套袋对黄冠梨果实品质和果皮特性的影响

Effects of bagging on the fruit quality and peel characteristics in Huangguan pear

选择外灰内黑纸袋和外黄内白纸袋对黄冠梨果实进行套袋处理,研究了套袋对果实周围微域环境及成熟期间果皮生理生化和果实品质变化的影响。结果表明:套袋改变了果实周围的微域环境,因天气状况而异。中午时分,套袋后袋内温度均高于外界大气温度,湿度低于外界空气湿度。当袋内温度高于35℃时,无论晴天与阴天,袋内的相对湿度低于50%,外黄内白的袋内高温持续时间长于外灰内黑的袋内的;雨天时,袋内相对湿度高于50%,袋内高温持续时间显著短于晴天和阴天。在果实成熟期间,套袋降低了果肉可溶性固形物、可溶性糖和果皮叶绿素含量、以及过氧化物酶活性和多酚氧化酶活性,且套外灰内黑袋的显著低于套外黄内白袋的处理。套外灰内黑袋的果肉可滴定酸和果皮膜透性显著高于裸果,而套外黄内白袋的表现相反。套袋降低了果皮可溶性酚含量,且套外黄内白的显著低于套外灰内黑袋的。套外黄内白袋的果实淀粉含量高于裸果和套外灰内黑袋的,而套外灰内黑袋的与裸果无显著差异。成熟后期套袋果与裸果的Vc含量无明显差别,2种袋之间的差异不显著。

Two different types of bags, outer gray and inner black paper bag（GB） and outer yellow and inner white paper bag（YW）, were used to study the effect of bagging on mieroenvi- ronment around fruit, physiol-biochemical characteristics of peel and quality of Huangguan pear during maturation. The results indicated that the microenvironment around fruit was var- ied with different bag types. The temperature inside the paper bag was higher than that the outside air temperature, while the humidity was lower at moon time. In the sunny and cloudy days, when the temperature inside bag was beyond 35 ~C as well as the humidity was lower than50%, the duration of the high temperature inside the YW bags was longer than that inside the GB ones. In the rainy days, when the relative humidity was higher than 50%, the duration of the high temperature inside bags was shorter than that in the sunny and cloudy days. During the fruit maturation period, the bagging significantly decreased the soluble solids, soluble sug- ars of flesh and chlorophyll content, the PPO activity and the POD activity of peel as compared with the un-bagged fruits, and especially, above changes in GB bagged fruits were more significant than that in YW ones. However, the titratable acid content of Flesh and cell membrane permeability of peel in GB bagged fruits were significantly higher than in un-bagged ones, and was contrary in the YW bagged ones. The soluble phenolics content of peel was lower in bagged fruits than un-bagged ones, and was lowest in YW bagged fruits. The starch content of flesh in YW bagged fruit was higher than that in un-bagged and GY bagged ones, and was not significantly different between the un-bagged and GY bagged ones. The content of vitamin C of flesh was not changed by bagging at late maturation stage, and was not marked different between the two kinds of fruit bags.