Studies On Saline-alkaline Tolerance Of Different Grape Scion-stock Combinations

Red Globe/Beta one-year old seedlings were treated with neutral salt and alkaline salt tostudy the tolerance of grapevines to different salt and alkali ions. At the same time, fiveChardonnay/rootstocks （1103P, SO4,5BB,3309C,101-14MG） combinations were tested toinvestigate the effects of complex saline-alkali stress to the conditions of leaves being harmedand physiological, biochemical indicators. Besides, the salinization resistance of differentkinds of scion combinations was preliminarily evaluated. The results were as follows:1. The growth of shoots in Red Globe/Beta plants was severely inhibitedunder85mmol/L NaHCO₃alkaline salt stress, and the hazards were aggravated with theprolonging stress days; the leaves were etiolated, fallen off and the plants died in the laterstage. While the Red Globe/Beta plants were still able to maintain normal growth at thesame concentration of neutral salt （85mmol/L NaCl,85mmol/L Na₂SO₄） stress. The rootactivity and root respiration of Red Globe/Beta were significantly reduced under alkalinestress, whereas neutral salt stress only significantly reduced root activity, and it had nosignificant effects on root respiration.2. The chlorophyll contents were significantly reduced under NaCl and NaHCO₃stress;meanwhile, the net photosynthetic rate （Pn） and chlorophyll fluorescence parameters Fv/Fm,Fv/Fo, PI_ABSwere significantly lower than that of control, and the reductions were more underNaHCO₃stress. The relative conductivity of leaves and roots increased under salt and alkalistress, and the membrane permeability of alkali-stress roots increased greater than the othertreatments. The soluble protein and MDA content of leaves increased along with the treatmenttime, the increasing proportion under alkaline salt stress was larger than the ones underneutral salt （NaCl, Na₂SO₄） stress, and it was larger under the Cl^-stress than the one underSO42-stress. The SOD activity under alkaline stress was significantly lower than the controland other treatments, while the activity under NaCl treatment was higher than Na₂SO₄.3. The total Na⁺content of Red Globe/Beta plants increased significantly under salt andalkali stress. The Na⁺content of leaves under NaCl stress increased significantly, but underNaHCO₃stress, only the content of shoots and roots increased significantly. The total K＋content of plants and K/Na of leaves under salt and alkali stress were lower than the control, and NaCl stress had much more effects than NaHCO₃. The Fe²⁺and Ca²⁺contents inshoots and leaves were significantly reduced under alkaline stress. It was concluded thatNaHCO₃stress caused serious damages to grapevines, while Na₂SO₄cause less damage; RedGlobe/Beta had stronger tolerance to NaCl than NaHCO₃.4. The chlorophyll content and root activity of Chardonnay/rootstocks combinationsshowed a first increase and then decrease along with the treatment time undercomposite saline-alkali stress, the symptoms of salt injury appeared in the middle term,etiolated leaves appeared from lower parts. The net photosynthetic rate （Pn） wassignificantly decreased with the increase of stress concentrations and along with the treatmenttime; quite differences among different scion/rootstock combinations was observed in the lowconcentration （0.27%） treatments, but little differences under high concentrations （0.54%）stress was obseved. The chlorophyll fluorescence parameters Fo increased, while Fv, Fm,Fv/Fm, PI and Fv/Fo were significantly lower than that of control. The electrolyte leakagerate of leaves and roots were gradually increasing along with the treatment time, and thedifferences of roots electrolyte leakage among combinations were significant. The solubleprotein, proline and MDA content were significantly increased under the high concentrationof composite saline-alkali stress, and the SOD activity was first increased and then decreasedalong with the treatment time.5. The Na⁺content in different organs of Chardonnay grafted plants undercomposite saline-alkali treatment increased significantly, and leaves accumulated most.Except Chardonnay/101-14MG, the total K+content and leaf K⁺content of othercombinations were higher than that of control, and the K/Na of different organs weresignificantly lower than control. The content and distribution of Fe²⁺were significantlyaffected, and the content in leaves and roots were significantly lower. Chardonnay grafted ondifferent rootstocks could tolerate low concentrations （0.27%） of compositesaline-alkali stress, but had a poor tolerance to high concentration （0.54%）. The sequence ofsaline-alkali tolerance was in order of Chardonnay/1103P> Chardonnay/SO4>Chardonnay/3309C> Chardonnay/5BB> Chardonnay/101-14MG.