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Arsenic (As) toxicity is a serious hazard to agricultural land due to growing industrialization, which has a negative effect on wheat crop yields. To address this issue, using seaweed extract and Azospirillum brasilense has emerged as an effective strategy for improving yield under stress conditions. However, the combined application of A. brasilense and seaweed extract in wheat crops under As toxicity has not been fully explored. The effectiveness of combining A. brasilense and seaweed extract in reducing As toxicity in wheat production was examined in this study through a 2-year pot experiment with nine treatments. These treatments included a control with no additives and two As concentrations (50 and 70 μM). At 50 and 70 μM, As was tested alone, with seaweed extract, with A. brasilense, and both. Significant results were achieved in reducing As toxicity in wheat crops. Arsenic at 70 μM proved more harmful than at 50 μM. The application of A. brasilense and seaweed extract was more effective in improving crop growth rates, chlorophyll levels, and stomatal conductance. The combined application notably decreased As concentration in wheat plants. It was concluded that applying A. brasilense and seaweed extract not only improves wheat growth but can also improve soil parameters under As toxicity conditions by increasing organic matter contents, boosting nutrient availability, and increasing the production of antioxidant enzymes. [ABSTRACT FROM AUTHOR]

Potato farming is a vital component of food security and the economic stability especially in the under developing countries but it faces many challenges in production, blackleg disease caused by Pectobacterium atrosepticum (Pa) is one of the main reason for damaging crop yield of the potato. Effective management strategies are essential to control these losses and to get sustainable potato crop yield. This study was focused on characterizing the Pa and the investigating new chemical options for its management. The research was involved a systematic survey across the three district of Punjab, Pakistan (Khanewal, Okara, and Multan) to collect samples exhibiting the black leg symptoms. These samples were analyzed in the laboratory where gram-negative bacteria were isolated and identified through biochemical and pathogenicity tests for Pa. DNA sequencing further confirmed these isolates of Pa strains. Six different chemicals were tested to control blackleg problem in both vitro and vivo at different concentrations. In vitro experiment, Cordate demonstrated the highest efficacy with a maximum inhibition zones of 17.139 mm, followed by Air One (13.778 mm), Profiler (10.167 mm), Blue Copper (7.7778 mm), Spot Fix (7.6689 mm), and Strider (7.0667 mm). In vivo, Cordate maintained its effectiveness with the lowest disease incidence of 14.76%, followed by Blue Copper (17.49%), Air One (16.98%), Spot Fix (20.67%), Profiler (21.45%), Strider (24.99%), and the control group (43.00%). The results highlight Cordate's potential as a most effective chemical against Pa, offering promising role for managing blackleg disease in potato and to improve overall productivity. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa) faces challenges to yield and quality due to urbanisation, deforestation and climate change, which has exacerbated high night temperature (HNT). This review explores the impacts of HNT on the physiological, molecular and agronomic aspects of rice growth. Rise in minimum temperature threatens a potential 41% reduction in rice yield by 2100. HNT disrupts rice growth stages, causing reduced seed germination, biomass, spikelet sterility and poor grain development. Recent findings indicate a 4.4% yield decline for every 1°C increase beyond 27°C, with japonica ecotypes exhibiting higher sensitivity than indica. We examine the relationships between elevated CO2, nitrogen regimes and HNT, showing that the complexity of balancing positive CO2 effects on biomass with HNT challenges. Nitrogen enrichment proves crucial during the vegetative stage but causes disruption to reproductive stages, affecting grain yield and starch synthesis. Additionally, we elucidate the impact of HNT on plant respiration, emphasising mitochondrial respiration, photorespiration and antioxidant responses. Genomic techniques, including CRISPR-Cas9, offer potential for manipulating genes for HNT tolerance. Plant hormones and carbohydrate enzymatic activities are explored, revealing their intricate roles in spikelet fertility, grain size and starch metabolism under HNT. Gaps in understanding genetic factors influencing heat tolerance and potential trade-offs associated with hormone applications remain. The importance of interdisciplinary collaboration is needed to provide a holistic approach. Research priorities include the study of regulatory mechanisms, post-anthesis effects, cumulative HNT exposure and the interaction between climate variability and HNT impact to provide a research direction to enhance rice resilience in a changing climate. We explore the impact of high night temperature (HNT) on rice phenomics, physiology and grain yield. From accelerated vegetative growth to changes in reproductive phases and enzymatic activities, we review how HNT affects rice in elevated CO2 and nitrogen environments to provide insights into photosynthesis, respiration and hormonal regulation, and their effect on grain yield and quality. This article belongs to the Collection Functional Genomics for Developing Climate Resilient Crops. