松嫩草地不同成熟度羊草种子对土壤埋深的生态响应

Ecological Responses of Different Maturity Leymus chinensis Seeds to Soil Burial Depths in Songnen Grassland

羊草(Leymus chinensis)是多年生根茎型禾草,也是东北松嫩盐碱化草地上的建群植物,针对不同成熟度羊草种子生态适应性在国内外未被涉及的现状,设置3种埋种深度(1,2,3 cm)以明确不同成熟度(盛花期后24,29,34,39 d)羊草种子对土壤埋深的生态响应。结果表明:不同成熟度的羊草种子同样表现出不同的出土成苗能力,盛花期后39 d的羊草种子活力最大,出苗率、出苗时间、叶片与根长度以及生物量等指标均优于其余3个发育时期的种子。埋种深度也显著影响羊草种子出苗能力,由于千粒重较小,羊草种子适宜浅播,1 cm是其最适宜的播种深度,此时种子成苗的各项指标最优。研究结果可以为羊草种子的发育生理学以及生产实践中播种技术优化等提供一定的科学依据。

Leyrnus chinensis （Trin.） Tzvel. is a perennial rhizomatous species of Poaceae, which is also the dominant grass species in Songnen salt-alkali grassland of Northern China. Due to the fact that no informa tion existed concerning the ecological responses of different maturity Leyrnus chinensis seeds, three kinds of buried depth （1 cm, 2 cm and 3 cm） were set in order to make clear the ecological responses of different maturity （24, 29, 34 and 39 days after peak anthesis） Leymus chinensis seeds in soil. Results showed that the response of Leymus chinensis seeds to burial depth was also greatly differed from different maturity times. Seeds after peak anthesis for 39 days had the highest vigor and best quality. The seedling emergence rate, seedling emergence time, seedling and root heights of seeds in this maturity time were superior to other three maturity times. In addition, buried depth also significantly affected the ability of seedling e mergence. Leymus chinensis seeds were suitable for shallow sowing due to the small thousand seed weight, and 1 cm was the most suitable planting depth. These results provide a scientific basis for seed de-velopment science and planting technology