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In modern agriculture, soil salinity stress has been extensively studied by researchers owing to its disastrous impacts on soil and plant health. Zinc (Zn) is an essential micronutrient . Crucial role of Zn in regulating plant growth under salinity stress has been well documented. Current research consisted of two studies, first study was aimed at comparing three organic (i.e. sugarcane filter cake, farmyard manure and poultry manure) and inorganic sources (i.e. zinc oxide, zinc sulphate and zinc nitrate) of Zn for improving Zn uptake by salt tolerant wheat varieties in a pot trial. Whereas, in second experiment the effect of zinc sulfate (ZnSO4; inorganic) alone and in combination with sugarcane filter cake (SFC; organic) was evaluated in sustaining wheat growth under naturally salt affected soil. Results from pot trial suggested that among different organic sources, SFC application significantly enhanced the plant height (12.52%), spike length (9.07%) and number of fertile tillers (25%), whereas, application of ZnSO4 among the inorganic sources resulted in notable enhancements in plant height (7%), number of fertile tillers (24%), and spike length (8%) compared to their corresponding treatments. In addition, wheat variety Sehar-2006 proved to be the most efficient wheat variety under salinized conditions. Whereas the findings of the field trial revealed ZnSO4 application @ 24 kg ha-1 in combination with SFC 1 % w/w improved the plant height (2%), grain yield (81%), K+/Na+ ratio (1.4 fold), catalase (8%) and peroxidase (3%) activities. [ABSTRACT FROM AUTHOR]

Boron (B) is an essential element for higher plants with a widespread deficiency in agricultural soils. Salinity, another common agricultural problem, aggravates B toxicity in plants. NaCl salinity increases B toxicity symptoms on plants and soluble B concentration in inter- and intracellular compartments in leaves. In many cases salinity and high soil B occur together making the conditions more hostile for the plants e.g. the San Joaquin Valley, California. This study investigates the interactive effects of boron toxicity and different salts including NaCl, Na2SO4 and CaCl2. These three salts were used in three separate experiments and wheat plants were exposed for three weeks to either boron or a salt alone or in combination. Salinity x boron significantly reduced shoot as well as root growth of wheat irrespective of the salt used to develop salinity. Sodium sulphate salinity alone and in combination with boron caused a higher percent reduction in shoot fresh and dry weights followed by sodium chloride and calcium chloride salinity. It shows a differential interaction of these salts with boron that may be due to their differential effect on the uptake of boron or vice versa.

