Elucidation of mechanism and development of appropriate technology for seed hardening in rainfed wheat farming in drylands

种子硬化是干旱旱地旱作农业中改善种子萌发和出苗率差的主要限制因素之一，是一种种子预处理技术。本文通过对旱地主要谷类作物小麦籽粒硬化效应的遗传差异、籽粒硬化机理及籽粒硬化对产量的影响进行了研究。结果表明，硬粒小麦和合成面包小麦的种子硬化对种子萌发和出苗的影响存在遗传差异，赤霉素和α -淀粉酶活性与种子硬化的影响有关。此外，在播后雨量充足的情况下，种子硬化不能提高籽粒产量，但不会降低籽粒产量。

Seed hardening is known as one of seed pretreatment techniques to improve poor seed germination and seedling emergence which are major limiting factors of crop grain yield in rainfed farming in drylands. In the present study, I investigated to elucidate the genetic differences for effects of seed hardening, the mechanism of seed hardening and the influence of seed hardening on grain yield in wheat which is major cereal crop in drylands. As the results, it was found that there are genetic differences for effects of seed hardening on seed germination and seedling emergence in durum and synthetic bread wheat, and gibberellin and alfa-amylase activity were concerned in the effects of seed hardening. In the condition of sufficient rainfall after sowing, in addition, it was found that seed hardening couldn't increase grain yield, but not decrease too.