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Salinity and heavy metal stresses are a great hindrance to the germination and development of plants. Nickel (Ni) is an indispensable micronutrient for plants at low concentrations. However, the proficiency depends upon the plant types. Citrullus colocynth is a medicinal cucurbit weed. The contemporary target of the study is to appraise the influence of combined stresses by varying concentrations of sodium chloride and nickel chloride on germination, morphology, biochemical ions, and physiology of C. colocynth. Germination percentage, root length, shoot length, fresh weight, dry weight, number of leaves, Na+, K+, Ca++, Cl-, Ni+, chlorophyll a and b, proline, SOD and CAT of C. colocynth were measured with nine combined levels (100 mM NaCl + 50 uM NiCl2), (200 mM NaCl + 50 uM NiCl2), (400 mM NaCl + 50 uM NiCl2), (100 mM NaCl + 100 uM NiCl2), (200 mM NaCl +100 uM NiCl2), (400 mM NaCl +100 uM NiCl2), (100 mM NaCl + 200 uM NiCl2), (200 mM NaCl + 200 uM NiCl2) and (400 mM NaCl +200 uM NiCl2). This experiment was conceded out in a completely randomized design with four replications. Germination percentage, root length, shoot length, fresh weight, dry weight, and the number of leaves, K+, Ca++, chlorophyll a, and b decreased by increasing stress levels while Na+, Cl-, Ni+, Proline, SOD, and CAT increased with increasing stress levels. This species has a positive morpho-physiological response under low(100mM NaCl, 50 uM NiCl2) and moderate (200mM NaCl, 100 uM NiCl2) combinations of salt and heavy metals while tolerance was observed under high-stress levels(400mM NaCl, 200 uM NiCl2). It is concluded that this species can be recommended for phytoremdiation against combined salt and heavy metal stresses.

Cenchrus ciliaris is a potential forage grass that is widely distributed in saline desert condition across Africa, Australia and Asia. To examine anatomical characteristics relating to ionic and nutritional contents in response to salinity, Cenchrus ciliaris populations from the naturally salt-affected region of the Cholistan Desert, Pakistan were collected. The experiment was planned in a completely randomized design (CRD) with four replications and four treatment levels (0, 100, 200, and 300 mM NaCl) in a hydroponic system. After six months of growth in nutrient solution anatomical characteristics relating to ionic and nutritional traits were studied. It was hypothesized that C. ciliaris at higher salt stress must have developed some specific structural adaptations, which are responsible for better survival under high salt stress. At root level, C. ciliaris showed decreased root thickness with greater proportion of parenchyma cells in cortical region and increased sclerification in cortex and pith regions at high salinity levels, which are vital for water conservation under osmotic stress. At stem level increased stem area, cortical and vascular bundle cell area were recorded with increase in salinity level of external growth medium. Salt tolerance in C. ciliaris mainly associated with restricted uptake of toxic Na+ and Cl− ions at roots, accompanied by increased concentration of K+ and Ca++ in shoot. Under high salinities, C. ciliaris showed increased epidermis thickness, well developed bulliform cells, and increased trichome density at leaf level. All these structural modification in this species may contribute towards water conservations under physiological stress that is caused by high level of soil salinity. Various nutritional traits such as crude protein, ash content, relative feed value, and net energy of lactation slightly improved with salinity. Present study revealed nutritional potential, ionic contents and anatomical adaptations of C. ciliaris to cope with salinity. As such this species can be used to produce valuable fodder under saline desert environment.

The role of ionic excretions and hyper-accumulation of salts through alterations of structural and functional traits in five populations of Suaeda vera Forssk. ex J.F. Gmel., a halophytic salt-indicator species of saline environments, was explored. Differently adapted populations of S. vera exhibited specific structural and functional responses for the survival in hyper-saline conditions. Better growth in population from moderately saline habitat (25-30 dS m

