Effects Of Regulated Deficit Irrigation On Wine Grape Comprehensive Characteristic And Wine Quality

Aimed at wine grape main cultivation area existed the question of water wastage caused by flood irrigation,wine grape quality instability and low quality of wine at the eastern foot of Helan Mountain in Ninxia,used 5-year-old wine grape variety "Cabernet Sauvignon "as the test materials and using the field text under the condition of irrigation technique combined the methods of Regulated Deficit Irrigation degree and the key stages of Regulated Deficit Irrigation,which studied the effects of Regulated Deficit Irrigation on growth,yield,and quality of wine grape and wine quality in order to determine the optimal regulation deficit irrigation degree and period.Meanwhile,revealed the relationship between Regulated Deficit Irrigation and various indexes,established a stable system of regulated deficit irrigation and perfected the corresponding wine grape quality monitoring system,ultimately,provided scientific theory basis for promoting water-saving irrigation and high quality and efficient cultivation of wine grape in the eastern of Helan Mountain.The specific research results are as follows:(1)Effects of Regulated Deficit Irrigation on wine grape growth and development:With the increased of Regulated Deficit Irrigation degree,axillary shoot length,new shoot length and axillary shoot number all had a decreasing tendency,also Inhibited the increase of leaf area,especially 50%CK treatment reduced leaf area by 14.42%compared to CK,90%CK treatment increased the total nitrogen,total phosphorus content of petiole,The key period of Regulated Deficit Irrigation benefited to the raise of total potassium content of petiole compared to 80%CK treatment(setting-expansion period irrigated 5 times and expansion-coloring period irrigated 4 times),at the same time,significantly reduced the number of autumn shoots occurred,expansion-coloring period irrigated 3 times helped to increase the 100 leaves fresh weight.(2)Effects of Regulated Deficit Irrigation on physiological function of wine grape:SPAD value showed the reducing trend as the increased of Regulated Deficit Irrigation degree,leaf net photosynthetic rate and transpiration rate were appeared bimodal variability in one day,otherwise,Regulated Deficit Irrigation reduced the photosynthetic rate,but 80%CK treatment improved the water utilization effective rate at noon.Expansion-coloring period helped to improve SPAD value by irrigation 3 times,meanwhile,respectively,which could greatly increase the net photosynthetic rate,transpiration rate and water utilization effectively,after 50 d of anthesis,the MDA,Pro and soluble sugar content showed a significant increase trend.Setting-expansion period irrigated 3 times and expansion-coloring period irrigated 4 times,which could significantly reduce the content of soluble protein and raise the CAT activity.(3)Effects of Regulated Deficit Irrigation on soil physical and chemical properties in vineyard:Followed the change of depth deepening soil moisture performed the tendency to increase first and then decrease,soil moisture changed relatively stable of 80%CK treatment,which could significantly increased the root activity of 20-40 cm,irrigation 3 times in expansion-coloring period helped to improve root activity by 12.42%compared to 80%CK treatment.In addition,respectively,80%CK treatment increased the activity of urease,alkaline phosphatase and invertase.At the same time,the correlation coefficient matrix showed that root activity,invertase activity and catalase activity were significantly positive correlation,soil water content and root activity also appeared significantly positive correlation.(4)Effects of Regulated Deficit Irrigation on yield and quality of wine grape:80%CK treatment respectively increased the soluble solids,content of reduced sugar and total phenol,as well as reduced the titratable acid content,anthocyanins content was the highest under 70%CK treatment,CK and 50%CK treatment significantly improved the tannin content.Compared with 80%CK treatment,respectively,expansion-coloring period 3 irrigation increased soluble solids content by 2.95%,reduced sugar content increased by 0.91%,anthocyanins increased by 2.63%,and kept the tannin in the reasonable range.In addition,proper regulated deficit irrigation of expansion-coloring period contributed to increase the ear length and reduce the particle size,slightly reduced the yield.(5)Effects of Regulated Deficit Irrigation on wine quality:Regulated Deficit Irrigation had little impact on wine pH,alcohol and residual sugar performed the tendency to increase first and then decrease with the increased of Regulated Deficit Irrigation degree,while,dry extract is inversely proportional to the alcohol,80%CK increased the content of chromaticity.After first fermentation,80%CK significantly increased content of anthocyanins,and significantly reduced the tannin content after second fermentation,but the total phenol content was the highest increased by 28.74%compared to the CK.The critical growth period of Regulated Deficit Irrigation could increased content of anthocyanins,while,expansion-coloring period 3 irrigation increased total phenol by 6.42%.By establishing the correlation coefficient matrix,it is concluded that pH showed a significant negative correlation with the total acid,correlation coefficient reached 0.95,dry extract showed a significant negative correlation with the residual sugar,furthermore,chromaticity and total phenol,anthocyanins,respectively appeared very significant positive correlation,the correlation coefficient were 0.92,0.93.Based on principal component analysis comprehensive evaluation obtained that wine has a highest score under 80aCK treatment,namely highest-quality.