Effects Of Regulated Deficit Irrigation On Quality Of Carbernet Sauvignon Grape Berries And Wines

Ningxia Helan mountain is an important wine producing area in china,with special geographical location,scanty water resource,incomplete vineyard irrigation system.This research conducted the regulated deficit irrigation(RDI)experiment,adopted Vitis vinifera Cabernet Sauvignon as the experimental material and proceeded in chateau Lilan of Ningxia Helan mountain in 2015 and 2016 respectively to solving these problems,there were 4 treatment groups:RDI-1,RDI-2,RDI-3 and CK,the total irrigation amount of each group were 60%(Severe RDI),70%(Moderate RDI),80%(Mild RDI)and 95%(CK)of average crop evapotranspiration(ETc)of the past thirty years from april to september respectively.Determined the effect of RDI on development,phenolic compounds,anthocyanin compounds and aroma compounds of grapes,and made wines with the matured grapes by same brewing technology,determined the effect of RDI on the phenolic compounds,free phenols,anthocyanin compounds,aroma compounds and sensory quality of wines.In order to achieve the aims of saving water resources and production cost,improving the comprehensive quality of grape berries and wines,providing some theoretical basis for the optimization of the irrigation system of cabernet sauvignon in ningxia area.The results of research are as follows:(1)RDI in fruit enlargement period for the grapes has greater effects on the size of grapes,while lower the grain weight before the grapes got fully maturity,when grapes got fully mturity,RDI significantly reduced traverse diameter of the grapes while had no significan effect on longitudinal diameter and weight of grapes.RDI significantly increased reducing sugar and soluble solid content,while decreased the total acid content of grapes,when grapes got fully maturity in 2015 and 2016,the maximum increase of reducing sugar content was 11.49%and 4.73%,the maximum decrease of total acid content was 25.67%and 18.01%.(2)RDI improved total phenolic,total anthocyanin and flavonoids content of grapes in 2015 and 2016,and reached the highest content in RDI-1 treatment group,There were some effects of RDI on the total flavonol content of grapes,but the effects were not significant compared to the control;RDI improved the total tanin content of grapes in 2015,the total tanin content of grapes in RDI-3 group has been increased by13.23%than control,while the total tanin of grapes in 2016 between RDI groups and CK had no significant difference.Effects of RDI on total phenolic,tota anthocyanin and total flavonoids content of wines were similar to the grapes,the three compounds content of wines reached to the highest in RDI-1 group;RDI decreased the total flavonoids and tannin content of wines,but the effects were not significant compared to the control.(3)RDI improved 9 kinds of anthocyanins indican monomer content,and showed the similar effect on the total anthocyanin,malvidin-3-glucoside and malvidin-3-acetly-glucoside with the highest percentages of total amount of anthocyanins indican monomer content reached the highest content in RDI-1 group.RDI had no significant effects on the flavonoids kinds of free phenols of wines,while significantly improved non-flavonoids free phenols content,the maximum increase of wines in 2015 and 2016was 33.04%and 49.77%respectively.(4)The amino acid content reached to the highest in RDI-3 group,the fatty acid content reached to the highest in RDI-1.RDI significantly improved aroma content of grapes,the aroma compounds derivative from amino acid of grapes reached highest in RDI-3 group expect of ketone compounds,the aroma compounds derivative from fatty acid of grapes;The total aroma compounds content of grapes reached highest in the RDI-2 group,the increase than control was 35.47%and 56.49%in 2015 and 2016respectively,the total aroma compounds content of wines between RDI groups and the control had no significant difference.(5)The result of principal component analysis showed that RDI improved the comprehensive quality of grapes,the comprehensive quality of grapes ranked from high to low is RDI-1、RDI-2、RDI-3、CK both in 2015 and 2016.Quantitative descriptive analysis showed that RDI-2 treatment improve the aroma quality best in 2015 while RDI-1 treatment improve the aroma quality best in 2015,and the RDI-1 treatment had a great improvement than control for the global evaluation of wines in 2016.In conclusion,the RDI-1 treatment was determined as the optimization irrigation program,this program saved irrigation amount about 1650 m~3/ha and 1535 m~3/ha in2015 and 2016 respectively.