Centre of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, India.
Department of Genetics, Osmania University, Hyderabad, India.
Plant Biotechnol J. 2022 Sep;20(9):1701-1715. doi: 10.1111/pbi.13840. Epub 2022 May 21.
Chickpea production is vulnerable to drought stress. Identifying the genetic components underlying drought adaptation is crucial for enhancing chickpea productivity. Here, we present the fine mapping and characterization of 'QTL-hotspot', a genomic region controlling chickpea growth with positive consequences on crop production under drought. We report that a non-synonymous substitution in the transcription factor CaTIFY4b regulates seed weight and organ size in chickpea. Ectopic expression of CaTIFY4b in Medicago truncatula enhances root growth under water deficit. Our results suggest that allelic variation in 'QTL-hotspot' improves pre-anthesis water use, transpiration efficiency, root architecture and canopy development, enabling high-yield performance under terminal drought conditions. Gene expression analysis indicated that CaTIFY4b may regulate organ size under water deficit by modulating the expression of GRF-INTERACTING FACTOR1 (GIF1), a transcriptional co-activator of Growth-Regulating Factors. Taken together, our study offers new insights into the role of CaTIFY4b and on diverse physiological and molecular mechanisms underpinning chickpea growth and production under specific drought scenarios.
鹰嘴豆的生产容易受到干旱胁迫的影响。确定干旱适应的遗传组成对于提高鹰嘴豆的生产力至关重要。在这里，我们提出了精细定位和特征描述'QTL-热点'，这是一个控制鹰嘴豆生长的基因组区域，对干旱条件下的作物生产有积极影响。我们报告称，转录因子 CaTIFY4b 的非同义取代调节鹰嘴豆的种子重量和器官大小。在 Medicago truncatula 中异位表达 CaTIFY4b 可增强水分亏缺下的根生长。我们的结果表明，'QTL-热点'中的等位基因变异通过调节生长调节因子（GRF）相互作用因子 1（GIF1）的表达，改善了开花前的水分利用、蒸腾效率、根系结构和冠层发育，使鹰嘴豆在终末干旱条件下实现高产。基因表达分析表明，CaTIFY4b 可能通过调节生长调节因子的转录共激活因子 GRF-INTERACTING FACTOR1（GIF1）的表达来调节水分亏缺下的器官大小。总之，我们的研究提供了鹰嘴豆生长和生产的新见解，以及在特定干旱情况下的不同生理和分子机制。
