A major challenge in agroforestry is the selection of the plant species involved in the systems. This issue is drawing more attention lately due to the changing climate conditions and Moringa oleifera represents a promising species to meet these climatic challenges. The adaptation potential and tolerance of Moringa to water stress was tested in this study. It included a controlled (hydroponic cultivation) and a field experiment in an arid area bordering the Bouhedma National Park (Governorate of Sidi Bouzid) in Tunisia. Water stress was induced by the use of polyethylene glycol (PEG-6000) to create different water potential levels (ψh) and included 0 (control), −0.5, −1 and −1.5 MPa. The growth of the stem and main root, relative growth rate (RGRh), and leaf area (LA) of Moringa seedlings subjected to 20 day of water stress was compared to the control. Additionally, Moringa seedlings were grown in the field for 16 months and their growth parameters were evaluated at the end of the experiment. Based on the results, the Moringa seedlings displayed a positive tolerance to water stress. Significant variations were found, such as growth delays in length, reaching up to 30% for the stems and 64% for the roots for ψh = −1.5 MPa. This water potential resulted in a 75% reduction of Relative Growth Rate (RGRh) per day for the water stress experiment (hydroponics), as a reaction of the plant to overcome the stress. Additionally, it had the highest negative effect on stem length and leaf area. As for the plants grown in the field, their main stem height increased by 43.13% and their number of branches by 45.34% per year. An overall (RGRh) of 0.44 per year was noted accompanied by a total phytomass of 0.46 and tree volume of 23.67 g cm−3. Based on the above it can be concluded that Moringa represent a promising species as an ecological solution for use in agroforestry systems, able to minimize the negative effects of drought and to rehabilitate and enhance the soil of arid zones.

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辣木 (Lam) 对水分胁迫和干旱生物气候条件的生长反应

农林业的一个主要挑战是选择系统中涉及的植物物种。由于气候条件的变化，这个问题最近引起了更多关注，辣木代表了应对这些气候挑战的有希望的物种。本研究测试了辣木对水分胁迫的适应潜力和耐受性。它包括在突尼斯与 Bouhedma 国家公园（西迪布兹德省）接壤的干旱地区进行受控（水培栽培）和田间试验。通过使用聚乙二醇 (PEG-6000) 产生不同的水势水平 (ψh) 并包括 0（对照）、-0.5、-1 和 -1.5 MPa 来诱导水分胁迫。茎和主根的生长，相对生长率（RGRh），将经受 20 天水分胁迫的辣木幼苗的叶面积 (LA) 与对照进行比较。此外，辣木幼苗在田间生长 16 个月，并在实验结束时评估它们的生长参数。根据结果​​，辣木幼苗对水分胁迫表现出积极的耐受性。发现了显着的变化，例如长度的生长延迟，当 ψh = -1.5 MPa 时，茎达到 30%，根达到 64%。这种水势导致水分胁迫实验（水培）每天的相对增长率 (RGRh) 降低 75%，这是植物克服胁迫的反应。此外，它对茎长和叶面积的负面影响最大。对于田间种植的植物，它们的主茎高度增加了 43。13%，他们的分支机构数量每年增加 45.34%。注意到每年 0.44 的总体 (RGRh) 伴随着 0.46 的总植物量和 23.67 g cm−3 的树木体积。基于上述，可以得出结论，辣木是一种有前途的物种，作为用于农林业系统的生态解决方案，能够最大限度地减少干旱的负面影响，并恢复和增强干旱地区的土壤。