Water conservation strategies in big cordgrass (Desmostachya bipinnata L.) for ecological success in hyper-arid and saline-arid environments

Abstract

This study was conducted to investigate water conservation strategies in the above ground parts of Desmostachya bipinnata L., a perennial grass growing in populations of arid areas of the Punjab to identify variability in the anatomical traits that enable them to survive in water deficit conditions. Key structural modifications contributing to the ecological success and adaptation against heterogeneous environments included water conservation via development of additional water storage parenchyma, efficient conduction of solutes through wide metaxylem vessel (7947 µm²), minimization of water loss by intensive sclerification in some populations from Kallar Kahar (hyper-saline lake) and Pakka Anna (highly saline wasteland with D_ratio:13.29) to avoid water loss. Populations from the most dry habitats, that is, in Cholistan (inter-dune desert flat with D_ratio:43.17) had numerous small metaxylem vessels (1727 µm²). Saluwali (Cholistan Desert plain D_ratio:30.4) populations showed intensive sclerification in stem vascular region and high density, wider metaxylem vessel oriented in dimensions different than other populations. A very unique feature observed in stems of Cholistan desert margin Kachakho, Pirowal plantation and Saluwali populations was the development of single-large metaxylem vessels instead of a pair usually found in plants. Another characteristic feature observed in stems, leaves and leaf sheath of some populations was differentially developed aerenchyma and bulliform cells ranging from small to large prominent and deeply inserted. In conclusion, D. bipinnata populations showed high but habitat-specific variability among the traits recorded, which provided this species a great potential to colonize arid and salt-affected areas.

Keywords:

• Aerenchyma
• bulliform cells
• metaxylem
• perennial grass
• sclerification

Acknowledgment

The data presented in this manuscript is extracted from the PhD thesis of Miss Safura Bibi (2010-ag-859) submitted to University of Agriculture, Faisalabad. This manuscript has been produced from independent studies and no funding agency is involved in execution of this research work. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors

Author contributions

Safura Bibi conducted an experiment and compiled the manuscript. Muhammad Sajid Aqeel Ahmad as a major supervisor guided the first author in planning and execution of the experiment, and, in statistical analysis. Mansoor Hameed helped proofread the manuscript. Ambreen Khadija Alvi provided technical assistance while writing this manuscript.

Disclosure statement

All authors declare the there is no conflict of interest with any individual, institution, or academic and nonacademic organization.