Deserts are generally prone to a number of ecological hazards which act as agents for the development of particularly a very diverse group of grasses, which can resist to salt stress through multiple morpho-anatomical and physio-biochemical mechanisms. Of such grasses, Cymbopogon jwarancusa is found inhabiting different saline patches of the Cholistan desert, so its different populations were selected from five saline habitats [least saline Derawar Fort (DF); moderately saline Trawaywala Toba (TW) and Bailahwala Dahar (BD), and high saline Ladam Sir (LS) and Pati Sir (PS)] and tested for their salt tolerance mechanism. Differentially adapted populations of this grass showed specific modifications in terms of anatomical features, mainly increased sclerification in both external hypodermis and internal endodermis, cortical layers, and increased size of xylem vessels with increase in salinity of the habitat. Increased endodermal thickness may control radial movement of water in roots. The reduction in leaf area is found to be the principal strategy that makes C. jwarancusa promising to attenuate the effects of the reduced availability of water under saline stress. Thick epidermis with dense cuticle and large bulliform cells area can be particularly considered as an important adaptation of this grass against physiological drought. Moreover, increased density of trichomes is found critical for checking undue water loss through the leaf surface and increase in these tissues at high salinity level may indicate that this species has better adapted to saline habitat.

Avian influenza or bird flu is a common problem of domestic and wild birds. Some of its strains are able to cross the species barrier and cause infection in various members of class Mammalia. In view of relatively lesser efficacy of vaccines, antiviral therapies remain the only choice for the sustenance of mammals acquiring this highly devastating infection. This study is based on the evaluation of antiviral potential of methanol extracts of eleven selected Cholistani plants. The methanol extracts were prepared by using dried plants material followed by concentrating in a rotary evaporator and finally air dried before dissolving in nanopure water. The suspension was filter sterilized and subjected to in ovo antiviral assays. The allantoic fluids were harvested and haemagglutinin (HA) titers were determined. Among the eleven plants evaluated all methanol extracts were found effective against AIV H9N2 except S. baryosma extract. The medicinal plants O. compressa, N. procumbens, and S. surattense were found to be more effective than others and they retained HA titers at 0 after challenge. The next in order were extracts of O. esculentum, H. salicornicum and S. fruticosa which kept HA titers at 4, 8 and 16 respectively. The extracts of H. recurvum, P. antidotale, S. icolados and A. aspera were found less effective than above mentioned plant extracts and they kept the HA titers at 32, 64, 128 and 256 respectively. These results led us to conclude that the medicinal plants of Cholistan region are a rich source of antiviral agent(s) against AIV H9N2 and could be a source of cost effective alternate therapeutics.

Natural populations of a desert halophyte Sporobolus ioclados were investigated to explore morpho-anatomical and physiological modifications at differently salt-affected habitats. Derawar Fort (DF) was the least affected site, Trawaywala Toba and Bailahwala Dahar (BD) were moderately saline sites and Ladam Sir (LS) and Pati Sir (PS) were highly saline sites. At root level, S. ioclados showed increased root cross-sectional area, epidermal and endodermal thicknesses, and greater proportion of cortical parenchyma as salinity level of the habitat increased. Sclerification of outer cortex was visible only at the highest saline site. Decreased stem area, epidermal cell area, cortical and vascular bundle cell area, and increased hypodermal thickness at stem level were recorded with increase in the salinity level of the habitats. At leaf level, S. ioclados showed smaller and thicker leaves, increased epidermis thickness, and well-developed bulliform cells, increased mesophyll area and increased trichome density under high salinities. The plants at high salinities were better adapted in terms of growth, exclusion, internal structure, and restricted uptake of Na + by roots, accompanied by increased concentration of K + and Ca 2+ in shoots. All these changes may be an evolutionary strategy that has been developed by the S. ioclados plants during the long process of evolution.

Five differently adapted natural populations of the native salt desert grass Lasiurus scindicus Henrard from Lesser Cholistan Desert (Pakistan) in South Punjab of east central Pakistan, were evaluated to examine their mechanism of adaptation to saline stress based on some key morpho–anatomical and physiological characteristics. Five ecotypes were collected from one saline site, two moderately saline sites, and two highly saline sites. Anatomical adaptations in each ecotype critically supported the physiological, but the adaptations were of specific nature depending on the type of each site’s normal habitat conditions. Higher salinities resulted in increased Na+, Cl−, Mg2+, Ca2+ and K+ content in root and shoot. At root level, some specific structural modifications like increased sclerification in cortical and pith regions, endodermal thickness, and number and size of xylem vessels are vital for water conservation under osmotic stress. Several characteristics were promising for increasing the plants ability to deal with osmotic stress, including at the stem level, increased sclerification, stem area, cortical region thickness and vascular bundle area, and at the leaf level, significant structural modifications such as leaf thickness, epidermal thickness, sclerenchymatous area, cortical area, metaxylem area and bulliform cell area were promising. All these may contribute towards water conservation, which ultimately account for ecotype survival under saline–induced physiological droughts.

