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Vanadium (V) is a multivalent redox-sensitive metal that is widely distributed in the environment. It enters the environment mainly through anthropogenic activities, such as industry, mining, fossil fuel burning, and fertilization, and imposes serious problems for plants, animals, and human health. The adverse effects of V on human health are determined by its movement through the environmental components (i.e., atmosphere, water, and soil). Exceeding the well-defined threshold level of V intake in animals (species-specific) and humans (V > 4500 µg per day) causes diseases such as vasoconstriction, congestion, focal hemorrhage in the lungs and adrenal cortex, congestion, fatty liver, and diarrhea, dehydration, cardiac disturbances, reduction in food intake, or weight loss. The threshold level of V toxicity varies from species to species. Low concentrations of V increased the root length, plant height, and biomass yield due to increased seed germination, chlorophyll, nutrient uptake, and nitrogen utilization. High concentrations of V inhibit protein synthesis, enzyme activities, and ion transport, resulting in stunted plant growth, shoot and root abnormalities, and even plant death. Various soil properties, including organic matter status, pH, calcium, phosphorus, aluminum, and iron (hydr) oxides, are the crucial determinants of V bioavailability and uptake by plants. Alteration in these properties could improve plant growth by inhibiting V uptake. Phytoremediation using microorganisms and organic amendments can be a feasible technique to remediate V-polluted soils. In this review, we concise an overview of V distribution in different environmental components and its impact on plants and human health. In addition, we also discussed the possible remedial approaches to eliminate as well as reduce the V concentration in soil.

Tomato is considered as a valuable vegetable crop all over the world. It prefers loose, well drained loamy soils rich in organic matter. In Pakistan, mostly soils are calcareous in nature. In calcareous soils, the production of tomato crop is low because of zinc deficiency. Therefore, current study was aimed to examine the potential of foliar application of zinc oxide in tomato cultivar Tiny Tim Cherry in calcareous soil conditions. In the current study, all the studied traits i.e. plant height, stem diameter, number of branches per plant, number of leaves, number of flowers per plant, fruit weight and yield per plant were significantly higher after foliar application of zinc oxide (30 ppm) and significantly lower in controlled treatment as compared to other treatments of zinc oxide. The maximum total soluble solids (TSS), chlorophyll A, chlorophyll B, vitamin C, flavonoids, carotenoids and phenolics were recorded in plants treated with 30 ppm of zinc oxide as compared to other treatments. However, the highest acidity was calculated in 10 ppm, while the lowest acidity was measured in 0 ppm (control). Conclusively, foliar application of Zn has potential to increase the nutritional components of tomato fruits.

In rainfed agriculture, the optimum use of fertilizers could not be achieved due to moisture constraint. In such areas where agriculture is rainfall dependent, foliar application of nutrients is better option to optimize crop yield. Therefore, the present study was conducted to check the performance of maize varieties and assess the effect of foliage applied potassium (K) on the photosynthetic activity, stay green, grain yield and related attributes of maize under rainfed condition. Current study was carried out with the objective to find best adopted variety and K rate for increasing photosynthetic activity and grain yield in maize. The results showed that, foliar application of K (2%) improved stomatal conductance, photosynthetic rate and chlorophyll contents in maize variety Islamabad gold. It also improved grain size and 1000-grain weight which leads to 10% higher grain yield compared with control. However foliar application of 2% K as well as maize variety Islamabad gold should be further investigated under rainfed condition.

Copper oxide (CuO) nanostructures are synthesized via a simple and novel atmospheric pressure microplasma technique without using any surfactant. The effect of electrolyte concentration on structure, size, and morphology of CuO nanostructures has been investigated by X-ray diffraction (XRD), laser-induced breakdown spectroscopy (LIBS), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results revealed the formation of highly crystalline single phase CuO, exhibiting a monoclinic structure. SEM images have shown an interpenetrating self-assembled nanosheets (NS) with varying sizes. The energy bandgap of the samples is estimated between 2.0 and 2.73 eV. The antibacterial activity of CuO NS demonstrates significant bactericidal efficiency against gram-negative bacteria. In addition, these NS are checked for the degradation of organic dyes such as Rhodamine B and methyl orange under sunlight irradiation which showed significant degradation, indicating excellent photocatalytic activity. It has been found that CuO NS are promising material for pharmaceutical and biomedical applications because of its attractive photocatalytic and antibacterial properties.

