Effects Of Different Plant Growth Regulators On AsA Metabolism In ‘Huping’ Jujube Fruit

Ascorbic acid(AsA)(vitamin C)is a kind of hexose endolipid which plays an important role in antioxidant and metabolic function of organism.To provide theoretical basis for elucidating AsA accumulation rule in ‘Huping’ jujube fruit and establishing enrichment technology of functional active substances.In this paper,‘Huping’ jujube was used as the test material,and different plant growth regulators were treated.The effects of different plant growth regulators on AsA accumulation in jujube fruit were discussed by measuring the internal and external quality,AsA content and metabolic related enzyme activities.The main research results are as follows:1.ABA treatment can affect the activities of Ga ILDH,MDHAR and DHAR enzymes in AsA metabolism,and then affect the contents of AsA and DHA in jujube fruit.From Crisp maturity stage to Ripening stage,ABA treatment reduced AsA content in jujube fruit mainly by reducing the enzyme activity of Ga ILDH in the synthetic pathway.The decrease of DHA content is mainly caused by the decrease of synthetase Ga ILDH,which leads to the decrease of AsA content in jujube fruit.The activity changes of MDHAR and DHAR have limited effect on the changes of AsA and DHA content caused by ABA treatment.2.Sodium naphthalene-1-acetate treatment can affect the activities of Ga ILDH,MDHAR,DHAR and APX enzymes in AsA metabolism,and then affect the contents of AsA and DHA;The decrease of AsA content in jujube fruit by Sodium naphthalene-1-acetate treatment was mainly caused by the decrease of enzyme activity of Ga ILDH in the synthetic pathway from brittle maturity stage to full maturity stage.The decrease of DHA content is mainly caused by the decrease of synthetase Ga ILDH,which leads to the decrease of AsA content in jujube fruit.The activity changes of MDHAR,DHAR and APX have limited effect on the changes of AsA and DHA content caused by Sodium naphthalene-1-acetate treatment.3.KL treatment can affect the activities of Ga ILDH,MDHAR,DHAR and APX enzymes in AsA metabolism,and then affect the contents of AsA and DHA.The main reason for KL treatment to increase AsA content in jujube fruit is to increase the enzyme activity of Ga ILDH in the synthetic pathway.The increase of DHA content is mainly due to the decrease of MDHAR enzyme activity and thus DHA reduction.4.Each treatment had no significant effect on the single fruit weight of ‘Huping’ jujube,while GA3 and Sodium naphthalene-1-acetate increased the fruit shape index,ABA and Sodium naphthalene-1-acetate promoted the decrease of titratable acid content and significantly increased the soluble sugar content of jujube fruit at full maturity,while GA3 and KL increased the titratable acid content of jujube fruit,but had no significant effect on soluble sugar content.