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Three Cenchrus species (C. biflorus, C. ciliaris, and C. orientalis) were collected from different ecological regions in the Punjab and Khyber Pakhtoonkhwa during July to September 2020 to evaluate tolerance to multiple abiotic stresses (aridity, salinity, and cold). Growth and biomass production was the maximum in C. biflorus, C. ciliaris, and C. orientalis under aridity stress. Aerenchyma formation and vascular tissue increased significantly in roots under aridity. In C. ciliaris, aerenchyma formation was recorded under cold stress. Root vascular tissue was higher under normal conditions (26.7%) and aridity (30.4%) stress in C. ciliaris. Stem parenchyma (29.1%) and vascular tissues (35.5%) showed an increase in C. biflorus under aridity, while mechanical tissue (33.6%) increased significantly under salinity stress. In C. biflorus and C. ciliaris, extensive sclerification was recorded in the stelar region under aridity stress. The stem radius of C. orientalis was greatest under salinity (27.0%) and cold (29.1%) stress, while parenchyma tissue was smaller (12.1%) under cold stress. Leaf thickness generally increased under abiotic stresses, and the maximum (43.0%) thickness was recorded in C. biflorus under aridity stress. Cenchrus biflorus, C. ciliaris, and C. orientalis showed strong association among morphological and leaf anatomical traits under aridity stress. Cenchrus orientalis showed high sclerification outside the vascular bundles of the leaf sheath. In saline conditions, vascular bundles were sclerified and enlarged. In and outside the vascular bundles of leaf blades, extensive sclerification was observed under cold stress conditions. Modifications in structural and functional traits were critical for the ecological success of Cenchrus species for survival in multiple environmental stresses. [ABSTRACT FROM AUTHOR]

Salt excretory halophytes are the major sources of phytoremediation of salt-affected soils. Cressa cretica is a widely distributed halophyte in hypersaline lands in the Cholistan Desert. Therefore, identification of key physio-anatomical traits related to phytoremediation in differently adapted C. cretica populations was focused on. Four naturally adapted ecotypes of non-succulent halophyte Cressa cretica L. form hyper-arid and saline desert Cholistan. The selected ecotypes were: Derawar Fort (DWF, ECe 20.8 dS m−1) from least saline site, Traway Wala Toba (TWT, ECe 33.2 dS m−1) and Bailah Wala Dahar (BWD, ECe 45.4 dS m−1) ecotypes were from moderately saline sites, and Pati Sir (PAS, ECe 52.4 dS m−1) was collected from the highly saline site. The natural population of this species was collected and carefully brought to the laboratory for different structural and functional traits. As a result of high salinity, Na+, Cl–, K+, and Ca2+ content significantly increased at root and shoot level. At root level, some distinctive modifications such as increased sclerification in vascular bundles, enlarged vascular bundles, metaxylem vessels, phloem region, and storage parenchyma (cortex) are pivotal for water storage under extreme arid and osmotic condition. At the stem level, enhanced sclerification in outer cortex and vascular bundles, stem cellular area, cortical proportion, metaxylem and phloem area, and at the leaf level, very prominent structural adaptations were thicker and smaller leaves with increased density of salt glands and trichomes at surface, few and large stomata, reduced cortical and mesophyll parenchyma, and narrow xylem vessels and phloem area represent their non-succulent nature. The ecotype collected from hypersaline environments was better adapted regarding growth traits, ion uptake and excretion, succulence, and phytoremediation traits. More importantly, structural and functional traits such as root length and biomass, accumulation of toxic ions along with K+ in root and shoot, accumulation of Ca2+ in shoot and Mg2+ in root, excretion of toxic ions were the highest in this ecotype. In conclusion, all these alterations strongly favor water conservation, which certainly contributes to ecotypes survival under salt-induced physiological drought. Naturally adapted salt tolerant plants provide exceptional material for exploring adaptive mechanisms they use to confront high salt concentrations. Cressa cretica is a hypersaline hyperarid desert colonizer, which was previously underexplored. In the present study, we focused on the new insight on relationship among anatomical modifications, salt accumulation and excretion and phytoremediation potential of this rare species. [ABSTRACT FROM AUTHOR]