Three differently adapted populations of sewan grass (Lasiurus scindicus Henr.) were evaluated for structural and functional adaptations to high salinity. The habitats were Derawar Fort (DF, least saline, ECe 15.21), Bailahwala Dahar (BD, moderately saline, ECe 27.56 dS m−1) and Ladam Sir (LS, highly saline, ECe 39.18 dS m−1) from within the Cholistan Desert. The adaptive components of salt tolerance in sewan grass were assessed by determining various morpho–anatomical and physiological attributes. The degree of salt tolerance of all three ecotypes of L. scindicus from the saline habitats was compared in a controlled hydroponic system to evaluate the adaptive components that are expected to be genetically fixed during a long evolutionary process. Salinity tolerance in the most tolerant LS population relied on increased root length and total leaf area, restricted uptake of toxic Cl−, increased uptake of Ca2+, high excretion of Na+, accumulation of organic osmolytes, high water use efficiency, increased root, thicker leaf and cortical region, intensive sclerification, large metaxylem vessels, and dense pubescence on abaxial leaf surface. The BD population (from moderately saline soil) relied on high Ca2+ uptake, Na+ excretion, epidermal thickness, large cortical cells, thick endodermis and large vascular tissue. The DF population (from less saline soil) showed a significant decrease in all morphological characteristics; however, it accumulated organic osmolytes for its survival under high salinities. Structural modifications in all three populations were crucial for checking undue water loss under physiological stress that is caused by high amounts of soluble salts in the soil.

Two populations of cogongrass [Imperata cylindrica (L.) Raeuschel], one from the saline regions of the Salt Range and the other from the non-saline regions of Faisalabad were assessed for salinity tolerance on the basis of some key morphological and physiological attributes. It was hypothesized that the tolerant population from the Salt Range must have developed some specific structural modifications, which are responsible for its better survival under high salinities. These adaptive components can be effectively used in modern technologies for improving degree of tolerance of other sensitive crops. The population from the Salt Range markedly excelled the Faisalabad population in terms of growth and physiological attributes measured in this study. The Faisalabad population of I. cylindrica was unable to survive at the highest salt level (200 mM NaCl). The tolerance of the Salt Range population to salt stress was found to be related to high accumulation of organic osmotica, particularly total free amino acids and proline as well as Ca2+ in the shoot. The distinctive structural modifications in the Salt Range population were found to be enhanced succulence, well-developed bulliform cells in leaves and smaller stomatal area.

Five ecotypes of Panicum antidotale Retz. adapted to diverse habitats were subjected to drought stress to evaluate their drought tolerance in relation to adaptive anatomical structures. The ecotype from non-stressed habitat had intensive sclerification as well as crystallization in parenchymatous cells, which help prevent water loss. The ecotype from drought-prone habitat had well-developed metaxylem vessel area for better conduction of water and nutrients, and pith area for better storage of water. The ecotype collected from salinity-affected habitat as well as that from saline and waterlogged habitat showed extensive sclerification in the vascular region, which is vital for preventing water loss. The ecotype from a salinity- and drought-prone habitat showed increased metaxylem vessel number and formation of additional metaxylem vessels in the pith region for better conduction, multi-layer exodermis and intensive sclerification for prevention of water loss, and increased parenchymatous region for better ...

The inland vegetation of saline patches in the Cholistan desert faces extreme environmental conditions including predominantly salt stress and limited resource availability. Changes in the salinity gradients may lead to gradual variation in response of individual plant species that ultimately affect community structure and composition. The present study was conducted to determine spatial distribution of individual species along a salinity gradient in the Cholistan desert in relation to their life form and tolerance limits. The results showed variable responses of these species in spatial distribution against the salinity gradient. The plants differed considerably in their tolerance level due to development of differential adaptive strategies under extreme salinities. Excretory species like Aeluropus lagopoides and Sporobolus ioclados dominated the sites with highest salinities along with the leafy succulent Suaeda fruticosa. Stem succulents dominated moderate salinities along with spreading stoloniferous ...

