基于根尖转录组的水稻深根性基因的挖掘

水稻是我国最重要的粮食作物,但是由于旱灾导致的粮食减产占各种自然灾害之首，因此提高水稻抗旱性成为保证我国粮食安全的重要内容。根系是植物主要的水分吸收器官，而深层根系能够保证植物在地表缺水情况下吸收到下层土壤中的水分，保证植物的正常生长，因此深根性是水稻抗旱研究的重要方向。基因转录水平上的调控是生物最重要的调控形式，转录组是基因功能及结构研究的基础和出发点。本项目基于已完成800份3个水稻群体的深根性表型数据，筛选出了一批表现稳定的典型深浅根材料，并将传统连锁QTL定位和全基因组关联分析有机结合，再利用根尖特定组织的转录组学发掘水稻深根控制位点及基因。进一步通过生物信息学分析，定量分析，基因敲除等手段开展候选基因的基因功能研究，为抗旱研究和育种提供支持。

Rice is the main food for chinese. Drought is the most serious abiotic stress that limits crop production under rainfed conditions. Therefore, enhancing drought resistance in rice is becoming a key strategy to stabilize rice production in rainfed areas. The plants’ roots, especially deep roots are the most important organ to absorb and translocate water from the deep soil under drought, so the plants’ ability to avoid drought stress mainly depends on their deep rooting performance. Deep rooting is usually represented by RDR (ratio of deep rooting). Transcriptional regulation is the most important component of bio-regulation in beings, and transcriptome is the base for the genetic research of genes’ function and structure. Based on the phenotyping of 3 populations with 800 rice germplasms, some typical deep and shallow rooting varieties are selected out, and some putative QTLs are detected through the combination of linkage-based and LD-based QTL mapping. In this project, transcriptome analysis by high-throughput sequencing is used to fine-mapping and discover the main-effect genes controlling deep rooting. Furthermore, bioinformatic analysis, real-time PCR and gene knock-down technology are applied to the exploration of their genetic mechanism.This research could improve our understanding of the genetic basis for drought resistance in rice and provide us useful information in molecular breeding of drought resistant rice.