| Apple has a wide planting area and planting history in the world.Because the fruit is rich in nutrients,refreshing and delicious,and contains a variety of mineral elements,it is loved by people in daily life.Therefore,the apple planting industry has brought huge economic benefits to the society.However,due to the occurrence of post-harvest rot diseases,the quality of the fruit is seriously affected and huge economic losses are generated.Oligomeric proanthocyanidins?OPC?are plant polyphenols widely present in nature and can be used as natural non-toxic antioxidants.They play an important role in removing oxidative free radicals in cells and delaying aging.In this study,the"Gala"apple was used as the experimental material to explore the exogenous?OPC?defense mechanism against post-harvest penicillosis.Using OPC as a new inducer to enhance the defense system of the fruit,it has deeply explored the storage time,storage quality,morbidity,fruit hardness,sugar content,resistance enzymes in the fruit and the expression of the resistance enzyme gene Variety.the result shows:1.Exogenous OPC did not directly inhibit the growth of the pathogenic fungus Penicillium penicillium.But what is interesting is that after(0.05,0.1,0.15,0.2g?mL-1)exogenous OPC treatment,the diameter of the lesions in the treated group was smaller than that in the control group.As the OPC concentration increases,the diameter of the lesion becomes smaller.Apples were treated with 0.05 g?ml-1OPC at25°C.By comparing the diameter of the lesions,it was found that the diameter of the lesions in the treatment group was reduced to 42.56%compared with the control group,and the incidence rate was 75.93%;when OPC treatment was performed at a concentration of 0.1 g?mL-1,compared with the control group,the lesions The diameter was reduced to 67.63%,and the incidence rate was 12.96%.2.Further treatment was carried out with 0.1 g?mL-1OPC and samples of resistance enzyme activity were sampled at?0,1,2,3 and 4 d?time points.It was found that some key resistance enzymes inside the apple fruit,superoxide disproportionation the activities of enzymes?SOD?,catalase?CAT?and glucose 6phosphokinase?G6PDH?were induced to increase.Subsequently,the expression levels of CAT and SOD genes were tested,and the results showed that OPC could increase the expression levels of both genes to a certain extent.That is,OPC can enhance the fruit's autonomous defense system by increasing the resistance enzyme activity and resistance enzyme gene expression.At the same time,it was also found that the hardness after 0.1 g mL-11 OPC treatment was higher than that of the control group,but the quality of the fruit was not affected before and after.Finally,the apple fruit was treated with 0.1 g mL-11 OPC and then infected with Botrytis cinerea and Alternaria alternata.Both the incidence and diameter of lesions were lower than the control group.In summary,the data show that exogenous OPC can be used as an inducer to improve the ability of apple fruits to resist the invasion of disease-causing pathogens.Therefore,the research results provide a new basis and direction for the prevention and treatment of post-harvest fruit rot. |
PDF Full Text Request