Vanadium (V) as minor concentration is present in various plants and extensively found in soils. The current study was established to assess the response of rice seedlings to different V concentrations and also investigated its toxic effect on growth, photosynthetic assimilation, relative chlorophyll content, SPAD index, ion leakage, enzyme activities, hydrogen peroxide (H2O2), and cell death. The rice seeds were sown in Petri dishes for 8 days, and after that, rice seedlings were grown hydroponically in a climate-controlled growth chamber. After 15 days of V-treatment, antioxidant enzyme activities, H2O2, protein contents, photosynthetic assimilation, relative chlorophyll content, and cell death were determined by utilizing the Spectrophotometer (Lambda 25 UV/VIS Spectrophotometer), and V accumulation (roots and shoots) was determined by GFAAS (GTA 120). The obtained results showed that all V concentrations significantly decreased the biomass (dry and fresh) and root growth as a result of the reduction in total root length, root tips, root fork, root surface area, and root crossing, and V was more accumulated in roots than shoots. Besides this, enzymatic activities were significantly enhanced under V stress. The findings also confirmed that seedling exposed to V stress had lower tolerance indices, photosynthetic activity, and protein contents while the ion leakage was consistently increased by increasing the V concentrations. The viability of plant cells severely damaged in response to high V stress, and H2O2 induction might be responsible for cell death. Generally, all V doses had a drastic effect on enzyme activities and caused cell death of rice plans. Moreover, the current study demonstrated that V ≥ 35 mg L−1 caused damaging effects on rice plants.

Lipoic acid (LA) and melatonin (MT) are pleiotropic molecules participating in plant stress resistance by modulating cellular biochemical changes, ion homeostasis, and antioxidant enzyme activities. However, the combined role of these two molecules in counteracting the detrimental impacts of salinity stress is still unknown. In the present study, we determined the effects of exogenous LA (0.5 µM), MT (1 µM) and their combination (LA + MT) on growth performance and biomass accumulation, photosynthetic pigments, enzymatic and non-enzymatic antioxidant activities, and ions homeostatic in canola (Brassica napus L.) seedlings under salinity stress (0, 100 mM) for 40 days. The results indicate that exogenous application of LA + MT improved the phenotypic growth (by 25 to 45%), root thickness (by 68%), number of later lateral roots (by 52%), root viability (by 44%), and root length (by 50%) under salinity stress. Moreover, total soluble protein, chlorophyll pigments, the concentration of superoxide dismutase (SOD), catalase peroxidase (CAT), and ascorbic peroxidase (ASA) increased with the presence of salt concentration into the growth media and then decreased with the addition of LA + MT to saline solution. Leaf protein contents and the degradation of photosynthetic pigments were lower when LA + MT treatments were added into NaCl media. The proline and phenol contents decreased in the exogenous application of LA + MT treatments more than individual LA or MT treatments under the salinity stress. The incorporation of LA or MT or a combination of LA + MT to saline solution decreased salinity-induced malondialdehyde and electrolyte leakage. In conclusion, the alteration of metabolic pathways, redox modulation, and ions homeostasis in plant tissues by the combined LA and MT application are helpful towards the adaptation of Brassica napus L. seedlings in a saline environment. The results of this study provide, for the first time, conclusive evidence about the protective role of exogenous LA + MT in canola seedlings under salinity stress.

