Effects of Different Soil pH and Soil Extracts on the Germination and Seedling Growth of Leymus chinensis
不同pH 值土壤及其浸提液对羊草种子萌发和幼苗生长的影响

We investigated the effect of soils with different pH and soil extracts of nonsaline-alkali soil and saline-alkali soil on the germination and seedling growth of Leymus chinensis. Soils with different pH values were obtained by mixing the nonsalinealkali soil and saline-alkali soil at different ratios and adjusting the saline-alkali soil with sulfuric acid. For the mixed soil, the proportion germination in the substrate with pH values from 7.49 to 9.14 was higher than 50%, and the seedlings could grow normally. When the pH value was higher than 9.53, the proportion germination was lower than 50% and only some of the seedlings could grow normally; when the pH value was higher than 9.86, all the seedlings died within 50 d after sowing. After adjustment with sulfuric acid, seed germination rates were significantly improved; seedlings grew well in the saline-alkali soil and better with pH values between 7.5 and 9.5. Seeds of L. chinensis germinated best with pH between 8.0 and 8.5. Different concentrations of the extracts of the nonsaline-alkali soil could improve the germination to some extent, and a ratio of soil to water of 1:1 resulted in a significantly higher germination rate as compared with the control. However, treatments of the saline-alkali soil extracts and the control did not produce different germination rates.