Study On Relationship Between Anatomical Structure Characters, Important Component Of Puccinellia Tenuiflora And Its Salt Tolerance

Soil salinity is one of the main abiotic stresses that restrict the development of agriculture worldwide.How to improve crop salt tolerance and make good use of salinity-alkalinity soil has become a significant thesis urgent to be solved.Puccinellia tenuiflora is a natural salt tolerant plant widely distributed in the north of China,and it can grow well in the soil with high Na⁺ concentration and high pH.The excellelant salt and alkali tolerance of P.tenuiflora made it become the perfect material of the research on salt and alkali tolerance.Compared with NaC1 stress,the impact of NaHCO₃ stress with high pH on plant is more complex.In this paper,we choose P tenuiflora as experimental material and rice cultivar Nipponbare(Oryza sativa L.) as comparison.Using methods of micro and ultra-structure observation,2-D electrophoresis ect,not only seed germination,seedling growth character, stoma as well as leaf and root epidermis Character of P.tenuiflora were observed,but also the absorption and transportation Character of three important ion component K⁺,Na^<sup> and Ca²⁺ in P.tenuiflora,and the changes of protein expression of its root were studied in detail.The purpose is to reveal the salt tolerant base of P tenuiflora from three different aspects of microstructure,ion distribution and protein expression.The result has practically instructional significance on the understanding of salt tolerant character of P.tenuiflora.Moreover,study on protein level provides new clew to the understanding on response of P.tenuiflora to NaHCO₃, and it also lays vital foundation to the further study of these genes by genetic measures.Main results of the above research are as follows:1.Generally speaking,with the increasing of NaHCO₃ concentrate,the seed germination rates of P.tenuiflora decline.Although seedling height and dry weight of P.tenuiflora were not obviously affected by NaHCO₃ stress,those of Rice were restrained under the same stress.2.Length of P.tenuiflora stoma increase under short time of low concentrate NaHCO₃ stress,while it decrease under high concentrate of NaHCO₃;Width of P.tenuiflora stoma increase under high concentrate or long time of NaHCO₃ stress,and the effects of the two factors can be combined with each other.Length and width of rice stoma decrease obviously under low concentrate of NaHCO₃ stress;Density of stoma on P.tenuiflora leaf epidermis is 7 times that of Rice.3.There are wax layers on both P.tenuiflora and rice.Density of wax layers enhances with the increasing of NaHCO₃ concentrate and stress time length,the increasing extent follows the order of P.tenuiflora＞rice;There are secretion on P tenuiflora leaf epidermis, and the amount of secretion increased with the increasing of NaHCO₃ concentrate and stress time length.Salt crystal can be excluded by P.tenuiflora leaf epidermis under high concentrate of NaHCO₃ stress,while no salt crystal of secretion can be found on the leaf epidermis of rice. Lateral roots and secretion can be found on both P.tenuiflora and rice root epidermis,and the numbers of lateral roots follows the order of P.tenuiflora＞rice;Lateral roots become thinner after long time of high concentrate NaHCO₃ stress.With the increasing of NaHCO₃ concentrate and stress time length,the amount of secretion on P.tenuiflora root epidermis increases,while that of rice doesnot show any changes.4.Na⁺,K⁺ and Ca²⁺ content in roots and shoots of P.tenuiflora seedlings were determined after NaHCO₃ stress.The result shows that the ability of two kind of K⁺ absorption system of P.tenuiflora is both higher than rice,so does the K⁺/Na⁺ of P.tenuiflora roots;With the increasing of Na⁺ concentrate,P.tenuiflora shows higher Ca²⁺ absorption and transportation ability than rice.5.Roots protein of P.tenuiflora plates under 150mmol/L concentrate of NaHCO₃ and NaC1 stress was compared with distilled water in order to find the reason why NaHCO₃ and NaC1 stress showed different harm effect on plant.The results are as follows,among about 400 protein spots,there are 13 spots increased in abundance after NaHCO₃ stress,3 spots only appear under NaHCO₃ stress.3 stress correlative proteins were obtained by MS analysis,they are F3H,CYP450 and fructose-bisphosphate aldolase.