杏果实发育过程中果胶组分及酶活性变化分析OA北大核心CSTPCD

[Objective]To explore the changes of pectin components and content in apricot fruit develop-ment and the influence on fruit hardness.[Methods]In this study,three apricot varieties,'Kuqa County White Apricot','Luntai white Apricot'and'Dried apricots on the tree Apricot',were selected as experi-mental materials.The relationship between the changes of pectin composition and content and the changes of fruit hardness was analyzed by measuring the growth quality indexes,pectin composition and content and the activity of pectin metabolizing enzyme during the development of apricot fruits.[Results]The results showed as follows:Compared with the other 4 growth stages,the fruit hardness of 3 apricot varieties decreased signifi-cantly at the ripening stage(P<0.05).During fruit development and ripening,PME activity of the three a-pricot varieties showed a decreasing trend,and fruit hardness was significantly positively correlated with PME(P<0.05),while fruit hardness was significantly negatively correlated with ion-bound pectin content and covalently bound pectin content(P<0.01).[Conclusion]During fruit development,the fruit hardness of the three apricot varieties is negatively correlated with the content of ion-bound pectin and covalently bound pectin(P<0.01),which has a great influence on the fruit hardness.Ionic pectin(ISP)has a small molecu-lar weight and is easily soluble in water.The larger the ISP proportion in pectin,the softer the fruit texture.The decrease of hardness of'Luntai white Apricot'and'Dried apricots on the tree Apricot'was mainly caused by PG,while that of'Kuqa County White Apricot'was mainly causedy PL.The hardness of'Luntai white Apri-cot'decreased with the increase of PG activity since the hardcore stage.But in'Dried apricots on the tree A-pricot',PG activity even decreases significantly after young fruit stage,increases significantly after turning color stage,and hardness decreases.The PG activity of'Luntai white Apricot'should be inhibited after the hardcore stage,and that of'Dried apricots on the tree Apricot'should be inhibited after the turning stage.The PL activity of'Kuqa County White Apricot'is always higher,and it needs to inhibit PL activity in pectin.