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing concern regarding the impact of pesticide exposure on pollinators, particularly honeybees (Apis mellifera L.). This concern arises from their crucial role in maintaining ecological balance and global food production. Therefore, an extensive investigation has been conducted to explore the intricate relationship between pesticides and the biological development of honey bees in the Rahim Yar Khan region. This study assessed the impact of four pesticides (Emamectin benzoate, Chlorpyrifos, Imidacloprid, and Acetamiprid) on honey bee eggs, larvae, and adult bees under controlled laboratory conditions. The pesticides were applied at concentrations of 10%, 30%, and 50%, as per regional agricultural recommendations. A zero-toxicity control was also included for comparison. Toxicity evaluations were conducted through contact exposure, and Probit and regression analyses were performed using SPSS software to comprehensively assess the toxicity profiles. The study revealed significant adverse effects on the immediate behavioral responses of A. mellifera following pesticide exposure. These effects included heightened agitation, narcotic-like symptoms, audible hovering, crawling, ceased food-sharing behavior, and reduced proboscis extension. Chlorpyrifos exhibited the highest toxicity against adult bees, while Emamectin Benzoate had the least toxicity. Regarding honey bee eggs, Chlorpyrifos, Imidacloprid, and Acetamiprid were notably more toxic, whereas Emamectin Benzoate exhibited the least toxicity. The impact on larvae varied across developmental stages and pesticides, with Imidacloprid, Chlorpyrifos, and Acetamiprid causing significant mortality, while Emamectin Benzoate showed lower toxicity. The study highlights that Emamectin Benzoate demonstrates lower toxicity compared to other insecticides. This emphasizes the importance of balancing effective pest management with the preservation of pollinator health. The findings underscore the need for informed and sustainable approaches to pesticide use, taking into consideration the potential repercussions on honeybee development and behavior. [ABSTRACT FROM AUTHOR]

Water management techniques are improving at the farm level, but they are not enough to deal with the limited availability of water and increased crop yields. Soil microbes play a vital role in nitrogen fixation, improving soil fertility and enhancing plant growth hormones under drought conditions. Therefore, this study was conducted to investigate the impact of water management combined with Azospirillum brasilense and Rhizobium pisi on wheat crop productivity and soil properties in dry regions. Three water management techniques were compared, normal irrigation as a control (C), deficit irrigation (DI), and partial root drying irrigation (PRD), together with the interaction of plant-growth-promoting rhizobacteria (PGPR). Experiments were conducted with six treatments in total: T1 = C + No PGPR, T2 = C + PGPR, T3 = DI + No PGPR, T4 = DI + PGPR, T5 = PRD + No PGPR, and T6 = PRD + PGPR. The highest grain yield was achieved in the control irrigation treatment using seeds inoculated with rhizobacteria, followed by control treatment without any inoculation, and the lowest was recorded with deficit irrigation without rhizobacteria inoculated in the seeds. However, PRD irrigation resulted in significantly higher plant growth and grain yield than the DI treatment. PGPR inoculation combined with PRD resulted in a 22% and 20% higher number of grains per spike, a 19% and 21% higher grain yield, and a 25% and 22% higher crop growth rate compared to rhizobacteria inoculation combined with the DI system in 2021-22 and 2022-23, respectively. This increase was due to the higher production of growth hormones and higher leaf area index under water-limited conditions. A greater leaf area index leads to a higher chlorophyll content and higher food production for plant growth. