Abstract
Alkali grass (Puccinellia tenuiflora) is an expected prominent plant to achieve crop production and phytoremediation in saline-alkaline environment because of its high tolerance to saline-alkali soil. However, little is known on its behavior during initial growth process under high pH conditions. In this work, we compared germination rates and initial growth under different pH conditions. The germination rates of alkali grass at pH 5.5, 8 and 10 were 6.7%, 10% and 20.7%, respectively. It was striking that the highest germination rate was obtained when the seeds were sawn at the highest pH condition. To observe initial growth, the length of seedlings transplanted and grown on media prepared at pH 5.5,8 and 10 were measured. The fasted growth was recorded on the medium of pH 10. Since acidification of the media by alkali grass was expected, we traced the pH of the media for 15 days. Alkali grass decreased the pH of the media to 5.73 during the first 5 days. After the fifth day, the pH increased slowly to 6.95. The results suggested that alkali grass expresses a high adaptation ability to alkali soil from germination, and remediates its rhizospare.
