小麦显性矮秆基因Rht3及其衍生系统抗穗萌特性研究  

Pre-harvest Sprouting Resistance of the Dominant Dwarfing Gene Rht3 and Its Derivative Lines in Wheat

作　　者：傅大雄[1] 阮仁武[1] 宗学凤[1] 胡奎[1] 张建奎[1] 戴秀梅[1] 

机构地区：[1]西南农业大学农学与生命科学学院,重庆400716

出　　处：《作物学报》2005年第4期401-407,共7页Acta Agronomica Sinica

基　　金：国家自然科学基金项目 :小麦显性矮秆基因复等位多态特性研究 (3 0 3 70 875 /C0 2 0 2 0 5 0 2 );重庆市小麦遗传资源创新工程项目资助

摘　　要：采用近等基因系法及成熟种子室内萌发试验研究了小麦显性矮秆基因Rht3及其衍生系统的抗穗萌特性,并对普通小麦13个显性、半显性、隐性矮秆基因的抗穗萌性能进行了评价。结果表明,Rht3基因及其株高提升的突变衍生系具有显著而稳定的抗穗萌特性。将Rht3基因回交导入不抗穗萌的普通小麦,受体品种成熟种子的α淀粉酶活性降低了6 8% ,浸润3d及6d的种子萌发率下降了5 4与6 0个百分点,抗穗萌性能提高2 .8与7.5倍,从而使不抗穗萌的品种变成了高抗穗萌的品系。此外,由Rht3基因制约的抗穗萌特性与普通小麦非Rht3基因制约的抗萌特性可以累加,通过杂交可以合成超亲遗传的强力抗萌遗传资源。矮秆基因资源抗穗萌性能评价的结果显示,Rht3是目前已知最抗穗萌的普通小麦矮秆基因,Rht12的抗性次之,Rht10、雨D、ⅡA、西南0 2等矮源具有较弱的抗性。已获得一批达到小麦矮化育种理想株高而又抗穗萌的Rht3血缘的突变衍生系,这将有利于突破Rht3基因植株过于矮化的缺点,最终将其作为矮秆与抗穗萌的基因资源应用于小麦育种。The methods of near isogenic lines and germination test of mature seeds in the laboratory were used to investigate the preharvest sprouting resistance of the dominant dwarfing gene of wheat, Rht3, and its derivative lines, and the pre-harvest sprouting resistance of 13 dominant, semi-dominant and recessive dwarfing genes of common wheat (Triticum aestivum) was evaluated. The results showed that Rht3 and its derivative lines with increased plant height possessed stable and significant resistance to pre-harvest sprouting. When Rht3 gene was introduced into a non-resistant cultivar of common wheat, the receptor cultivar showed a 68% decrease in α-amylase activity in its mature seeds, the germination percentage of the seeds soaked for 3 and 6 days dropped by 54% and 60% and their pre-harvest sprouting resistance improved by 2.8 and 7.5 times, respectively. Consequently, the non-resistant cultivar was changed into a highly resistant one. The results also demonstrated that there was an additive effect for the resistance to pre-harvest sprouting controlled by Rht3 and by non-Rht3 genes in common wheat and that hybridization between them could produce highly pre-harvest-sprouting resistant genetic resources with transgressive inheritance. Evaluation of pre-harvest-sprouting resistance in the dwarfing sources indicated that among the known dwarfing genes of common wheat, Rht3 was the only one controlling the highest resistance to pre-harvest sprouting, followed by Rht12, and other dwarfing sources, such as Rht10, Yu D, ⅡA and Xinan 02 controls lower resistance. A group of mutation-derived lines of wheat with Rht3 in their origin have been developed, whose plant height are enhanced to different extents and some may have a height close to the ideal plant height for wheat. These lines will help overcome the disadvantage of Rht3-carrying plants that they are too short in stature, and can be exploited as valuable genetic resources of dwarfism and pre-harvest sprouting resistance in wheat breeding.

关 键 词：小麦 显性矮秆基因 穗萌 Α-淀粉酶活性 矮化育种 

分 类 号：S512.1[农业科学—作物学]