3种禾本科牧草种子萌发及生理对高寒昼夜变温的适应性研究

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中图分类号：S543 文献标识码：A 文章编号：1007-0435（2026）01-0266-09

Abstract：This study investigated the temperature adaptability of three grass species （Elymus nutans，Bromus inermis，and Festuca sinensis） through the controlled experiments simulating diurnal thermal regimes （ 10∘C/ 5∘C ， 15∘C/5∘C ， 20∘C/5∘C ， 25∘C/10∘C ）characteristic of their natural habitat during March-November. We systematically analyzed seed germination dynamics（quantified by germination rate，potential，and index），seedling growth parameters，and physiological stress markers to elucidate species-adaptive responses to temperature gradients in Alpine region.With the increase of temperature，the germination rate，germination potential and germination index of the Elymu snutans seeds allincreased first and then decreased. The germination rate，germination potential and germination index of Bromus inermis and Festuca sinensis seeds increased significantly with the increase of temperature. The contents of malondialdehyde（MDA），soluble sugar （SS）and free proline（Pro）of the three grass seedlings increased with decreasing temperature.The results showed that the optimum temperature was 20∘C/5∘C for Elymus nutans， 25∘C/10∘C forBromus inermis and Festuca sinensis. The comprehensive evaluation of the membership function showed that the temperature adaptability of the three grass species was Elymu snutans > Bromus inermis > Festuca sinensis.

Key words：Temperature change;Elymus nutans; Bromus inermis;Festucas inensis;Seed germination; Physi ological characteristics

西藏是青藏高原的主要组成部分，平均海拔在4000m 以上，冬季时间长，昼夜温差大，冬季平均气温为一 3.9∘C ，极端最低气温达到 -46.4∘C ，全年低于 5∘C 的时间长达200d，大部分地区为高海拔低压缺氧地带，其被称为“世界屋脊”。（剩余17246字）