Effects Of Fruit Bagging And Preservatives Treatments On Physiological Characteristics Of Pear Fruit During Storage

Oriental pear'Yali'pears and western pear'Xiufeng'pears were used to study the effects of fruit bagging and preservative treatments on the two kinds of pear during storage.Epicuticular wax, total polyphenols, antioxidant activity and volatiles as well as changes of the fruit qualities and relative enzymes were studied. The main results as the following:(1) Fruit bagging had imporved significantly the appearance quality of both the two kinds of pears, reduced the size of fruit lenticel and with tidy edges, smoothened the waxy surface and declined the content of pigments significantly.(2) SEM images showed that cuticle waxes of bagged fruits were much less than that of the control, and the bagged had more and deeper cracks in the fruit surface; had a higher water loss rate. Wax contents and waxy structure changed during the storage.(3) Fruit bagging reduced the volatile compounds and their levels of both the'Yali'and'Xiufeng'pears. But removing bag before harvest would regain the mostly volatiles. The main volatiles of Yali pear were butyl acetate, Acetic acid, hexyl ester, alpha-Farnesene, 2-Hexenal and propyl- Cyclopropane, while the main volatiles of'Xiufeng'pears were mainly in esters: butyl acetate, Acetic acid, hexyl ester, alpha-Farnesene, Octadeamethyl-cyclononasiloxane. Volatile reduced significantly when treatmened by 1-MCP, SNP and SA.(4) Both the contents of total phenols and flavnoids of'Yali'pears and'Xiufeng'pears decreased during the storage.1-MCP treatment can significantly improve storage ability of the later, but did not affect the former obviously. Total phenols, flavnoids and antioxidant activity of fruit were not affected by 1-MCP.(5) Fruit bagging decreased significantly polyphenols in fruit. 1-MCP and SNP improved polyphenols content, total flavonoids content and radical scavenging capacity during the early days of storage, while SA treatment had no such effects.