Chen Da-Gang, Zhou Xin-Qiao, Chen Ke, Chen Ping-Li, Guo Jie, Liu Chuan-Guang, Chen You-Ding
Rice Research Institute, Guangdong Rice Engineering Laboratory, Guangdong Key Laboratory of New Technology in Rice Breeding, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People's Republic of China.
Mol Breed. 2022;42(2):6. doi: 10.1007/s11032-022-01275-y. Epub 2022 Jan 27.
Leaf thickness is an important trait in rice ( L.). It affects both photosynthesis and sink-resource efficiency. However, compared to leaf length and length width, reports seldom focused on leaf thickness due to the complicated measurement and minor difference. To identify the quantitative trait loci (QTL) and explore the genetic mechanism regulating the natural variation of leaf thickness, we crossed a high leaf thickness variety Aixiuzhan (AXZ) to a thin leaf thickness variety Yangdao No.6 (YD 6) and evaluated 585 F individuals. We further use bulked sergeant analysis with whole-genome resequencing (BSA-seq) to identify five genomic regions, including chromosomes 1, 6, 9, 10, and 12. These regions represented significant allele frequency differentiation between thick and thin leaf thickness among the mixed pool offspring. Moreover, we conducted a linkage mapping using 276 individuals derived from the F population. We fine-mapped and confirmed that chromosome 9 contributed the primary explanation of phenotypic variance. We fine-mapped the candidate regions and confirmed that the chromosome 9 region contributed to flag leaf thickness in rice. We observed the virtual cellular slices and found that the bundle sheath cells in YD 6 flag leaf veins are fewer than AXZ. We analyzed the potential regions on chromosome 9 and narrowed the QTL candidate intervals in the 928-kb region. Candidate genes of this major QTL were listed as potentially controlled leaf thickness. These results provide promising evidence that cloning leaf thickness is associated with yield production in rice.
The online version contains supplementary material available at 10.1007/s11032-022-01275-y.
叶片厚度是水稻（Oryza sativa L.）的一个重要性状。它影响光合作用和库源效率。然而，与叶片长度和长宽比相比，由于测量复杂且差异较小，关于叶片厚度的报道很少。为了鉴定控制叶片厚度自然变异的数量性状位点（QTL）并探索其遗传机制，我们将厚叶品种矮秀占（AXZ）与薄叶品种扬稻6号（YD6）杂交，并对585个F个体进行了评估。我们进一步利用全基因组重测序的混合分组分析法（BSA-seq）鉴定出5个基因组区域，包括第1、6、9、10和12号染色体。这些区域在混合池后代的厚叶和薄叶之间表现出显著的等位基因频率差异。此外，我们利用来自F群体的276个个体进行了连锁图谱分析。我们精细定位并证实第9号染色体对表型变异起主要作用。我们对候选区域进行了精细定位，并证实第9号染色体区域对水稻剑叶厚度有影响。我们观察了虚拟细胞切片，发现YD6剑叶叶脉中的维管束鞘细胞比AXZ少。我们分析了第9号染色体上的潜在区域，并将QTL候选区间缩小到928 kb区域。该主要QTL的候选基因被列为可能控制叶片厚度的基因。这些结果为克隆与水稻产量相关的叶片厚度提供了有力证据。
在线版本包含可在10.1007/s11032-022-01275-y获取的补充材料。