Soil salinity is considered a serious environmental issue in many countries of the world, including Pakistan. A hydroponic experiment was carried out to study different mechanisms of salinity tolerance in two Acacia species, namely Acacia stenophylla A. Cunn. ex Benth. and Acacia albida Delile. Uniform seedlings of both species were grown for 28 days in half-strength Hoagland's nutrient solution with 0, 100, or 200 mmol x [L.sup.-1] NaCl concentrations. The results revealed that shoot biomass decreased by 21% and 29% at the lower salinity level (100 mmol x [L.sup.-1] NaCl) and by 44% and 55% at the higher salinity level (200 mmol x [L.sup.-1] NaCl) in A. stenophylla and A. albida, respectively. The respective reductions in root biomass of both species were 20% and 29% at the lower salinity level and 36% and 54% at the higher salinity level. The physiological attributes such as chlorophyll and relative water contents decreased to a greater extent in A. albida than in A. stenophylla. As a result of oxidative stress, membrane stability index (MSI) decreased in both species, with a greater reduction in A. albida. Among different antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), the highest increase (sixfold) was observed in SOD activity in A. stenophylla. This study concludes that A. stenophylla is more salinity tolerant than A. albida as it maintained better ionic balance and higher activities of antioxidant enzymes and, as a result, higher biomass production. Key words: Acacia, CAT, MSI, [K.sup.+]: [Na.sup.+], salinity, SOD. La salinite du sol est consideree comme un probleme environnemental serieux dans plusieurs pays dans le monde incluant le Pakistan. Une experience en milieu hydroponique a ete realisee pour etudier les differents mecanismes de tolerance a la salinite chez deux especes d'Acacia : Acacia stenophylla A. Cunn. ex Benth. et Acacia albida Delile. Des semis uniformes des deux especes ont ete cultives pendant 28 jours dans une solution nutritive de Hoagland diluee de moitie contenant des concentrations de 0,100 ou 200 mmol x [L.sup.-1] de NaCl. Les resultats revelent que la biomasse des pousses a ete reduite de respectivement 21 et 29 % avec le niveau de salinite le plus faible (100 mmol x [L.sup.-1] de NaCl) et de 44 et 55 % avec le niveau de salinite le plus eleve (200 mmol x [L.sup.-1] de NaCl) chez A. stenophylla et A. albida. La reduction respective de la biomasse racinaire chez les deux especes etait de 20 et 29 % avec le niveau de salinite le plus faible et de 36 et 54 % avec le niveau de salinite le plus eleve. Les attributs physiologiques tels que le contenu en chlorophylle et la teneur relative en eau ont ete davantage reduits chez A. albida comparativement a A. stenophylla. A cause du stress oxydatif, l'indice de stabilite de la membrane (MSI) a ete reduit chez les deux especes quoique davantage chez A. albida. Parmi differentes enzymes antioxydantes telles que la superoxyde dismutase (SOD), laperoxydase (POD) et la catalase (CAT), la plus forte augmentation (six fois) a ete observee dans le cas de la SOD chez A. stenophylla. Sur la base de cette etude on peut conclure que A. stenophylla tolere mieux la salinite que A. albida etant donne qu'il maintenait une meilleure balance ionique et une plus grande activite des enzymes antioxydantes avec comme resultat une plus grande production de biomasse. [Traduit par la Redaction] Mots-cles: Acacia, CAT, MSI, [K.sup.+] : [Na.sup.+], salinite, SOD., Introduction Salinity is a global environmental problem, particularly in arid climatic regions of the world (Murtaza et al. 2011). Approximately 20% of the world's arable lands have high concentrations of [...]

Salinity is one of the major abiotic stresses that is deteriorating soil fertility and reducing essential nutrients acquisition by plants around the world. Among staple food, wheat can be a primary source of micronutrients like Fe and Zn. The saline/saline-sodic and calcareous soils are deficient in Fe and Zn. In these regards, the aim of present study was to screen out wheat genotypes which can efficiently utilize Fe and Zn in saline conditions. Therefore, ten wheat genotypes (i.e., Ujala-2016, Punjab-2011, Galaxy-2013, Faisalabad-2008, Anaj-2017, SARC-I, SARC-VIII, Lasani-2008, Sehar-2006 and Inqalab-91) were exposed to varying rates of Zn (0.2, 0.4 µM) and Fe (25, 50 µM) under saline and normal conditions in a solution culture experiment. Salinity was developed by using NaCl salt, while the sources of Zn and Fe were ZnSO4.7H2O and FeSO4.7H2O, respectively. The data of various wheat growth and ionic parameters including root/shoot dry weight, chlorophyll contents, Zn, Fe, K and Na concentration in root and shoot of wheat genotypes were recorded using standard procedures. The results showed that Fe and Zn application significantly (p ≤ 0.05) increased wheat plant growth under salt stress. Among tested genotypes, Faisalabad-2008 and Galaxy-2013 performed better under saline conditions with maximum biomass production, Zn, Fe and K absorption. Thus, these both genotypes were found to be good source for future wheat breeding programs or can be grown by farmers owing to efficient Fe and Zn utilization as a gateway toward the production of Fe and Zn biofortified wheat under saline conditions. [ABSTRACT FROM AUTHOR]

