Studies On Regulation Of Fruit Color Of Melting Peach By Non-woven Bags

Peach (Prunus persica) is one of fruit crops in Rosaceae originating from China. Melting peach produced in Fenghua, NingBo city, Zhejiang province is quite popular due to its juicy tasty, rich nutrition and high quality. Bagging is a common practice for the production of melting peach because it prevents fruits from disease and insect efficiently and keeps fruit in good shapes. However, bagging affects color accumulation in the fruit peel. In this study regulation of fruit color and other quality indexes of ’Hujingmilu’ and ’Yulu’ peach by polypropylene (PP) non-woven bags was studied with the comparison of current commercial yellow paper bag. Effect of early bag removal and different non-woven bags on fruit anthocyanin accumulation and related gene expressions were also studied.The main conclusions drawn from the research are as followed:1. Bag removal at an early period of veraison promoted the coloration of peach fruits. Three types of tested bags, i.e. black and white non-woven bags, and yellow paper bag, resulted in better skin color with7d-and3d-early bag removal in ’Hujingmilu’ peach fruit. Removing the black non-woven bag7d-and3d-early on fruits could help coloring markedly, another two bags were comparatively not that effective. While on ’Yulu’ fruits, removing the black non-woven bag7d-and3d-early had a more remarkable lifting effect than the other two bags.2. Various colored non-woven bags and yellow paper bag had different effects on the fruit coloration and quality. Based on fruit development and ripening,’Hujingmilu’ and ’Yulu’ fruits covered with non-woven bags (except black ones) had a better peel coloration than those covered with yellow paper bag. Especially, the white non-woven bag could produce red peach fruits just as the control group. Moreover, it is interesting to note that fruits in black non-woven bag showed a tempting yellow and white ground color. As an aside, black non-woven bag had2d-or3d-delay or promote the maturation of peach fruits while other bags didn’t. Bagging treatments on peach could effectively maintain the contents of sugar, acid and Vc of fruits.3. The accumulation of anthocyanin in fruit peel of ’Hujingmilu’ and ’Yulu’ differed by various bagging treatments. Fruits in white non-woven bag had the highest content of anthocyanin, which was close to the control ones, followed by fruits in blue and grey non-woven bags. Fruits in black non-woven bag barely had any anthocyanin accumulation. The expression abundance of anthocyanin structure genes in fruit peel changes in the same way as the trend of anthocyanin accumulation caused by different bags. CHS, F3H and DFR had an obvious coherence with anthocyanin accumulation. The absorption curve of bags showed that the higher of the transmittance, the better coloration the fruits are. Thus fruits covered with white non-woven bag were redder than those covered with other bags. The yellow paper bag has a remarkably low ultraviolet transmittance and produced fruits with light color. Ultraviolet were predicted to benefit the coloration of the fruits.