Changing climates and frequent spells of drought have increased the risk of crop failure, especially in arid and semi-arid regions, thus multiplying the vulnerability of food-insecure populations. The exogenous application of potassium (K) can potentially ameliorate the adverse effects of drought in maize by maintaining cell osmotic potential and turgidity, provided its optimum doses are applied. The present experiment comprised two maize cultivars, viz. Islamabad Gold (drought tolerant) and Azam (drought susceptible), grown under well-watered (80% water-holding capacity (WHC)), mild drought (60% WHC) and severe drought (40% WHC) conditions. Different doses of K, viz. 0%, 1% and 2%, were also tested to screen out the most superior concentration. Drought stress markedly reduced root and shoot lengths (25% and 16%, respectively) along with their dry weights (20% and 10%, respectively). Moreover, a substantial reduction in leaf relative water content (RWC) (24%), stomatal conductance, transpiration and photosynthesis rates, chlorophyll pigments a, b and total chlorophyll contents (31%) were recorded, compared with well-watered conditions. However, foliar application of K2SO4 at 2% concentration outperformed other doses by improving growth attributes, RWC (10%), total chlorophyll (9%) and proline (12%) under severe drought conditions. Our findings confirmed the effectiveness of foliage-applied K2SO4 in ameliorating drought effects in rainfed maize, however, more doses and sources of K could be tested for developing it as a potent source to cope with water stress.

Boron (B) is deficient in the calcareous, Typic Haplocambid soils of cotton growing belt of Pakistan, and thus is a vital reason for less cotton yield in the region. In order to investigate the growth and quality alterations associated with soil applied B on cotton (cv. CIM-616 and CIM-600) an experiment was conducted. Boron was applied at 0.00, 2.60, 5.52, 7.78 and 10.04 mg B kg−1 of soil using borax (Na2B4O7.10H2O), in a complete randomized design with factorial arrangement with four replications. Results revealed that soil applied B @ 2.60 mg B kg−1 of soil significantly (P≤0.05) improved cotton growth, yield, quality and B distribution among different parts. Different growth and yield parameters like plant height, leaf area, number of bolls, boll size and weight, seed cotton yield, photosynthesis, transpiration rate, stomatal conductance, water use efficiency, GOT, staple length and fiber fineness and strength except B uptake by roots, seed, leaves and stalk plant body which was significantly increased with B (10.04 mg B kg−1) in both cultivars of cotton, but the degree of effects was varied between cultivars. The results indicated that studied traits of both cultivars were significantly (P≤0.05) decreased in B-deficient stressed treatments. Between hybrids, CIM-600 produced significantly (P≤0.05) maximum recorded parameters under 2.60 mg B kg−1 application compared than CIM-616. Our findings confirm that the adequate level of B (2.60 mg B kg−1) had pronounced effects on various growth, yield, physiological and fiber quality associated traits, as compared to B uptake traits of cotton cultivars.

Boron (B) is required during all growth stages of cotton crop, especially during boll formation. However, Typic Haplocambid soils of cotton growing belt in Pakistan are B-deficient, which results in low yield and economic returns. Foliar application of B improves cotton productivity; however, information is limited on the role of soil applied B in improving cotton growth and yield. The current study investigated the role of soil applied B in improving growth, yield and fiber quality of cotton crop. Five different B doses (i.e., 0.00, 2.60, 5.52, 7.78 and 10.04 mg kg-1 of soil) and two cotton cultivars (i.e., CIM-600 and CIM-616) were included in the study. Soil applied B (2.60 mg kg-1) significantly improved growth, yield, physiological parameters and fiber quality, while 10.04 mg kg-1 application improved B distribution in roots, seeds, leaves and stalks. Significant improvement was noted in plant height (12%), leaf area (3%), number of bolls (48%), boll size (59%), boll weight (52%), seed cotton yield (52%), photosynthesis (50%), transpiration rate (10%), stomatal conductance (37%) and water use efficiency (44%) of CIM-600 with 2.60 mg kg-1 compared to control treatment of CIM-616. Similarly, B accumulation in roots, seeds, leaves and stalk of CIM-600 was improved by 76, 41, 86 and 70%, respectively compared to control treatment. The application of 2.60 mg kg-1 significantly improved ginning out turn (6%), staple length (3.5%), fiber fineness (17%) and fiber strength (5%) than no B application. The results indicated that cultivar CIM-600 had higher ginning out turn (1.5%), staple length (5.4%), fiber fineness (15.5%) and fiber strength (1.8%) than CIM-616. In crux, 2.60 mg kg-1 soil B application improved growth, yield, physiological and fiber quality traits of cotton cultivar CIM-600. Therefore, cultivar CIM-600 and 2.60 mg kg-1 soil B application is recommended for higher yield and productivity.