Rapid growth of the world population, started in 1950, resulted in an estimated recent population of more than seven billion. Indian sub-continent is the most densely populated and fastest growing region. The desert ecosystem encompasses some 313,851 km2 area including Thar, Kharan, Cholistan, Thal and Indus valley plains in this region. The biodiversity includes some estimated 764 species of desert flora and 769 species of fauna, which includes 123 mammals, 540 birds, 96 reptiles and 10 amphibians. The desert dwellers lead a nomadic to semi-nomadic life, moving from one place to another in search of water and fodder for their animals and trade. Deserts are already the most fragile ecosystems and facing an unprecedented vulnerability mainly due global warming phenomena by pushing its biological resources to their limits. There is a dire need to wisely use desert resources on sustainable basis, so that a symbiotic relationship between man and ecosystem may be guaranteed.

In Pakistan, Lehri/Jindi evergreen open scrub forest is a characteristic habitat of critically or locally endangered species including Punjab urial (Ovis vignei punjabiensis) and leopard (Panthera pardus), and the important game species desert hare (Lepus nigricollis), black francolin (Francolinus francolinus), grey francolin (Francolinus pondicerianus), see–see partridge (Ammoperdix griseogularis) and chukor partridge (Alectoris chukar). Four separate fenced enclosures were established to maintain captive Punjab urial population in a semi-wild state. Vegetation surveys were conducted through permanently laid quadrats to explore its impact on native flora in 1987–1992 before the fencing was installed and then 2003–2007 over a decade after the fencing was installed.

Some ecologically different ecotypes of Panicum antidotale Retz. were evaluated for drought tolerance in relation to growth parameters and leaf structural modifications. These ecotypes were adapted to normal non-stressed (agricultural field AF, and sludge of disposal channel SDC), drought-stressed (along roadside AR), salinity-stressed (forest plantation FP), waterlogging and salinity-stressed (inside disposal channel IDC), and drought plus salinity-stressed (barren area BA). On the basis of genetic variability in leaf structural modifications, each ecotype adopted specific strategies to tolerate the extremity of drought stress. The AF and SDC ecotypes relied on water conservation and survival rather than growth and structural modifications by developing epidermis and sclerenchyma on both leaf surfaces. The AR developed xerophytic foliar characteristics in addition to maintaining growth and development under stressed conditions like thick leaves, well-developed bulliform cells, and intensive sclerification. The FP ecotype developed efficient strategy for drought tolerance such as reduced and fibrous leaves, smaller metaxylem vessels, and highly developed bulliform cells. The ecotype IDC relied more on water conservation by increasing leaf epidermal thickness and decreasing stomatal area and density. The ecotype BA showed critical structural adaptations such as thin leaves, extremely developed bulliform and reduced metaxylem area, and parenchyma extensions above vascular bundles. Based on the strategies adopted for drought tolerance, the tolerance level of these ecotypes were rated as BA > AR > FP > IDC > SDC > AF.

Populations of three salt tolerant forage grasses (Cynodon dactylon, Imperata cylindrica, and Sporobolus arabicus) were collected from the salt-affected soils of the Salt Range and normal non-saline soils of the Faisalabad region to assess their mechanism of adaptation to saline stress by determining ion relations and some specific anatomical modifications. The population of S. arabicus from the Salt Range showed increased growth (root and shoot length, and root and shoot dry weights) under saline conditions. Salt tolerance in this species was related to structural modifications such as increased area of root, stem, leaf blade, and leaf sheath for toxic ion accumulation, increased vesicular hair density in leaves and aerenchyma formation in leaf sheath for ion exclusion. Uptake of toxic ions was high in the Salt Range population of C. dactylon and salt tolerance was related to ion exclusion through specific leaf structural modifications such as vesicular hairs. Salt tolerance in the Salt Range population of I. cylindrica was mainly associated with restricted uptake of toxic Na+ and Cl− at root level, and accumulation of toxic ions via increased succulence in leaf blades and leaf sheaths in addition to some excretion of toxic ions through leaf sheath aerenchyma.

