Effects of Zinc Fertilizer on Photosynthetic Characteristics of 'Shine Muscat' Grape

Zinc is an essential nutrient for plant growth and development. Zinc deficiency affects plant photosynthesis and nitrogen metabolism. In this experiment, 'Shine Muscat' grape was used as experimental material. Three soil application levels of zinc sulfate were set up, which were 2 kg/667 m2 , 3 kg/667 m2 and 4 kg/667 m2 , respectively. The time of applying zinc fertilizer in soil was 10 days after flowering, and the time of spraying zinc fertilizer was divided into 21 days after flowering, 35 days after flowering, 21 days and 35 days after flowering, respectively, once (twice in total), with no zinc fertilizer as control (CK). The results showed that the application of zinc sulfate 3 kg/677 m2 on soil 10 days after flowering, 0.3% zinc sulfate fertilizer on leaves 21 days after flowering and 35 days after flowering increased zinc content in grape leaves and fruits, and significantly increased net photosynthetic rate of grape leaves.