Freshwater alternatives to irrigate crops are in dire need of time because of changing climate and scarcity of freshwater. Therefore, seawater can be the best feasible option as it is abundantly available on Earth. Sole application of seawater for agricultural crops is impossible, but the blend with freshwater may not be aggravating the salinization problems in soils. The present investigation was conducted to evaluate the possibility of growing the short period summer vegetables i.e., eggplants, tomato, and pepper with fresh and seawater blends viz. 5%, 10% and 20%, termed as A, B and C treatments, respectively. During the experiment, we considered: (i) crop growth, biomass yield, water consumption, water use efficiency (WUE) and water productivity (WP), (ii) photosynthetic pigments and gas exchange parameters, (iii) concentration of mineral contents and quality traits, (iv) lipid peroxidation, proline contents and ascorbic acid. Tomato productivity was markedly decreased by application of B and C treatments, whereas the growth of eggplant and pepper were not much influenced at the same concentrations. Water consumption dropped, whereas WUE significantly increased in all tested crops upon increasing seawater concentrations. Leaf Na+ concentration and other mineral elements increased. These results assumed that certain concentrations of seawater–freshwater blends revealed that there were no significant effects on the quality characteristics, mineral elements concentration and productivity of eggplant and pepper plants, however, tomato plants indicated sensitivity at the three seawater concentrations (A, B and C SFW treatments). Moreover, low concentrations of salinity stress (5% and 10% SFW) seemed to be necessary to attain better crop nutrition and organoleptic values. Accordingly, the results of present will be helpful to coastline farmers in cultivating vegetables and produce nutritive food for their family.

Drought stress creates imbalance or deficiency of some growth regulators in plants, which leads toward reduced crop yield. Gibberellic acid is one of the most important growth regulators in plants, which improve drought tolerance in plants under optimum concentration. A field experiment was conducted under exogenous application of gibberellic acid under normal or drought condition and with or without gibberellic acid application. Crop growth and yield parameters were assesses during the experimentation. Study revealed that crop reduced growth in term of leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), net assimilation rate (NAR) and total dry matter (TDM) under drought condition, while these parameters were improved with gibberellic acid application. Similary, improved growth rate resulted in better performance of yield attributes (cob length, cob diameter, grains per cob, grain weight and yield). Gibberellic acid application improved the crop performance at optimum irrigation, as well as under reduced irrigation. Although highest crop yield was recorded with gibberellic acid application under optimum irrigation level, while its application under drought stress improved crop tolerance and resulted in better crop yield, similar to optimum irrigation level. Exogenous application of gibberellic acid not only improved the drought tolerance in maize, but also increased the crop yield under normal condition.

Boron (B) is one of the essential micronutrients having a specific role, particularly during reproductive phase, in rice. In a previous experiment on aerobic rice, panicle sterility was noted as one of the major challenges. This experiment was conducted to evaluate the influence of soil-applied B on tillering, panicle sterility, water relations, and grain enrichment in fine-grain aromatic rice cultivars ‘Super Basmati’ and ‘Shaheen Basmati’. Boron was soil applied at 0.50, 0.75, 1, 1.25, and 1.50 kg ha−1 while the control treatment did not receive B. Rate of leaf emergence and elongation and tiller appearance were significantly improved by B application. Likewise, B application also improved the leaf chlorophyll contents and water relations in both rice cultivars. Substantial improvement in kernel yield and yield contributing traits was also observed by B application owing to decrease in panicle sterility. A linear increase in leaf and kernel B contents was observed with increase in B application rate. Ho...