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) pollution is a growing environmental problem that negatively impacts plant growth and development, particularly in maize. In this research, the impact of farmyard manure (FYM) and salicylic acid (SA) on rhizospheric characteristics and the reduction of Cd stress in maize was examined at Government College (GC) University, Lahore, in 2022. The experiment was arranged with a randomized design, including three replications of 12 treatments (T1 = Control; T2 = Farmyard manure; T3 = Salicylic Acid; T4 = 100 mg/kg of soil Cd; T5 = 200 mg/kg of soil Cd; T6 = Farmyard manure + Salicylic acid; T7 = FYM + 100 mg/kg soil Cd; T8 = FYM + 200 mg/kg soil Cd; T9 = SA + 100 mg/kg soil Cd; T10 = SA + 200 mg/kg soil Cd; T11 = FYM + SA + 100 mg/kg soil Cd; T12 = FYM + SA + 200 mg/kg soil Cd). Results demonstrated that Cd stress negatively affected the maize plant and soil properties, but the application of SA and FYM was effective to mitigate the Cd stress up to a certain level. A reduction of 41.52%, 39.14%, and 39.94% in root length, length of the leaf, and crop growth rate was noticed, due to the Cd stress at 200 mg/kg soil, but this reduction was reduced to 18.83%, 10.35%, and 12.26%, respectively, when FYM and salicylic acid were applied as a combined application under the same stress level of Cd. The root biomass, leaf surface area, and length were all improved by SA and FYM, which enhanced the plant's capacity to absorb nutrients and improve growth under Cd stress. In conclusion, the use of salicylic acid together with farm manure can be an effective approach to mitigate Cd stress in maize crops. [ABSTRACT FROM AUTHOR]

Wastewater from tanneries is a major source of heavy metals in soil and plants when used for crop irrigation. The unavoidable toxicological effects of this contamination, however, can be minimized through two independent steps discussed in the present study. In the first step, a batch sorption experiment was conducted in which Cr was adsorbed through bentonite clay. For this purpose, DTPA extraction method was used to analyze Cr concentration in the soil after regular time intervals (0.5, 1, 2, 6, 8, 9, 10.5, 11.5, and 20.3 h) which reduced Cr concentration from 38.542 mgL-1 for 30 min to 5.6597 mgL-1 for 20.3 h, respectively, by applying 1% bentonite. An increase in the contact time efficiently allowed soil adsorbent to adsorb maximum Cr from soil samples. In the second step, a pot experiment was conducted with 10 different treatments to improve the physiological and biochemical parameters of the Solanum melongena L. irrigated under tanneries' wastewater stress. There were four replicates, and the crop was harvested after 30 days of germination. It was seen that the application of wastewater significantly (P < 0.01) reduced growth of Solanum melongena L. by reducing root (77%) and shoot (63%) fresh weight when compared with CFOP (Ce-doped Fe2O3 nanoparticles); chlorophyll a and b (fourfolds) were improved under CFOP application relative to control (CN). However, the deleterious effects of Cr (86%) and Pb (90%) were significantly decreased in shoot through CFOP application relative to CN. Moreover, oxidative damage induced by the tannery's wastewater stress (P < 0.01) was tolerated by applying different soil amendments. However, results were well pronounced with the application of CFOP which competitively decreased the concentrations of MDA (95%), H2O2 (89%), and CMP (85%) by efficiently triggering the activities of antioxidant defense mechanisms such as APX (threefold), CAT (twofold), and phenolics (75%) in stem relative to CN. Consequently, all the applied amendments (BN, BT, FOP, and CFOP) have shown the ability to efficiently tolerate the tannery's wastewater stress; results were more pronounced with the addition of CFOP and FOP+BT by improving physiological and biochemical parameters of Solanum melongena L. in an eco-friendly way. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria are known to associate with several cereal crops. The rhizobacterium exerts its function by synthesizing diverse arrays of phytohormones, such as cytokinin (Ck). However, it is difficult to determine the plant growth promotion when a bacterium produces many different kinds of phytohormones. Therefore, to assess the involvement of Ck in growth promotion and activation of antioxidant and physiological systems, we set up this experiment. Wheat seeds (Triticum aestivum L.) were inoculated with Azospirillum brasilense RA−17 (which produces zeatin type Ck) and RA−18 (which failed to produce Ck). Results showed that seed inoculation with RA−17 significantly improved growth and yield-related parameters compared with RA−18. The activity of enzymes, proline contents, and endogenous hormonal levels in wheat kernels were improved considerably with RA−17 than with RA−18. Strain RA−17 enhanced grain assimilation more than strain RA−18 resulting in a higher crop yield. These results suggest that microbial Ck production may be necessary for stimulating plant growth promotion and activating antioxidant and physiological systems in wheat. [ABSTRACT FROM AUTHOR]

