Effects of temperature, PEG and NaCl treatments on seed germination and seedling growth of three Lespedeza species

The seed germination percentage, germination index, radical length and seedling length of Lespedeza davurica cv. Longdong, L. hedysaroides cv. Keerqin and L. potanimii were measured under treatments with temperature, PEG and NaCl stress. The results showed that 20/30 ℃ was the most suitable temperature for the three Lespedeza species. PEG stress had great influence on seed germination index and seedling length. L. davurica cv. Longdong and L. potanimii had the better performance under drought tolerance stress. The germination index, radical length and seedling length of these three species seeds significantly decreasing under NaCl stress treatment. L. potanimii showed the best performance under NaCl stress treatment. L. potanimii Vass. was selected as the best accession with drought and salt stress tolerance by comprehensive evaluation, which will provide the insight for germplasm cultivation and genetic breeding for new varieties.