Effects Of Water Stress On Growth,Physiology And Quality Of Cabernet Sauvignon Grape

3 years of Cabernet Sauvignon was used as material in the experiment, and three treatments with different water stresses were set based on the pre-dawn leaf basic water potential (ψb). The three treatments were light drough(T3), middle drought(T2), severe drought(Ti)and no-water stress (CK) as a comparison. The regularations of water requiring and effects of different Water stresses on growing of Physiology and quality of Cabernet Sauvignon were explored. The results showed that:1.From April 5,2015(budding) until September20 (harvest),it had been taken 163 days and irrigated 624.68L in the whole growth stages totally.among these,from budding to flowering 147.6L per plant were consumed, from flowering to seting,23.31L per plant were needed, during Berry Expansion Period,provided 233.31L per plant,and from Veraison to Grape maturity,220.46L per plant were demended.With increasing degree of stress increased,water stress could be enhanced water saturation deficit and bound water content significantly, and decrese the content of leaf relative water.total water,free water and Free water/bound water at the same time.2.Water stress could be reduced to Photosynthetic pigments content gradually.and with increased levels of stress, the decrease is greater;Water stress also reduced net photosynthetic rate(Pn),transpiration rate (Tr)and stomatal conductance(Gs) of Cabernet Sauvignon,Promoted intercellular CO2 (G) concentration to appear to fall after rising,but to some extent, increased water using efficiency;With the increased levels of stress,Chlorophyll fluorescence of Cabernet Sauvignon, including, minimal fluorescence(Fo) shows a downward trend after rising, Maximum fluorescence (Fm), Variable fluorescence(Fv), the ratio of the variable to maximum fluorescence (Fv/Fm), the ratio of the variable to minimal fluorescence (Fv/Fo),sum of photochemistry quantum(Yield)and the rate of light electron transfer(ETR)and the photochemical quenching coefficient (qP)were decreased notably, while non-photochemical quenching coefficient(qN)increased remarkably,with more strong water stress.3.Water stress improved the content of Proline,and Soluble sugar of Cabernet Sauvignon, It also could be resulted in an upward trend after the early fall of Soluble protein,and declined the rate of MDA accumulation, CAT activity could be significantly improved by water stress, and POD activity presented a parabolic variation, SOD activity appeared to be the bimodal variation trend, which was more remarkable by the deepening of the stress degree.4.Water stress can promote the berry quality improvement, While severe stress is not conduced to form berry quality of Cabernet Sauvignon, light drought stress (T3) not only saved water by 28.37 percent, but also promoted the increase of soluble solids by 3.23 percent, berry maturity by 6.66 percent, the reduction of the total acid by 2.97 percent, the enhancement of anthocyanin content by22.58 percent, the increase of tannin by 29.70 percent and the advance of total phenols by 15.13 percent. Moveover,it also increased by 7.2 percent of yield per plant.