多倍体育种为木薯育种提供了一个重要途径。前期研究表明，与对照相比，同源四倍体通过调节气孔和增强叶片细胞抗氧化能力而增强了木薯的耐旱性。通过二代测序，在木薯新品种“新选048”同源四倍体中筛选到86个特异干旱响应的长链非编码RNA（lncRNAs）和一批mRNAs。本项目在前期研究基础上，筛选“新选048”同源四倍体中差异表达且与气孔调节或抗氧化相关的mRNAs。以“新选048”和“华南205”两个木薯品种及其同源四倍体为材料，通过荧光定量PCR检测进一步筛选候选mRNAs；通过共表达和共位置分析获得一批在同源四倍体中特异表达且靶向候选mRNAs的lncRNAs，利用荧光定量PCR对lncRNAs及其靶标进行表达验证，挑选相关lncRNAs及其靶基因，通过反向遗传学策略鉴定它们的生物学功能。本项目将为后期深入研究lncRNA耐旱的分子机制奠定基础，对木薯高产耐旱育种有重要的指导意义。

Polyploidy provided an important breeding approach for cassava (Manihot esculenta Crantz) to drought tolerance. Previously, it was indicated that autotetraploid cassava showed obviously stronger drought resistance than the diploid progenitor via regulating stomatal as well as enhancing the antioxdiant capacity of leaf cells to adapt drought stress. Eighty-six drought responsive long non-coding RNAs (lncRNAs) and a set of mRNAs specifically expressed were identified using next generation sequencing in new variety Xinxuan 048’ autotetraploidy. In this project, based on previous studies, we want to screen the differential expressed genes related with regulating stomatal or antioxidant in 4x ‘Xinxuan 048’ sample. In order to screen the candidate mRNAs further, we used the quantitative real time PCR to detect the relative expression of the differential expressed genes in two diploid progenitor and autotetraploid cassava. Co-expressed and co-located analysis were used to identify the trans target and cis target gene of the drought responsive lncRNAs specifically in 4x cassava. The lncRNAs targeted the candidated mRNAs were selected. The expression of the lncRNAs and the target genes were validated using quantitative real time PCR. The lncRNAs interested together with their targets were selected and the reverse genetic approach was used to validate the function of the lncRNAs toghther with their target genes. This project will lay the foundation for further exploring the molecular meshanism of drought tolerance controlled by lncRNAs, and also would be of importance for high-yield and drought resistance cassava breeding.