181份多样性籼稻种质苗期和成熟期镉积累表型评价

Phenotype Evaluation of Cd Accumulation of 181 Diverse Indica Germplasm at Seedling and Mature Stages

近年来,中国稻米镉污染问题较为严重,对人们生活和健康带来严重的威胁。选育低镉积累水稻品种是解决此问题最简单有效的途径,而筛选低镉积累水稻资源是低镉积累水稻品种选育的前提和基础。本研究以引进的来自31个国家(地区)的181份多样性丰富的籼稻种质为研究材料,利用水培和中度镉污染的农田分别对这些种质的苗期地上部分镉吸收和成熟期稻米镉积累进行测定。研究结果表明,苗期地上部分和成熟期稻米镉积累量在品种间有很大差异。苗期地上部分镉含量变异范围为9.90~106.80 mg/kg,而稻米镉含量的变异范围为0.12~1.23 mg/kg。鉴定出稻米镉含量低于0.20 mg/kg的种质3份,地上部和稻米镉含量均较高的种质16份。相关性分析结果表明,苗期镉吸收与稻米镉积累极显著相关(r=0.3861, p<0.000 1),苗期镉吸收低的稻种,其稻米镉含量亦相对较低,苗期镉吸收可作为稻米镉累积的重要指示之一。本研究结果为籼稻低镉积累品种选育和镉污染农田的植物修复提供良好的材料基础。

Cadmium pollution（Cd） in rice is a severe problem in China, and becoming a serious threat to human life and health. Breeding low Cd accumulation rice varieties is a simple and effective way to solve this problem.Screening and selecting low Cd accumulation rice resource is the premise and basis for low Cd accumulation rice varieties breeding. In the present study, a diverse Indica germplasm which contained 181 Indica accessions origi nated from 31 countries（regions）, was used as materials. And we measured the cadmium absorption in aboveground parts of these germplasm in seedling stage and grain Cd accumulation, utilizing hydroponics and the field moderately polluted by cadmium. The results indicated the Cd accumulation varied greatly both in seedling and in grain. The Cd concentration in seedling range from 9.90-106.80 mg/kg, and range 0.12-1.23 mg/kg in grain. We identified that the Cd concentration of 3 accessions lower than 0.20 mg/kg in grain. 16 accessions were identified to be high Cd accumulation both in seedling and in grain. Results from correlation analysis indicated that the Cd absorption in seedling and the Cd accumulation of grain was closely related（r=0.3861, p0.000 1）, which mean the rice seed with low Cd absorption in seedling tend to have low Cd content in grain. The absorption Cd could be used as one of the standard for the Cd accumulation in rice. This study might be provide a material foundation for breeding low Cd accumulation varieties, and also for for the phytoremediation of the field with cadmium pollution.