conductivity of broth for P. italicum as well as the control effect on postharvest blue mold of navel orange. The result showed that the C. atratum extracts could inhibit the spore germination of P. italicum at a rate of even 95.43% when 50.00 mg·mL^-1 of extract was applied. Additionally, C. atratum extracts could enhance the cytomembrane permeability of mycelium and the content of total carbohydrate and soluble protein. Moreover, the activity of malatedehydrogenase and succinatedehydrogenase was decreased and the diameter of spots on fruit was depressed significantly. In summary, C. atratum extracts could disturb the growth of P. italicum and reduced the occurrence of navel orange penicilliosis through mainly inhibition of spore germination, destroying the structure of cytomenbrane, and decreasing the activity of energy metabolism enzyme.