Micro and macro-morphological features contribute to plants' tolerance to a variety of environmental pollutants. The contribution of such structural modifications in the phytoremediation potential of Diplachne fusca populations collected from five saline habitats were explored when treated with 100 to 400 mM NaCl for 75 days along with control. Structural modifications in the populations from the highest salinity included development of aerenchyma in stem instead of chlorenchyma, absence of excretory hairs in stem, and exceptionally large trichomes on the leaf surface to help excretion of excess salt. Large parenchyma cells provided more space for water and solute storage, while broad metaxylem vessels were linked to better conduction water and nutrients, which ultimately excreted via glandular hairs, microhairs, and vesicular hairs. Broad metaxylem vessels and exceptionally long hairs observed in the populations collected from 52 dS m−1. In conclusion, large stem aerenchyma, exceptionally large trichomes on the leaf surface, and tightly packed outer cortical region in roots with intensive sclerification just inside the epidermis accompanied with salt excretion via glandular hairs, microhairs, and vesicular hairs were the main anatomical modifications involved in the phytoremediation potential of D. fusca in hyper-saline environments. Morpho-anatomical characteristics of the differently adapted populations of Diplachne fusca has never been reported. In particular, structural variation in their mechanism of adaptation for salinity tolerance was investigated for the first time in current study. [ABSTRACT FROM AUTHOR]

The main aim of current study was to perform in silico functional analysis of all reported RPIA mutations. In silico analysis was done using different tools i.e. trRosetta tool, Autodock Vina, PatchDock and iMODS. Among all the reported mutations, lowest percentage identity of 4.69% with wild-type protein was shown by splice site mutation, while highest percentage identity of 78.78%, was shown by p.Ser61Val mutation. In protein-substrate docking, wild-type protein was docking with substrate with 11 different bonds. However in case of mutant protein highest interaction with substrate molecule was shown by mutant p.Ile257Thr proteins via 13 different bonds, while lowest interaction was noted in mutant p.Asn255Ilefs17Term protein via 5 bonds. From the results, it was concluded that the binding of RPIA with ribose 5-phosphate is altered by the type of amino acid substitution, as well as the nature and number of bonds, which are capable to influence its biological activity. [ABSTRACT FROM AUTHOR]

Forty-nine accessions were collected from arid and semi-arid areas of Pakistan to explore adaptive components in red-grained wheat (Triticum aestivum L.). Single-line selections of these accessions were grown on an arid and a control site; that is, Uchkera Farm (UF) and Botanical Garden (BG), Faisalabad. The accessions grown at BG exhibited significantly better biomass and grain yield production than those grown at UF. Accession Ck5 from Chakwal produced the maximum grain yield (17.7 g plant−1) at BG and Jm3 (8.1 g plant−1) at UF. Among the eight accessions selected for further anatomical studies, Dg2 showed increased yield per plant at UF, which was related to root modifications like increased cortical region thickness, endodermal cell area, vascular region thickness, metaxylem area, and root hair length. Stem modifications included increased vascular bundle area, phloem area and stomatal density, while leaves showed increased cuticle thickness, bulliform cell thickness, trichome density, and length. Increased stomatal density and area were also found. Accession Jm3 showed a decrease in yield at UF. Root modifications in Jm3 included increased epidermal cell area, sclerenchymatous thickness, endodermal cell area, and root hair length. Stem modifications in this accession included increased stem cellular region thickness and sclerenchymatous cell area. Leaves had increased abaxial epidermal cell area, trichome number and length, and abaxial stomatal density. In conclusion, morpho-anatomical characteristics varied greatly in the red-grained wheat accessions at both experimental sites that have potential for incorporation into breeding efforts for drought tolerance in modern wheat cultivars. [ABSTRACT FROM AUTHOR]

Seven local landraces of common and durum wheat (Triticum aestivumL. andT. durumL.) from the arid and semi-arid areas of the Sultanate of Oman were examined for specific leaf and stem structural features for water conservation. On the basis of shoot fresh and dry weights (g plant−1), degree of tolerance to drought and salt stresses in these wheat landraces/cultivars can be ranked as S-24 > J-305 > Sarraya > Senain > Cooley > MH-97 > Missani>Hamira > Shwairaa. Modifications related to water conservation were found to be high degree of sclerification, succulence in leaf and stem, low resistance to water conductance in vascular tissue, and pubescence on leaf surface. The salt and drought tolerant cultivar S-24 showed high proportion of chlorenchyma and intensive sclerification in stem structure, and well-developed bulliform cells and dense pubescence on the leaves. These modified features were poorly developed in lesser stress tolerant Omani wheat landraces like Hamira and Shwairaa. Accession Senain also showed stem succulence (solid stem), an important xeromorphic feature. Structural modifications in landrace Missani were found to be increased sclerification in vascular tissue and high number of metaxylem vessels and high proportion of parenchyma in stem, and highly developed bulliform cells in leaf. Overall, the promising anatomical traits in highly stress tolerant landraces/cultivars were chlorenchyma in stem, rigorous sclerification in parenchyma and around vascular tissue, stem and leaf succulence, and enhanced ratio of major conducting tissue. [ABSTRACT FROM PUBLISHER]