不同倍性新麦草种子萌发特性的研究

Study on Seed Germination Characteristics of Pasthyrostachys juncea with Different Ploidy

与二倍体新麦草相比,染色体加倍后的四倍体新麦草的种苗生活力强,种子营养成分含量高,对低温、干旱等极端环境的适应能力强。对染色体加倍选育出的四倍体新麦草种子与正常的二倍体种子的萌发指标,幼苗芽长、根长、芽根比,以及种子萌发过程中淀粉酶活性和可溶性糖含量的变化进行了比较研究表明:四倍体新麦草种子在千粒重、发芽率、发芽势、活力指数和发芽指数等方面均显著高于二倍体种子(p<0.01);染色体加倍能促进幼苗芽和根的生长,但对幼苗芽的促进作用更强;与二倍体新麦草种子相比,四倍体种子萌发过程中淀粉酶的活性更强,糖代谢速度快,更多的可溶性糖能给幼苗生长提供能量。

Compared with diploidy,the seedlings of Pasthyrostachys juncea with tetraploidy have stronger viability, higher nutrient contents and better tolerance of lower temperature, drought and other extremely environments. This experiment is about the germination characteristics of two varieties of Russian wildrye with diploidy and tetraploidy. We compare their germination indicators which include bud length, root length, ratio of bud and the changes of amylase activity and soluble sugar content. The results showed that, tetraploid seeds are significantly higher than diploid seeds in the terms of 1 000-grain weight, germination rate, the germination energy, index of germinated and vigor（ p 〈 0.01 ）. Doubled chromosome can promote the growth of seedlings and roots, and especially has a stronger effect on seedling growth. Tetraploid seed had stronger amylase activity, rapid glucose metabolism, therefore much more soluble sugar provided energy for the necessary germination.