Feldman Aryo B, Murchie Erik H, Leung Hei, Baraoidan Marietta, Coe Robert, Yu Su-May, Lo Shuen-Fang, Quick William P
School of Biosciences, University of Nottingham Malaysia Campus, Semenyih, Selangor Darul Ehsan, Malaysia.
School of Biosciences, University of Nottingham Sutton Bonington Campus, Sutton Bonington, Leicestershire, United Kingdom.
PLoS One. 2014 Apr 23;9(4):e94947. doi: 10.1371/journal.pone.0094947. eCollection 2014.
A high leaf vein density is both an essential feature of C4 photosynthesis and a foundation trait to C4 evolution, ensuring the optimal proportion and proximity of mesophyll and bundle sheath cells for permitting the rapid exchange of photosynthates. Two rice mutant populations, a deletion mutant library with a cv. IR64 background (12,470 lines) and a T-DNA insertion mutant library with a cv. Tainung 67 background (10,830 lines), were screened for increases in vein density. A high throughput method with handheld microscopes was developed and its accuracy was supported by more rigorous microscopy analysis. Eight lines with significantly increased leaf vein densities were identified to be used as genetic stock for the global C4 Rice Consortium. The candidate population was shown to include both shared and independent mutations and so more than one gene controlled the high vein density phenotype. The high vein density trait was found to be linked to a narrow leaf width trait but the linkage was incomplete. The more genetically robust narrow leaf width trait was proposed to be used as a reliable phenotypic marker for finding high vein density variants in rice in future screens.
高叶脉密度既是C4光合作用的一个基本特征，也是C4进化的一个基础性状，它确保了叶肉细胞和维管束鞘细胞的最佳比例和紧密程度，从而使光合产物能够快速交换。我们对两个水稻突变体群体进行了筛选，以寻找叶脉密度增加的植株，其中一个是具有cv. IR64背景的缺失突变体文库（12470个株系），另一个是具有cv. 台农67背景的T-DNA插入突变体文库（10830个株系）。我们开发了一种使用手持显微镜的高通量方法，更严格的显微镜分析证实了该方法的准确性。我们鉴定出8个叶脉密度显著增加的株系，作为全球C4水稻联盟的遗传材料。结果表明，候选群体中既有共享突变，也有独立突变，因此不止一个基因控制着高叶脉密度表型。我们发现高叶脉密度性状与窄叶宽度性状相关，但这种连锁是不完全的。我们建议将遗传上更稳定的窄叶宽度性状用作未来水稻筛选中寻找高叶脉密度变异体的可靠表型标记。