Boron (B) deficiency is becoming a common problem in water-saving rice production systems of South Asia. Boron nutrition can potentially improve the crop performance. This two-year field study was conducted to evaluate the potential of pre-optimized B application through various methods in improving the performance of rice grown in aerobic culture, alternate wetting and drying and flooded systems. Boron was delivered as seed priming (0.1 mM B), foliar spray (200 mM B), and soil application (1 kg B ha−1); no B application and hydropriming were taken as control. Boron nutrition by either method improved the plant water relations, total chlorophyll contents, morphological and yield related traits in different rice production systems. In addition to improvement in kernel yield, boron application also improved the kernel quality. Foliar application of boron in flooded rice and alternate wetting and drying gave maximum net returns than all other treatment combinations. In crux, B application through foliar spary or seed priming may be an economically viable option to reduce panicle sterility, improve kernel quality, rice growth and yield. Improvement in rice yield by B application is attributed to increase in kernel size and decrease in panicle sterility.

Unavailability of balanced nutrients in nutrient-deficient soils is the key reason in reduced yields of spring maize. After application to soil, most of the phosphorus (80&ndash, 90%) is lost in the environment because of runoff losses and chemically bonding. So, this makes the phosphorus unavailable for plant use. However, soil microorganisms may provide a biological rescue system which is able to solubilize the soil-bound phosphorus (p). Keeping this in view, the present study is designed to meet the following objectives, (1) to improve physico-chemical properties of soil (e.g., soil water retention, soil enzyme activities), and (2) to improve growth and yield of spring maize (cv. Hybrid YSM-112) through the inoculation of phosphorus solubilization bacteria (PSB). A pot experiment was carried out with the following treatments, T1: control (uninoculated control, CT), T2: inoculation with PSB (Enterobacter sakazakii J129), T3: recommend level of NPK fertilizers (RNPK), T4: PSB + RNPK fertilizers, T5: rock phosphate (RP), T6: PSB + RP. Results showed that the addition of PSB together with RNPK improved the yield and yield-related characteristics of spring maize grown in sandy soil. Moreover, it also enhanced dry mater characteristics and maize grain quality. Soil fertility in the context of P-solubilization, soil organic acids, soil organic matter, enzyme activities, PSB colony, and rhizosphere moisture contents were significantly improved with PSB inoculation together with recommended dose of NPK fertilizers (RNPK) compared to PSB alone, rock phosphate (RP) alone, or PSB together with rock phosphate and control treatment. Maize digestibility attributes such as DM, CP, CF, EE (by 35%, 20%, 33%, and 28% respectively) and grain quality such as NPK, Mg, Ca, Fe, Mn, Cu, and Zn (by 88%, 92%, 71%, 68%, 78%, 90%, 83, 69%, 92%, 48%, and 90% respectively) were improved compared to control. In conclusion, improvement in maize crop yield and soil characteristics are more prominent and significant when RNPK is supplemented and inoculated. The present study suggests that PSB, together with RNPK, would improve the maize plant growth and soil fertility in sandy soil.

This study was conducted to explore the role of boron (B) in seedling emergence, leaf elongation, and tillering dynamics. Boron was applied as seed priming. For priming seeds of two rice cultivars (Super Basmati and Shaheen Basmati) were soaked in B solutions having 0.001, 0.01, 0.1 and 0.5% concentrations. Substantial improvement in seedling emergence was observed from hydropriming and seed priming in 0.001 and 0.01% solutions; beyond this B concentration, emergence potential was suppressed. Seeds primed in 0.5% B solution even did not emerge. A linear increase in plant height was recorded up to 30 days from seeds primed in 0.001% solution. Similarly rate of leaf emergence and elongation and rate of tiller appearance were substantially improved in seedlings raised from seeds primed in 0.001% B solution. Overall B plays a significant role in leaf appearance, elongation and tillering dynamics of rice when used in very low concentration.

