Effects of stratification in the winter on the seed germination characteristics of 5 alpine meadow plant species

In order to clarify the effects of the winter stratification on seed germination of alpine meadow plants, we studied the seed germination characteristics of 5 kinds of alpine meadow plants which were stratificated in Tianzhu alpine meadow soil, Tibetan sheep dung and yak dung, respectively, with the seeds stored indoor as the control. The results showed that the stratification influenced the germination percentage, initial germination days and germination index of Kobresia humilis, Blysmus sinocompressus, Iris tenuifolia, Carex enervis and K. capillifolia seeds which varied with the integrity of the seed coat, stratification matrix and grass species. Compared with the control, the winter stratification improved the scarified seed germination percentage and the germination index and reduced initial germination days of K. humilis, B. sinocompressus, I. tenuifolia, C. enervis and K. capillifolia. The influence of winter stratification on the seed germination of complete seed was lower than that on the scarified seed. The germination percentage of the scarified seed of B. sinocompressus stratificated in yak dung was significantly higher (P<0.05) than that in the Tibetan sheep dung and soil treatment. For the germination of the scarified seeds of K. humilis, I. tenuifolia and C. enervis, there was no significant difference between the different treatments of stratification matrix. There was no significant effect of winter stratification on the germination of the complete and the scarified seed of K. capillifolia.