Effect On Processing Tomato Seedling Physiological Under Salt, Drought Stress And Study On The Screening Of Salt,Drought Tolerance Index

Xinjiang is located in inland arid area, water resources shortage, salinization is unfavorable factorswhich restrict the yield and quality of processing tomato.The effect of salt stress and drought stresssimulated by NaCl and PEG-6000on processing tomato seed germination and seedling growth werestudied on morphological, physiological, biochemical basis to further clarify the mechanism of droughtresistance and salt tolerance, to establish method system for drought resistance and salt tolerance ofprocessing tomato seed germination and seedling，to screening of drought and salt resistant materials.1. Processing tomato seed germination test under NaCl stress was done to determine morphologicalparameters. The results showed that salt stress has an obvious inhibitory effect on processing tomato seedgermination, the seed germination of seven processing tomato materials was differently inhibited by thestress. The salt tolerance of KT-16was better, but the salt tolerance of KT-63appeared worse. Germinationrate, germination energy, germination index, vitality index, root fresh weight, root dry weight, hypocotyldamage rate, can serve as indicators to appraise salt tolerance of processing tomato materials in sprout stagecomprehensively.2. Processing tomato seed germination test under drought stress simulated by PEG-6000was doneto determine morphological parameters. The results showed that drought resistance has an obviousinhibitory effect on processing tomato seed germination, and with the increase of drought resistance, thesorout index of drought resisting, the germination rate, germination potential etc. decrease gradually. Thechange tendencies of different drought resistance among difference provenance were similar, but the rangeof changes was different remarkably. The drought resistance of KT-16was better, but the drought resistanceof KT-70appeared worse.3. Processing tomato seedling test under NaCl stress was done to determine physiological,biochemical parameters. The results showed that the sequence of salt tolerance of7processing tomatoesfrom strong to weak was: KT-55> KT-25> KT-63> KT-16> KT-40> KT-18> KT-70, and the root dry weight,MDA, POD were important in salt tolerance; The salt tolerance optimal prediction equation of7materials:D=－0.129+0.004X1+0.002X2－0.001X3, the X1, X2, X3respectively represent the salt tolerancecoefficient of the root dry weight, MDA and POD.4. Processing tomato seedling test under drought stress simulated by PEG-6000was done todetermine physiological, biochemical parameters. The results showed that the sequence of droughtresistance of7processing tomatoes from strong to weak was: KT-55> KT-70> KT-63> KT-16> KT-40>KT-18>KT-25, and the CAT activity were important in drought resistance; The drought resistance optimalprediction equation of7materials: D=0.353+0.002X1, the X1respectively represent the drought resistancecoefficient of the CAT activity.