Effects of bagging and exogenous 5-aminolevulinic acid treatment on coloration of ‘Yunhongli 2’ | 套袋和外源5-氨基乙酰丙酸处理对‘云红梨2号’果皮着色的影响

Chinese. 以‘云红梨2号’为试材,研究套袋、外源5-氨基乙酰丙酸（ALA）处理对果皮花色素苷含量、花色苷合成关键酶活性、可溶性总糖含量以及内源ALA含量变化的影响,并探讨果皮花色素苷含量与酶活性及可溶性总糖含量的关系。结果表明：在果实着色初期,套袋和外源ALA处理均有明显的促进果皮着色的效果,且两者共同处理促进作用更为显著;随着果实接近成熟,花色素苷含量有所下降。在正常光照情况下,果实摘袋后5 d左右对促进着色效果较好。相关性分析表明,套袋处理的果皮花色素苷含量与苯丙氨酸解氨酶（PAL）活性显著相关;不同处理及对照果皮花色素苷含量均与类黄酮3-O-葡萄糖基转移酶（UFGT）活性显著相关,但与果实可溶性总糖含量无显著相关性。

English. The experiments were conducted on＇Yunhongli 2＇with the bagging and exogenous 5-aminolevulinic acid（ALA）treatment.The content of pigments in peel,activity of key enzymes paticipating in anthocyanin synthesis,and content of total soluble sugar and endogenous ALA were analyzed,and the relationships among content of peel pigments,activity of enzymes and total soluble sugar content were also investigated.The results showed that bagging and exogenous ALA treatment both promoted coloration remarkably at the early stage of fruit coloration,and the effects of using them together was better,and the content of pigments in peel showed dereasing along with the fruit maturation.According to the experiment results,it suggested around 5 days before ripeness,under normal sunshine,as the appropriate time to remove bags for coloration improving.Correlation analysis indicated that the pigments content in peel was significantly relevant to the activity of phenylalanine ammonia lyase（PAL）with bagging treatment;and was remarkably relevant to the activity of UDP glucose-flavonoid-3-o-glycosyltransferase（UFGT）in all treatment,but showed no significant relationship with the content of total soluble sugar of fruit.