Department of Agricultural and Biological Sciences, Faculty of Science and Technology, Uganda Christian University, P.O. Box 4, Mukono, Uganda.
National Coffee Research Institute, National Agricultural Research Organization, P.O. Box 185, Mukono, Uganda.
Sci Rep. 2020 Jan 21;10(1):862. doi: 10.1038/s41598-020-58035-1.
Effective phenotyping for drought resistance is a pre-requisite for identification of modest crop varieties for farmers. For neglected and underutilized crops such as Solanum aethiopicum Shum group, no drought screening protocol based on rigorous iterations has been documented. A split-plot nested treatment structure was arranged in an experiment to identify growth stage-specific watering thresholds for this crop. Three plant growth stages (main plot; seedling, vegetative and flowering), watering regime at plant growth stage (2 regimes; well-watered and drought stressed) and day since last watering at plant growth stage were evaluated for soil moisture content (SMC), leaf wilting score (LWS), number of green leaves per plant (LPP) and leaf blade width (LBW). Highly significant differences (p < 0.001) were found at the different plant growth stages, watering regime (WR) within plant growth stage, and day within WR and plant growth stage. Under drought stress treatment, SMC declined exponentially at each stage. The earliest leaf wilting, reduction in LPP and LBW were generally observed at flowering followed by vegetative and slowest at the seedling stage. For future effective drought phenotyping studies in S. aethiopicum Shum and related crops, we recommend setting minimum drought stress treatments below 18% SMC at which the LWS is ≥2 at the vegetative.
有效抗旱表型鉴定是鉴定适合农民种植的中轻度作物品种的前提。对于被忽视和利用不足的作物，如茄属埃塞俄比亚组，没有基于严格迭代的抗旱筛选方案。本研究采用裂区嵌套处理结构，确定该作物各生长阶段的具体浇水阈值。本研究评估了三个植物生长阶段（主区；幼苗、营养生长和开花）、生长阶段的浇水制度（2 种制度；充分浇水和干旱胁迫）和生长阶段最后一次浇水后的天数对土壤水分含量（SMC）、叶片萎蔫评分（LWS）、每株绿叶数（LPP）和叶片宽度（LBW）的影响。在不同的植物生长阶段、生长阶段内的浇水制度（WR）和 WR 内的天数之间都发现了非常显著的差异（p<0.001）。在干旱胁迫处理下，各阶段 SMC 呈指数下降。在开花期，叶片最早萎蔫，LPP 和 LBW 减少，其次是营养生长期，最慢的是幼苗期。对于未来在埃塞俄比亚茄属及其相关作物中进行有效的干旱表型研究，我们建议将最小干旱胁迫处理设定为 SMC<18%，此时在营养生长阶段，LWS≥2。
