Effects of fruit bags on microenvironment and non-astringent persimmon pigmentation

Abstract：Effects of fruit bags on microenvironment and non-astringent persimmon pigmentation were studied with four kinds of bags. It was found that temperature difference between day and night inside dou- ble-layer bag with red interior layer was greatest among five treatments.Under the condition of sunny days, the temperature increased by 5.8 ℃ and 4.8℃ on September 18 to 21 and October 3 to 8 respectively, compared with that of the control. The effect of plastic film bag and double-layer bag on the moisture re- tention was better, which alleviated the relative humidity stress when air humidity was too low under fine, hot and dry weather. The light in double-layer bags was poor, there were only 0.8% and 0.4% PAR inside double-layer bag with red interior layer and double-layer bag with black interior layer rspectively at 14：00 pm on sunny days compared with the control. Different bagging materials formed different micro-environ- ment, which resulted in different effects on fruit coloring. The peel pigmentation was better in the treat- ment of double-layer bag with red interior layer, followed by double-layer bag with black interior layer. There was less difference between other treatments and control. On September 25, the peel pigmentation was N25B for double-layer bag with red interior layer, and 163B for control . On October 15, the peel pigmentation was 33A for double-layer bag with red interior layer, and N25B for control . It was found that at persimmon late growth stage, carotenoid content increased in all treatments, and paper bags re- duced carotenoids in peel In the late growth phase, the treatments reduced the flavonoid content except double-layer paper bags. Double-layer bag with red interior layer reduced Carotenoids and Flavonoids by 0.0178 mg. g-1 and 0.0706 mg g-1 at maturity compared with control.