Identification Of Pathogenic Fungus From Post-harvest Apricot Fruit And Effects Of Preharvest Oligochitosan, Salicylic Acid Treatment On Harvesting And Storage Quality Of Apricot Fruits

Saimaiti apricots of XinJiang are taken as the experimental material in this paper,beginning with the controlled the post-harvest diseases.on the one hand to identify the types of post-harvest diseases of apricot pathogens by the traditional method of morphological and molecular biology;The other hand studied the time and way of latent infection pathogens and determined oligochitosan and salicylic acid pre-harvest treatment of latent infection pathogen inhibition.Finally, the effects of pre-harvest oligochitosan and salicylic acid treatment on apricot harvest quality and storage quality were researched Discussed the improving postharvest fungal diseases on apricot fruits by pre-harvest oligochitosan and salicylic acid treatment,and provided a theoretical basis for the prevention of post-harvest diseases.(1) The rotten apricot as the research object in cold storage, through the traditional morphological observation to determined the germs spores. Combined with the molecular biology research, through to the bacteria and rDNA-ITS sequence analysis. Matching with the GeneBank nucleic acid database. It is determined that the Alternaria alternata (Fr.) Keissl, Penicillium crustosum, Rhizopus stolonifer are the disease of apricot fruits.(2) Isolation of latent fungi from buds,floral parts and fruit of apricot during growth showed that A.alternata initially mfected styles and settled in ovary and keeped quiescnt during flowering.A.alternata inefected young fruit through the epiderm but was limited in the subepidemal layer,and levels of inefetion by A.alternata varied with zones of the peel from stilar end to stem end of the fruit during enlagement.At harvest the stilar end of the peel was inefected higher than other zones. The solution with5000molecular weight0.05%density and1.0mmol/L salicylic acid was sprayed and obviously decreased the rate of latent inefetion of A.alternata to apricot fruits during growth,and treatment with0.05%density was found to be more effective to inhibit the infection.(3) Molecular weight of5000with density of0.05%and l.Ommol/L salicylic acid were applied to the apricots in different periods.namely the young fruit period,the stigmas period,the veraison period,and right harvest.Post-harvest apricot fruits were storaged at4℃and90%-95%RH,the shape index,weight, firmness,the weight loss rate,soluble solids,titratable acidity,ascorbic acid content harvest fruit quality and storage quality were measured.Latent infection rate and incidence of disease and the lesion area of apricots inoculated with A.alternata were also measured regularly.The results showed that the solution with5000molecular weight and0.05%density oligochitosan and1.0mmol/L salicylic acid preservative treatment could significantly improved apricots harvest fruit quality and storage quality. Besides,the lantent infection rate,the incidence of disease and the lesion area of apricots inoculated with A.alternata were also reduced efficiently,and the solution with5000molecular weight and0.05%density oligochitosan was the best effect,which is the optimal concentration to keep the quality and imprve the disease resistance of apricot fruit effectively.