全球水稻分子育种计划亲本的深根特性鉴定

Characterization of Deep Rooting of the Parental Lines Used in the International Rice Molecular Breeding Program

干旱是当前水稻实现高产稳产所面临的重要限制因子之一,增强水稻深根系是提高水稻抗旱性的重要途径。以"全球水稻分子育种计划"中的177份优异种质为试验材料,利用改良的"篮子法"鉴定了55d秧龄时的株高、分蘖数、深根数、浅根数、总根数以及深根比,并分析了这些性状在群体中的分布特征。结果表明,这些农艺性状在群体中都呈正态分布,存在丰富的表型变异。水稻品种间的深根比差异较大,大部分属于浅根系材料,只有沈农265、Lemont、Yen Fang Chu和原粳7号4个材料的深根比超过了40%。对这些优异资源农艺性状的了解,为在节水抗旱稻育种中深入利用这些亲本及其构建的导入系群体提供理论依据。

Drought is one of the most serious abiotic stresses which limit yield potential in rice and developing a strong deep root system is an important strategy to meet the drought stress. In this study, a set of 177 rice germplasm which were used in the international molecular rice breeding program were evaluated for the traits related to root architecture using a modified ＂basket＂ method in the field. Six root growth related traits were evaluated, including plant height, tilller number per plant, shallow root number, deep root number, total root number and the ratio of deep root after the seeds were sown 55d. Normal distributions and wide variations were observed for all six root-related traits in the population. Most of the parental lines showed a shallow root architecture, only four cuhivars, Shennong 265, Lemont, Yen Fang Chu and Yuanjing 7 ,had a ratio of deep root more than 40%. This study provides information for breeders to choose these elite germplasm and their introgression lines in the breeding program for developing water-saving and drought-resistance rice varieties.