酸性硫酸钙处理对水蜜桃采后匍枝根霉致病力的影响

为研究酸性硫酸钙(ACS)溶液对水蜜桃果实采后致腐匍枝根霉(Rhizopus stolonifer)的抑菌效果,在离体和体内条件下,探究其对匍枝根霉细胞膜渗透率、细胞壁降解酶、呼吸相关酶活性和桃果发病率的影响。结果表明,不同稀释倍数的ACS溶液对匍枝根霉均有不同程度的抑菌作用,其中ACS-10^-3处理组的抑菌效果最强。在作用120 min时,ACS-10^-3组菌丝细胞膜渗透率达到52.76%,较CK高出39.72%;匍枝根霉在含有50%ACS稀释液的带药培养基中培养9 d时,ACS-10^-3组的PG、PMG、C_X和GLU等细胞壁降解酶活性得到了抑制,较CK分别降低38.41%、41.96%、59.31%和35.52%;且在很大程度上抑制了呼吸能量代谢系统中酶活性的上升,培养第9天时匍枝根霉的SDH、MDH和IDH活性分别为0.02±0.01、0.68±0.12、106.13±3.54 nmol·min^-1·g^-1,均显著低于CK(P<0.05)。同时,ACS稀释液可显著降低损伤接种桃果实的匍枝根霉病斑面积和接种发病率,与CK相比,ACS-10^-3组桃果实的匍枝根霉病斑面积和接种发病率分别降低了99.61%和73.33%。因此,适宜稀释倍数的ACS溶液能够有效抑制水蜜桃采后因匍枝根霉侵染引起的软腐病。

Effect of Acidic Calcium Sulfate Treatment on Pathogenicity of Postharvest Rhizopus stolonifer in Honey Peach

This study investigated the effectiveness bacteriostatic of Rhizopus stolonifer with ACS solution on postharvest of peach, to investigated the cell membrane permeability, cell wall degradation enzyme, respiratory related enzyme activity and incidence of peach cased by R. stolonifer under in vitro and in vivo conditions. The results showed that the ACS solution with different diluted concentration had vaired antibacterial effects on R. stolonifer, ACS-10^-3 group turned out to be the most effective antibacterial one. At 120 min, the cell membrane permeability of the ACS-10^-3 group was 52.76%, which was 39.72% higher than that of the control group. When the Rhizopus stolonifer was cultured for 9 days in medicated medium containing 50% ACS dilution, cell wall degrading enzyme activities such as polygalacturonase, polymethylgalacturonase, cellulose and β-Glucosidase in the ACS-10^-3 group were inhibited, which were 38.41%, 41.96%, 59.31% and 35.52% lower than those in the control group, respectively, which also significantly inhibited the increase of enzyme activity in the respiratory energy metabolism system. On the ninth day of culture, the succinate dehydrogenase, malate dehydrogenase and isocitrate dehydrogenase activities of Rhizopus stolonifer were 0.02±0.01, 0.68±0.12 and 106.13±3.54 nmol·min^-1·g^-1, respectively, which were significantly lower than the control group (P<0.05). Meanwhile, the dilution of ACS can effectively reduce the lesion area and incidence of peach fruit damaged by inoculation with R. stolonifer. Compared with the control group, the lesion area and the incidence of peach fruit in the ACS-10^-3 group were reduced by 99.61% and 73.33%, respectively. The results of this study provide a potencial basis for the application of ACS solution in the prevention and controlling of postharvest diseases of peaches and fruits. Therefore, a suitable dilution ratio of ACS solution can effectively inhibit the decay of the honey peaches caused by the infection of R. stolonifer.