Structural and functional traits driving Chloris flagellifera proliferation in arid saline environments

Abstract

Chloris flagellifera (Nees) P. M. Peterson is a species thriving in salt-affected regions across Punjab, Pakistan. To investigate intraspecific variations, six distinct populations were selected from diverse saline environments: (1) Pakka Anna and Sahian Wala from the least saline regions, (2) Jhalar and Kalar Kahar Lake from moderately saline areas, and (3) Uchali Lake and Khabbeki Lake from hyper-saline zones. These populations, originating from a range of salinity gradients, provide a unique opportunity to study the adaptive mechanisms of C. flagellifera to varying levels of soil salinity. Stomata from highly saline areas were small and narrowly elliptical, while they were larger and rhomboidal in moderately saline areas and circular in least saline areas. Populations from hyper-saline environments (Uchali Lake, Khabbeki Lake) displayed remarkable trait variation, including thicker epidermal layers, larger vascular bundles, and efficient osmotic adjustments, indicating their superior salt tolerance. Populations from least saline areas (Sahian Wala, Pakka Anna) showed structural features like thicker leaves and larger epidermal cells that enhance water retention. Moderately saline populations (Kallar Kahar Lake, Jhallar Lake) exhibited intermediate traits, balancing salt tolerance with efficient resource allocation. These anatomical and physiological responses suggest that C. flagellifera exhibits high adaptability to varying salinity stress. The study highlights the potential of hyper-saline populations for use in the reclamation of salt-affected soils, offering a sustainable approach to land restoration.