Anatomical and physiological features modulate ion homeostasis and osmoregulation in aquatic halophyte Fimbristylis complanata (Retz.) link

• Published in: Acta physiologiae plantarum Vol. 44; no. 6
• Main Authors: Kaleem, Muhammad, Hameed, Mansoor, Ahmad, Farooq, Ashraf, Muhammad, Ahmad, Muhammad Sajid Aqeel
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2022; Springer Nature B.V
• Subjects: Agriculture; Aquatic habitats; Aquatic populations; Biomedical and Life Sciences; Calcium ions; Fimbristylis complanata; Foothills; Halophytes; Homeostasis; Life Sciences; Original Article; Osmoregulation; Plant Anatomy/Development; Plant Biochemistry; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Population; Populations; Salinity; Salinity effects; Salinity tolerance; Salt tolerance; Salts; Sodium chloride; Thickness; Water loss; Osmoregulation; Salt tolerance; Sedges; Ion homeostasis; Morpho-anatomical adaptations; Physiological variations
• ISSN: 0137-5881; 1861-1664
• DOI: 10.1007/s11738-022-03400-y

Fimbristylis complanata manifests several biochemical and anatomical modifications to mitigate salinity-induced ionic disturbance. Three populations from salt-affected aquatic habitats were evaluated to assess degree of salinity tolerance and ion homeostasis. The collection sites were HR-Rasool headworks, LR-Lillah-Khewra foothills and SH-Sahianwala with ECe 19.45, 31.36 and 47.49 dS m −1 , respectively. The populations were established in plastic containers and then three salt (NaCl) treatments (0, 200, 400 mM) were maintained. The experiment was laid in a completely randomized design (CRD) with three replicates. The SH population collected from hyper-saline habitat was the most salt tolerant mainly because of its capability to maintain root and shoot dry biomass accompanied by higher sequestration of Na + . Enhanced accumulation of Ca 2+ and other key osmolytes in SH population played a key role in osmotic adjustments and maintenance of membrane integrity. The reduction in tissue K + was observed in all populations due to the antagonistic effect of Na + . Anatomical traits like increased epidermal thickness and metaxylem area greatly contributed to ionic homeostasis in all three populations. The increase in anatomical traits was more pronounced in SH population. Increased leaf epidermal thickness in SH population was particularly helpful in tolerating low soil osmotic potentials by preventing water loss from the leaves. Increased aerenchyma in SH same population helped to store surplus water, salts and gases. These findings suggested that F. complanata exhibited enhanced salt tolerance by regulating the ion homeostasis and osmoregulation through a variety of morphological, biochemical and anatomical features.