源于大麦F1小孢子氮胁迫培养自交一代的耐低氮性评价

为了探索快速改良大麦耐低氮性状的育种方法，以2份耐低氮亲本配制（正反交）杂交组合，游离其F₁代小孢子进行氮胁迫培养，获得85个加倍单倍体（Double haploid,DH）系。取其种子播种于正常供氮和降氮的土壤中，以亲本作对照，观察群体的形态特征表现，以此对耐低氮性进行初步的评价。同时，对耐低氮性明显超亲的基因重组体进行氮代谢相关的生理生化指标分析，以探讨其与有关农艺性状的相关关系。结果表明，（1）通过氮胁迫相关的形态特征鉴定，正反交DH系低氮胁迫响应的相对值优于亲本；（2）筛选到10份明显优于双亲的DH系，对其进行相关酶活力测定，发现在低氮胁迫下，谷氨酰胺合成酶（GS）活力相对值与成熟期单株产量存在极显著正相关性，可以初步作为成熟期氮素营养检测的生化指标。依据研究结果可以认为，运用杂交结合F₁小孢子氮胁迫培养方法，能够产生耐低氮性优于双亲的DH系。

Evaluation of Low Nitrogen Tolerance of Homozygous Population Derived from F1 Microspore Culture under Nitrogen Stress in Barley

In order to explore the new breeding technology for rapid improvement of low nitrogen tolerance in barley,using two genotypes with tolerance to low nitrogen as parents(reciprocal cross),the 85 double haploid(DH) lines derived from F₁ microspore culture with nitrogen stress were obtained. The population were treated with two nitrogen levels. Compared to the parents,the morphological feature responses of DH lines to nitrogen stress were investigated. The results showed that the responses to low nitrogen relative values of DH lines were better than those of the parents.10 DH lines which are significantly better than their parents were screened and the activity of related enzymes are determined. Under low nitrogen stress,relative value of glutamine synthetase activity(GS) is highly correlated with grain yield per plant at mature stage. It is suggested that the method of F₁ microspore culture technology with nitrogen stress could produce a better gene recombination,which is tolerant to low nitrogen,in homozygous population than that in parents.