大豆抗镉和籽粒低积累的分子机理解析

土壤镉污染程度和面积日趋严重，从人类健康和农业可持续发展的角度，减少农作物籽粒中镉含量已是农业生产的重要任务，选育低吸收、籽粒低积累的作物品种为我们开辟一条降低镉危害的最经济可持续的线路，而通过解析作物籽粒低积累的遗传基础、理解分子机制才可达到改良籽粒低积累性状的目的。本项目以华夏3号（中抗、低积累）和中黄24（敏感、高积累）及其衍生的F6:7重组自交系群体为材料，首先利用新一代全基因组测序技术分析两亲本间差异位点，开发新标记；然后利用高通量基因表达技术分析两亲本间差异表达的基因（包括编码蛋白和非编码的小分子），开发新标记；再利用重组自交系群体对所开发的标记与镉抗性、籽粒积累数据进行连锁分析，寻找与大豆抗性、低积累的QTL；并对定位信息在育种材料中验证。整合表达谱和连锁分析的信息，理解大豆镉抗性和低积累的分子机制，为开展分子设计育种做准备。

Vast areas of agricultural soils are contaminated with Cadmium(Cd) through the use of super phosphate fertilizers and sewage sludge, and inputs from mining and smelting industries.From the viewpoint of our health and sustainnable agricultural production,minimizing Cd content in their grain is an urgent matter.Selection and breeding of crops for low uptake and accunulation in grain open up new opportunities to minimize Cd in the food chain.To achieve this goal,the genetic components controlling advantageous traits need to be identified to provide an understanding of their molecular mechanisms.In this project, firstly, the genome of two contrast genotypes, Zhonghuang24 (sensitivity, high Cd accumulation) and Huaxia3 (resistance，low Cd accumulation),will be resequenced by the high-throughput sequencing .The structure difference will be revealed through comparing the reads from two genotypes. Secondly, the transcriptome data of root, leaf and seed stressed Cd will be provided by RNA Seq-Atlas. Small RNAs and target genes will be uncovered by high-throughput sequencing. Thirdly, the new markers will be developed based on those information, and map QTLs associated with Cd resistance and low accumulation in soybean in the recombinant inbred line population(F6:7) derived from Zhonghuang24 / Huaxia3. Integrating expression profiling and linkage analysis, we understand the molecular regulating network of tolerance and low cadmium accumulation in soybean and establish the blueprints of molecular design breeding.