关键词: 呼伦贝尔, 天然草地, 野生豆科牧草, 温度, 种子萌发

Abstract: The objective of this study was to investigate the germination characteristics of wild forage seeds in Hulun Buir natural grassland. Germination tests of three species of wild leguminous forage seeds, including Medicago ruthenica, Astragalus laxmannii and Trifolium lupinaster collected from different areas, were carried out under different temperature conditions （15 ℃, 20 ℃, 25 ℃ and 30 ℃）. The germination indicators of the selected forages were assessed and analyzed. The results showed that the seed germination rates of the three wild leguminous forages were generally low, and different temperatures had significant effects on germination of the seeds. The germination rate, germination energy, germination index and germination speed of Medicago ruthenica seeds and Trifolium lupinaster seeds were elevated with the increase of temperature, and the highest germination indicators were observed at 30 ℃; the germination rate, germination energy, germination index and germination speed of Astragalus laxmannii seeds were elevated at initial observation period and then reduced with the increase of temperature, and the highest germination indicators were found at 25 ℃. The highest seed vitality index （14.53） of Medicago ruthenica was observed at 20 ℃; the seed vitality index of Astragalus laxmannii ranged from 4.89 to 7.11 at different temperatures, and the highest value was found at 25 ℃; Trifolium lupinaster had the highest seed vitality index （18.04） at 30 ℃. Comprehensively, the suitable temperature for germination of the three species of wild leguminous forages was 25-30 ℃. The obtained results of this study provide a theoretical basis for improving germination rates of wild forage seeds in Hulun Buir natural grassland.

Key words: Hulun Buir, natural grassland, wild leguminous forage, temperature, seed germination