云南软香型籼稻品种滇屯502的复壮研究

软香型品种滇屯502是云南特色优质米生产的当家品种,30余年生产应用种性退化严重,在无病虫害防治条件下,其稻瘟病发病率为100%,产量减少41.9%。为了对该品种进行复壮,采用单穗选择、株系比较、品系鉴定的方法,紧扣稻瘟病抗性、香味和软米几个重要而典型的性状,开展滇屯502复壮相关研究。结果表明,在2.67万株滇屯502群体中筛选出3个复壮品系,入选率为0.01%。这3个品系表型和食味品质与滇屯502相似,但产量和稻瘟病抗性较滇屯502分别至少提高41.1%和58.3%。利用复壮品系混系繁殖形成的复壮滇屯502,较原种滇屯502的生产力得到明显提高。本研究结果可为云南软香常规稻品种复壮提供技术和经验指导。

Rejuvenation of Soft and Aromatic indica Rice Variety Diantun502 in Yunnan

Soft and aromatic rice Diantun502 is a main variety for the production of special high-quality rice in Yunnan, which productivity has been severely degraded due to large-scale cultivation for more than 30 years. If there is no control of pests and diseases for the variety, the incidence of rice blast will be 100%, and the yield will be decreased by 41.9%. For the sustainable development of the industry, it is very important to conduct rejuvenation of the rice. In this study, its rejuvenation was carried out using the methods of single panicle selection, plants comparison and lines evaluation, which focused on several crucial and typical characters including rice blast resistance, fragrant and soft characters. The results showed that three lines were selected in 26 700 plants of the variety population with about 0.01% of the selection rate. In comparison with the original variety Diantun502, the selected lines had similar phenotype and taste quality, but their yield and rice blast resistance were increased by 41.1% and 58.3%, respectively. The production captivity of rejuvenation Diantun502 population, which was generated by blending propagation of the lines, was improved obviously. The results would be provided technology and experience references for soft and aromatic inbred rejuvenation in Yunnan.