Effect Of Soil Moisture And Cultural Environment For On Grape Quality And Soil Respiration

Grape was a very popular fruit, which was rich in nutrition value and health value. In recent years, the acreage and yield of grape increased rapidly in China, especially in Shaanxi Province, and its good economic benefits had brought huge economic returns for orchardists. However, there was a phenomenon that the quality declined while the production increased, that was due to the lack of agricultural technology and orchardist planting level. Therefore, it was very worthy of studying the effect of soil moisture and cultural environment on grape quality and soil respiration. It would help to create high- efficient cultivation system of grape.In this study, "Hutai 8th" grape was as the experiment materials. The grape was cultivated under three soil moisture(A:80%~95% SRWC, B:60%~75% SRWC, C:40%~55% SRWC, SRWC represented soil relative water content) and two cultivation environment(Greenhouse, Canopy), three repetitions each treatment. Field observation and laboratory analysis was conducted for two consecutive years in 2014 and 2015. In this study, the nutritional quality, yield, photosynthesis and so on were studied. The main results were as follows:The nutrition quality, secondary metabolites content, yield and soil respiration rate of grape were influenced by different cultivation environment. Through the comprehensive statistical analysis of the data it could be concluded that the comprehensive membership function value of grape under the greenhouse cultivation environment was significantly high, and the comprehensive quality was better than that under canopy cultivation environment.In terms of the nutrition quality of grape, the content of soluble sugar, soluble protein and soluble solid content were higher in proper water deficit(60%~75% SRWC), but Vitamin C content was negatively correlated with soil water content, the lower the soil moisture content, the higher the Vitamin C content. The least organic acid was produced by 60%~75% SRWC under the greenhouse environment, and the difference of organic acid content each treatment in canopy environment was not significant.Under appropriate water deficit(60%~75% SRWC), the difference of grape yield with high water was not significant, but its water consumption was significantly lower than that of 80%~95% SRWC so that the water use efficiency of 60%~75% SRWC was significantly higher than that of the other two treatments. Comparison of different cultivation environments obtained that the yield and water use efficiency of grape in greenhouse was higher than that in canopy under the same soil water.The responses of resveratrol and procyanidine to the soil water content were different under different cultivation conditions. In greenhouse environment, the content of resveratrol and procyanidine decreased with the decrease of soil water content, the content of the both two in canopy environment was the highest under 60%~75% SRWC.The photosynthetic rate of grape increased firstly and then decreased. It could find that the membership function value of grape leaf photosynthetic rate in greenhouse environment was significantly higher than that in canopy environment through a comprehensive analysis. The response of photosynthetic rate of grape leaves to soil moisture content was basically same under the two planting conditions, which was both significantly higher under 60%~75% SRWC. The response of soil respiration to soil moisture content and cultivation environment was similar to the photosynthetic rate, grape soil respiration rate in greenhouse was significantly greater than that in canopy. The difference of soil respiration rate between 80%~95% SRWC and 60%~75% SRWC in greenhouse was not significant, but from the aspect of water saving and high efficiency, 60%~75% SRWC was optimum.In summary, growth environment was more suitable and nutrients accumulated better in the greenhouse than that in the canopy. 60% ~ 75% SRWC of the soil moisture content of grapes could not only produce more nutrients, but also could accumulate more resveratrol, procyanidine and other secondary metabolites with important medicinal value.