Study On Seed Germination And Seedling Of Three Species Of Roegneria Tolerated Salt-sensitivity

The paper studied on salt-sensitivity of seed germination and seedling of R.turczaninovii(Drob) Nevski var.macrathera Ohwi,R.stricta Keng f.stricta and R.komarovii(Nevski) Nevski,The results were as follows:1.The seed germination capacity of three species of Roegneria was promoted slightly When NaCl density was 75mmol/L.The germination rate,germination viability and germination index were reduced(p＜0.01) as the rising of NaCl density.Therefore,the germination was inhibited with high salt density.2.There has small effects on stem length,root length,root quantity,leaf length,leaf width,aerial parts fresh weight and dry weight and underground portion fresh weight and dry weight of three species of Roegneria When the NaCl density was 30mmol/L.But,the three species of Roegneria biology indexes were reduced(p＜0.01) as the rising of NaCl density.Therefore,high salt density inhibited the seedling growth.3.The physiology indexes of three species of Roegneria showed same tendency under the different concentration of NaCl stress.When NaCl density was 30mmol/L,only MDA had significant difference, others had no obvious difference.Along with the NaCl concentration increased,physiology indexes of three species of Roegneria compared with the contrast achieved extremely remarkable level(p＜0.01),the MDA,the Cell Membrane Penetrability,Pro and Ss had a positive correlation with NaCl density,Ch1 and RWC had a negative correlation with NaCl density.4.There has different effects on seedling biochemical indexes between three species of Roegneria under the salt stress.SOD,POD and CAT showd different change curves.The curves of SOD,POD increasd before then decreasd,the curve of CAT increased as the rising of NaCl density,and had a positive correlation with NaCl density.5.Generalized analysis all indexes of Roegneria seed germination,seedling biology,physiological and biochemistry.The results indicated:R.komarovii(Nevski) Nevski is salt tolerance plant,R.turczaninovii (Drob) Nevski var.macrathera Ohwi is saltsensitive plant,the salt adaptability of R.stricta Keng f.stricta is between the two plants.6.Selected four closely indexes related to the seedling salt-tolerant of three species of Roegneria, there are Leaf length,SOD,Ss and CAT.