Two populations, one from lesser saline Derawar Fort (DF) and the other from highly saline Ladam Sir (LS) in the Cholistan desert, for each of the five grass species, Aeluropus lagopoides, Cymbopogon jwarancusa, Lasiurus scindicus, Ochthochloa compressa, and Sporobolus ioclados were examined to investigate the influence of salinity on structural and functional characteristics of stomata. Salinity tolerance in A. lagopoides mainly depended on controlled transpiration rate (E) and high water-use efficiency (WUE), which was found to be regulated by fewer and smaller stomata on both leaf surfaces as well as stomatal encryption by epidermal invaginations. C. jwarancusa had sunken stomata on the abaxial surface only, which largely reflected a reduced E, but less affected stomatal conductance (g s) or WUE. L. scindicus had fewer but larger stomata along with hairs/trichomes which may function to avoid water loss through transpiration, and hence, to attain a high WUE. In O. compressa stomata were found only on the abaxial surface and these were completely encrypted by epidermal invaginations as well as a dense covering of microhairs, which was associated with a low E and high WUE under salinity stress. In S. ioclados, the traits of increased stomatal density and decreased stomatal area may be critical for stomatal regulation under salt-prone environments. High stomatal regulation depended largely on stomatal density, area, and degree of encryption under salinity, which is of great ecophysiological significance for plants growing under osmotic stresses.

Five distinct habitats along salinity gradient were explored for plant ecological attributes including soil plant interaction, vegetation composition and species distribution in the Cholistan desert. Higher saline sites supported Sporobolus ioclados with Aeluropus lagopoides, Cymbopogonjwarancusa, Ochthochloa compressa, Haloxylon recurvum and Suaeda fruticosa , whereas moderately saline habitats supported predominantly Fagonia indica, C. jwarancusa and O. compressa . The community structure and composition of each habitat type were very specific, the most dominant component being S. ioclados . Each species has very specific relation to different environmental variables, and this reflects the habitat status, ecological adaptations and stress tolerance degree of the individual species. On the whole, it can be concluded that salinity alone was not responsible for the distribution of species at salt affected habitats.

To examine anatomical adaptations in a potential forage grass, Imperata cylindrica (L.) Raeuschel, a population was collected from the natural salt-affected soils of the Salt Range, Pakistan. Using a hydroponic system, the degree of salt tolerance in terms of structural modifications in the Salt Range ecotype was compared with that in an ecotype collected from a normal non-saline habitat of the Faisalabad region. The Salt Range ecotype was superior to the Faisalabad ecotype in biomass production under saline conditions. High salt tolerance of the Salt Range ecotype was associated with increased succulence in root and leaf (mainly midrib), formation of aerenchyma in leaf sheath, increased vascular bundle area, metaxylem area and phloem area, highly developed bulliform cells on leaves and increased sclerification in root and leaf. Furthermore, both stomatal density and stomatal area were considerably reduced under high salinities in the Salt Range ecotype.

Sporobolus arabicus Boiss. is a perennial stoloniferous grass that prefers a saline or desert habitat. A natural population of Sporobolus arabicus growing in a salty area was compared with a normal nonsaline population. The salt-tolerant population showed better growth than its counterpart. Physioanatomical adaptations to saline environments in the salt-tolerant population were very specific. They included restricted toxic ion uptake, production of organic osmolytes, sclerification in roots, succulence in stem, and development of vesicular hairs on the leaves. These adaptations were not only for the excretion of toxic ions but also for the accumulation of inorganic ions in the parenchymatous tissue. The Salt Range population maintained osmotic and water potential, accumulated lower amounts of Na+ and Cl- in the roots and shoots, and had higher organic osmolytes, increased sclerification in the roots, and succulence in the stems and leaves.

In the title compound, C7H8N2O4S, the nitro group is twisted by 9.61 (2)° relative to the benzene ring. In the crystal, molecules are linked by N—H...O and N—H...(O,O) hydrogen bonds between the amino and sulfonyl groups, forming layers parallel to (001).