Effects Of Salt Stress On Growth And Physiological Characteristics Of The Two Grape Cultivars

Objective:In order to research the effect of salt stress on growth and physiological indices of two cultivars ‘Huozhouheiyu’and ‘Huozhouhongyu’.salt tolerance of two grape cultivars were compared and provided a theoretical basis for the production practices.Method:The two-year cutting seedlings of ‘Huozhouheiyu and ‘Huozhouhongyu’ cultured in hydroponic were used as experimental material.Two cultivars were treated with three different concentrations of Na Cl(2g/L,3g/L,4g/L),then equal amount was applied by three times.Stem diameter,plant height,free water,bound water,relative conductivity,MDA content,soluble sugar content,proline content,protein content SOD activity,POD activity and CAT activity were measured on the day before treatment and on the 4,8,12 day after Na Cl treatment.Then chlorophyll content,chlorophyll fluorescence parameters and gas exchange parameters were determined on the 12 day after treatment.Results:(1)With Na Cl concentration increasing,plant height,stem diameter,free water and free water/bound water of two cultivars decreased.Bound water,relative conductivity,soluble sugar content,protein content,proline content and MDA content of two cultivars increased.SOD activity,POD activity and CAT activity of two cultivars firstly increased and then decreased.With stress time extending,plant height,stem diameter,free water and free water/bound water of ‘Huozhouheiyu’ were significantly lower than control treatment on the8 th day and 12 th day after the Na Cl stresses of 3g/L-4g/L.Bound water,relative conductivity,MDA content,soluble sugar content,proline content and protein content of ‘Huozhouheiyu’were significantly higher than control treatment on 8th day and 12 th day after the Na Cl stresses of 3g/L-4g/L.Plant height,stem diameter,free water and free water/bound water of‘Huozhouhongyu’ were significantly lower than control treatment in all stress time.Other indices of ‘Huozhouhongyu’ were significantly higher than control treatment in all stress time.SOD activity,POD activity and CAT activity values of two cultivars reached the maximum value on the 8th day after Na Cl stress of 3g/L.(2)The Na Cl stress increasing for 12 th day,Chla,Chlb and Chl(a+b)of two cultivars increased and Chla/b of two cultivars decreased.Chla,Chlb,Chl(a+b)and Chla/b of‘Huozhouhongyu’ had significant difference in the 3g/L treatment and the 4g/L treatment than control treatment.The minimal fluorescence(Fo)and Intercellular CO2 concentration(Ci)of two cultivars increased.The maximal fluorescence(Fm),actual photochemical efficiency of photosystem Ⅱ(PSⅡ)(ФPSⅡ),maximum photochemical efficiency of photosystem Ⅱ(PSⅡ)(Fv/Fm),net photosynthetic rate(Pn),stomatic conductance(Gs),transpiration rate(Tr)oftwo cultivars decreased.There was a significant difference in 3g/L treatment and 4g/L treatment than control treatment.Conclusion:On the 12 th day after NaCl stress,there was a siginificant difference in growth and physiological indices of two cultivars between the 3g/L-4g/L treatment and control treatment.‘Huozhouhongyu’ was affected more seriously than ‘Huozhouheiyu’ by salt stress.