Impacts Of Lateral Shoot Treatment On Photosynthesis And Fruit Quality Of Cabernet Sauvignon

In this paper, the inpacts of lateral shoot treatment on the regulation of photosynthesis and storage nutrition in branches, as well as fruit quality of Cabernet Sauvignon after harvest were studied, through controlling the number of leaves on the lateral shoot, in order to provide basis for production by achieving simplify production management, reducing labor costs, as well as controlling growth of young sprout and improving fruit quality. The results were as follows:1. Annual dynamic curve of wine grape leaf net photosynthetic rate exhibited a single peak curve, whereas the photosynthetic rate was affected by lateral shoot treatments.The wine grape leaf photosynthesis of main shoots performed differently with different phenological period. In the period of fruiting period, the largest leave net photosynthetic rate performed at the 5-bit. The leaves at the 7-9 bit performed the low net photosynthetic rate due to that the leaves were in the developmental period. With the development of leaves, the leaves with the maximum photosynthetic rate moved up gradually. Leaves with the maximum net photosynthetic rate in enlargement phase and veraison were the first 7-bit and 9-bit leaves respectively. With the development and aging, the leaf net photosynthetic rate of all the bits in maturity period were decreased, with the net photosynthetic rate of 1-bit leaves treated by keeping 5 leaves and pinching, keeping 2 leaves and pinching, keeping 2 leaves and removing new leaves, keeping 1 leaves and pinching on the lateral shoot, and without keeping any lateral shoot decreased by 29.34%, 25.55%, 32.61%, 38.91% and 39.95% respectively, comparing with that in fruiting period.2. Effects of delaying consenescence of the 2-bit leaves on lateral shoot treatments on leaf net photosynthetic rate of main shoots leaves were performed significantly after enlargement phase. From the enlargement phase, the lateral shoots leaves net photosynthetic rate increased with the development of leaves on lateral shoot, and reached the largest level in veraison, and the net photosynthetic rate of all the leaves in lateral shoot could maintain a high level in maturity. Among all the treatments, the leaves net photosynthetic rate treated by keeping 2 leaves and pinching maintained a relative high level from enlargement to maturity.3. Reserving lateral shoot had positive influence on the fruit quality and nutrients storage in branches to some extent.(1) Keeping lateral shoot treatments was more conducive to the increase in fruit total sugar content and soluble solids content at the late stage of fruit development. Keeping lateral shoot increased total sugar content with the maturity increasing in varying degrees from 28 th August. Comparing with the treatment of without keeping any lateral shoot, total sugar content of all treatments was increased by 9.9%, 17.2%, 7.7% and 12.4% respectively.(2) Reserving lateral shoot leaves improved the nutrition storage in main shoot, especially the treatments of keeping 2 leaves and pinching. After reserving lateral shoot leaves, nutrition storage in main branches were improved in all the treatments, in which the treatments of keeping 2 leaves and pinching in lateral shoot performed the highest increases. Content of soluble sugars, starch, soluble protein and free amino acids were increased by 26.2%, 30.7%, 17.3% and 16.4% respectively. And the followed was the treatments of keeping 5 leaves.