Boron (B) is amongst the important micronutrients required for rice from start till physiological maturity. This study was conducted to explore the role of boron application in seedling emergence, leaf appearance and elongation, chlorophyll content, water relations and yield related traits of fine rice. Boron was applied as seed priming. For priming seeds of fine rice cultivars Super Basmati and Shaheen Basmati were soaked in 0.001 and 0.01 % aerated B solutions (w/v); while untreated dry seeds and water soaked (hydropriming) seeds were taken as control. Substantial improvement in seedling emergence was noted by seed priming in 0.001 and 0.01 % solutions. Rate of leaf emergence and elongation and tiller appearance were also improved in seedlings raised from seeds primed in 0.001 % B solution in the tested cultivars. Likewise, leaf chlorophyll contents were significantly improved by B especially with 0.001 % concentration; as was the case for water relations of rice cultivars. At final harvest, all yield contributing parameters were improved by B priming. Increase in yield was due to decrease in panicle sterility by B treatments. A linear increase in leaf and grain B contents was observed with increase in concentration of B priming solution. Overall, B application at very low rate substantially improved seedling emergence, leaf appearance and elongation, tillering, chlorophyll, water relations and yield related traits resulting in better yield and grain B contents. In this regard, seed priming offers an effective and pragmatic way of B application.

This study was conducted to investigate the benefits associated with re-drying after seed priming with polyamines. Wheat (cv. AS-2002) seeds were soaked in 10 and 20 mg L−1 aerated solutions of spermidine (Spd), putrescine (Put) and spermine (Spm), and distilled water (CK2) for 12 h at 28 ± 2°C. Untreated seeds (CK1) and priming in distilled water (CK2) were taken as control treatments. Seeds were primed in two sets: In one set, after each treatment, seeds were given three surface washings with distilled water and dried closer to original moisture; in the other, seeds were only surface dried and used immediately. Use of surface-dried seeds after priming was more effective since it reduced emergence time and synchronized the emergence. Moreover, final emergence, shoot and root length, seedling fresh and dry weight were also improved. Improved starch metabolism was considered possible reason of seed invigoration. All the seed treatments resulted in a lower electrical conductivity of seed leachates compared with control; however, there was more decrease in seeds re-dried after priming than the seeds surface dried after priming. Although the effect of all the polyamines was stimulatory, Spd was the more effective for most of the attributes studied. Nonetheless, Put was more effective for seedling fresh and dry weights. All the polyamines were more effective at lower concentrations except Spm, which improved the coefficient of uniformity of emergence at high concentration. To conclude, if immediate sowing is possible, use of surface-dried seeds after priming may be more effective; seed priming with 10 mg L−1 Spd was the most effective technique when surface dried.

This study was conducted to evaluate the influence of boron (B) application through seed coating on leaf elongation, tillering, water relations, panicle sterility, kernel yield, and grain biofortification of fine grain aromatic rice. Boron was applied as seed coating at 1.0, 1.5, 2.0, 2.5, and 3.0 g B kg−1 seed in two rice cultivars Super Basmati and Shaheen Basmati. Boron seed coating significantly affected the leaf elongation, water relations, panicle fertility, kernel yield and grain biofortification in both rice cultivars. However, seed coating with 1.0–2.0 g B kg−1 seed was effective in improving the leaf emergence and elongation, and tillering. Whereas water relations (water and osmotic potential) were improved by all B seed coating treatments, but pressure potential was only improved from seed coating with 2.0–3.0 g B kg−1 seed. Kernel yield was improved by all B seed coating treatments; however seed coating with 2 g B kg−1 seed was the most effective treatment in this regard. Increase in kernel yield, by B seed coating, was attributed to decrease in panicle sterility. Leaf and kernel B contents were increased with increase in B concentration in seed coating.