Surviving the desert's grasp: Decipherment phreatophyte Tamarix aphylla (L.) Karst. Adaptive strategies for arid resilience

Abstract

Phreatophytes play an important role in maintaining the ecological services in arid and semi-arid areas. Characterizing the interaction between groundwater and phreatophytes is critical for the land and water management in such areas. Therefore, the identification of key traits related to mitigating desertification in differently adapted T. aphylla populations was the focus. Fifteen naturally adapted populations of the prominent phreatophyte T. aphylla from diverse ecological regions of Punjab, Pakistan were selected. Key structural and functional modifications involved in ecological success and adaptations against heterogeneous environments for water conservation include widened metaxylem vessels in roots, enlarged brachy sclereids in stems/leaves, tissues succulence, and elevated organic osmolytes and antioxidants activity for osmoregulation and defense mechanism. Populations from hot and dry deserts (D_ratio: 43.17−34.88) exhibited longer roots and fine-scaled leaves, along with enlarged vascular bundles and parenchyma cells in stems. Populations inhabiting saline deserts (D_ratio: 38.59−33.29) displayed enhanced belowground biomass production, larger root cellular area, broadest phloem region in stems, and numerous large stomata in leaves. Hyper-arid populations (D_ratio: 33.54−23.07) excelled in shoot biomass production, stem cellular area, epidermal thickness, pith region in stems, and lamina thickness in leaves. In conclusion, this research highlights T. aphylla as a vital model for comprehending plant resilience to environmental stresses, with implications for carbon sequestration and ecosystem restoration.