| Strawberry is highly favored by consumers for its unique taste and health benefits.Strawberry is usually cultivated during the winter and early spring season under protected condition in our country.However,pests,diseases,low temperature and low light intensity,etc.,have become the major obstacle that impair fruit quality,due to the simple and lowdegree facilities.GABA(γ-aminobutyric acid),a four-carbon non-protein amino acid,widely exists in animals,plants,and microorganisms.It can enhance plant resistance to biotic and abiotic stress.In this study,the widely cultivated strawberry variety ’ Bebihoppe ’ was used as the experimental material,and the effects of exogenous GABA treatment on the growth,development,and fruit quality of strawberry were explored.This research provides a theoretical reference for applying GABA to enhance the stress resistance and quality of strawberry and other horticultural plants.The main results are as follows:1.Exogenous GABA affects the endogenous hormone content(IAA,ABA,and GA)of winter greenhouse strawberry plants,thereby affecting the morphology of short internodes and petioles,making the petioles of the strawberry plants shorter and thicker,and the internodes thinner and longer.However,it did not significantly affect plant height,root length,leaf size,and morphology.Furthermore,it regulated the growth and reproductive processes of the plant,causing the plant to enter the reproductive growth stage earlier and slowing down the growth of new leaves.It also affected the number of flowers per inflorescence.2.Exogenous GABA enhances the polyamine degradation ability of winter greenhouse strawberry plants,promoting the accumulation of soluble sugars and soluble proteins in the petioles and leaves of the plants.It has relatively less effect on SOD,POD,and CAT enzyme activities,and has no significant effect on photosynthesis.Both 5 m M and 10 m M GABA treatments increased the dry and fresh weight of the plant,root,and crown,while 15 m M GABA treatment showed the opposite effect.However,most of these changes were not significant.3.Exogenous GABA treatment affected the appearance of winter greenhouse strawberry fruit,reducing the single fruit weight and longitudinal and transverse diameters of the fruit,but the effect of the 10 m M GABA treatment was relatively small.GABA also affected the fruit development period and maturity time,as well as the taste and nutritional quality of the fruit.The POD and CAT were significantly affected in the treated fruit.4.Exogenous treatment with 10 m M GABA improved fruit firmness and significantly increased the content of soluble solids,soluble sugars,titratable acids,ascorbic acid,and total phenols,without causing significant changes to the fruit appearance.It also enhanced the overall antioxidant capacity,POD and CAT enzyme activities in the fruit,improving fruit quality.Additionally,it advanced the flowering and maturation time,enabling the strawberries to be marketed earlier. |