Salinity is a major environmental stress that is reducing crop yield, particularly in arid and semi-arid regions of the world. It is responsible for many physiological and biochemical disorders in plants. To investigate its effects on two acacia species, namely Acacia ampliceps Maslin and Acacia nilotica L., a solution-culture experiment was conducted in which both species were exposed to NaCl concentrations of 100 and 200 mmol x [L.sup.-1]. After four weeks of salinity stress, plants were harvested, and physical-growth data were recorded. The membrane stability index and activities of antioxidants enzymes such as superoxide dismutase, peroxidase, and catalase were determined using standard methods. Root exudates were collected for the analysis of organic acids, i.e., citric acid and tartaric acid. Root ash alkalinity was also measured. The results indicated that salinity stress caused a significant increase in the activities of antioxidant enzymes and in the release of organic acids in both species. Higher activities of antioxidant enzymes resulted in less damage to membranes and produced more shoot and root biomass in A. ampliceps than in A. nilotica. Likewise, having more rhizosphere acidification enabled A. ampliceps to respond in a better way to salinity stress than A. nilotica. Key words: salinity, ash alkalinity, citric acid, catalase, peroxidase. La salinite est un stress environnemental majeur qui reduit le rendement des cultures particulierement dans les regions arides et semi-arides du globe. Elle est responsable de plusieurs desordres physiologiques et biochimiques chez les plantes. Afin d'etudier ses effets sur deux especes d'acacia, a savoir Acacia ampliceps Maslin et A. nilotica L., une experience en milieu de culture liquide oU les deux especes ont ete exposees a des concentrations de 100 et 200 mmol x [L.sup.-1] de NaCl a ete realisee. Apres quatre semaines de stress salin, les plantes ont ete recoltees et des donnees de croissance ont ete notees. L'indice de stabilite membranaire et l'activite d'enzymes antioxydantes telles que la superoxyde dismutase, la peroxydase et la catalase ont ete mesures a l'aide de methodes standard. Des exsudats racinaires ont ete collectes pour l'analyse des acides organiques, c.-a-d. l'acide citrique et l'acide tartrique. L'alcalinite de la cendre de racine a aussi ete mesuree. Les resultats indiquent que la salinite cause une augmentation significative de l'activite des enzymes antioxydantes et la liberation d'acides organiques chez les deux especes. Avec l'augmentation de l'activite des enzymes antioxydantes il y avait moins de dommages aux membranes et une plus grande production de biomasse racinaire et caulinaire chez A. ampliceps que chez A. nilotica. De meme, l'acidification plus prononcee de la rhizosphere a permis a A. ampliceps de mieux reagir a la salinite que sa contrepartie. [Traduit par la Redaction] Mots-cles: salinite, alcalinite des cendres, acide citrique, catalase, peroxydase., Introduction Salinity is one of the major abiotic stresses and has a large impact on plant growth and productivity. It is estimated that 6% of the world's land and 30% [...]

The current experiment was conducted to assess the impact of different heavy metals (HMs) present in the air associate with fine dust particles on four plant species (Sorghum bicolor, Zea mays, Conocarpus lancifolius and Ficus carica) distributed at multiple locations of Faisalabad in Punjab, Pakistan in pots. The plant species were exposed to air pollution on four sites to explore their impact on morphological attributes and uptake of HMs (i.e., Cadmium, Chromium, Nickle, and lead) in selected plant species tissues. Results indicated that the plants at Sargodha Road showed the minimum roots, shoots and leaves fresh weight (-32%, -35% and -41%, respectively,) compared control site. The chlorophyll concentrations were reduced significantly in all the four plant species by 34%, 29%, 31% and 27% for S. bicolor, Zea mays, Conocarpus. lancifolius and Ficus carica, respectively, compared to control at Sargodha Road. The maximum HMs concentration i.e., Cd (0.09), Cr (0.36), Ni (0.69) and Pb (11.4) mg kg-t, respectively was found in the soil of S. bicolor growing pots at Sargodha Road. The bioaccumulation factor was also maximum in plants grown along Sargodha Road. This study shows that the urban dust led to the accumulation of metals in studied plant species, thereby posing potential threat of food chain contamination. [ABSTRACT FROM AUTHOR]