Regeneration Plantlet For Elaeagnus Angustifolia L., Haloxylon Ammodendron And Atriplex Canescens (Pursh) Nutt. In Vitro And The Comparation Of Their Salt Tolerance

This study deals with in vitro rapid multiplication of halophytic Elaeagnus angustifolia L., Haloxylon ammodendron and American indigenous Atriplex canescens(Pursh)Nutt. Clonal types of the three trees were preliminarily established and tested-tube plantlets were acquired. The secondary tested-tube plantlets, when reaching a certain amount, were screened out by their salt resistance. NaCL was added into rooting media as stress factors and its concentrations were 0, 35mmol/L, 70mmol/L, 105mmol/L, 140mmol/L, 175mmol/L, 210mmol/L and 245mmol/L. during the time with salt stress, the rooting rate, multiples of germination, the time of salt damage, and symptoms of salt damage, percentage of salt damage and exponent of salt damage were recorded on a periodical base. When the tested-tube plantlets were under salt stress for 50d, the rooting rate, average rooting number, multiple of germination of lateral buds and growth coefficients were investigated. And the percentage of salt damage, exponent of damage, tissue humidity content, biological yield and exponent of stress sensitiveness were recorded. This study result will be foundational for introduction of landscaping halophytes, vegetative propagation of halophytes, breeding of asexual salt resistant clonal types and genetic improvement. The specific results of the study are following.1. The optimal culture conditions of Elaeagnus angustifolia L. were established by orthogonal tests and single factor tests as follows:①explants: the cotyledon of 10 days old seedling;②Efficiency differentiation induction media:MS+0.5 mg·L^-1NAA+ 2.0mg·L^-1BA+ 3%sucrose;③Efficiency seedling induction media: MS+0.1mg·L^-1NAA+ 1.0mg·L^-1BA+ 3%sucrose;④Robust seedling media: MS+0.1 mg·L^-1NAA+1.0mg·L^-1BA+0.2 mg·L^-1GA3+ 3%sucrose;⑤Rooting media: 1/2MS+1.0 mg·L^-1ABT1.0 mg·L^-1 +1.5%sucrose2. The optimal culture conditions of Atriplex canescens were established by orthogonal tests and single factor tests as follows: One year old strong half lignified buding stems were used as materials.A minimum media for initial culture:MS or modifed MS+BA1.0...