Biofertiliser is considered a promising biofortification intervention that can integrate with plant breeding as well as agronomic measures to overcome malnutrition in regions where the staple diet is cereal. This study was conducted to improve maize (Zea mays L.) productivity and biofortification with zinc (Zn) through the application of Zn-solubilising biofertilisers. Four pre-isolated, promising Zn-solubilising Bacillus strains, Bacillus sp. ZM20, B. aryabhattai ZM31, B. aryabhattai S10 and B. subtilis ZM63, were coated on maize seeds by forming slurry-based sole- and co-inoculated biofertilisers. The treated maize seeds were grown in a spring season (Trial I) and the experiment was repeated the following year on the same field (Trial II). The seed-applied co-inoculated Bacillus biofertiliser formulations significantly promoted antioxidant enzyme activities (ascorbate peroxidase, peroxidase and superoxide dismutase), growth and yield attributes, and nutrient accumulation in maize grains during both field trials compared with sole-inoculated biofertiliser formulations. Application of ZM31–ZM63 biofertiliser formulation showed a greater increase in these attributes than other biofertiliser formulations, as well as an increase in grain iron (Fe) concentration (up to 1.69-fold in Trial I and 1.77-fold in Trial II) and Zn concentration (up to 1.50-fold in Trial I and 1.41-fold in Trial II) relative to the uninoculated control. Fe and Zn concentrations in maize grains resulting from the application of seed-based Bacillus biofertiliser formulations could fulfill the minimum required level of these nutrients for daily intake. From the study, recommendation can be made to apply Zn-solubilising bioinoculants for the biofortification of maize grains to overcome malnutrition issues in regions with cereal-based staple diets. Plant growth-promoting bacteria are considered a possible promising biofortification intervention to address micronutrient malnutrition. Seed-applied zinc-solubilising Bacillus biofertiliser improved antioxidant enzyme activities and growth and yield attributes of maize, and biofortified maize grains under field conditions. Micronutrient biofortification in maize grains via biofertiliser application could be implemented to overcome malnutrition issues in regions with cereal-based staple diets. [ABSTRACT FROM AUTHOR]

In order to meet the dietary requirements of the rising human population with diminishing water resources, there is the need to adopt techniques that optimize crop yield under reduced water conditions. Therefore, a greenhouse experiment was carried out to determine the effect of mulching and reduced irrigation on wheat production. The experiment included four mulching treatments (un-mulched, black plastic sheet mulch, wheat straw mulch and cotton sticks mulch) and two watering regimes (normal watering and partial root-zone drying irrigation (PRI) technique that involves alternate watering to only one side of root zone only) arranged in a completely randomized design. Wheat growth (leaf area index, plant height), water related parameters (leaf relative water contents (RWC), leaf turgor potential and physiological (chlorophyll contents, stomatal oscillation and photosynthetic rate) parameters and biochemical indicators were significantly higher with mulching than un-mulched for both irrigation levels. However, among the mulching treatments, the use of black plastic mulch gave the best results. Among the mulch treatments, RWC increased by 4.29%, 7.50% and 10.73% with black plastic mulch compared to wheat straw mulch, cotton stick mulch and control treatment, respectively. Between the two irrigation levels, higher wheat growth, physiological and water related parameters were found with full irrigation. Whereas leaf osmotic potential, quality traits and antioxidant enzymatic activities were higher with PRI. This study shows that, particularly with black plastic film, mulching combined with partial root zone drying can be effectively used in conserving soil water, thus increasing crop water use, photosynthetic rate, and yield. [ABSTRACT FROM AUTHOR]

Different soil amendments are applied to improve soil properties and to achieve higher crop yield under drought conditions. The objective of the study was to investigate the role of biochar for the improvement of wheat (Triticum aestivum L.) growth and soil biochemical properties under drought conditions. A pot experiment with a completely randomized design was arranged with four replications in a wire house. Drought was imposed on two critical growth stages (tillering and grain filling) and biochar was applied to the soil 10 days before sowing at two different rates (28 g kg-1 38 g kg-1 Soil samples were collected to determine the soil properties including soil respiration and enzymatic parameters after crop harvesting. Results showed that water stress negatively affects all biochemical properties of the soil, while biochar amendments positively improved these properties. Application of biochar at 38 g kg-1 provided significantly higher mineral nutrients, Bray P (18.72%), exchangeable-K (7.44%), soil carbon (11.86%), nitrogen mineralization (16.35%), and soil respiration (6.37%) as a result of increased microbial activities in comparison with the 28 g kg-1. [ABSTRACT FROM AUTHOR]

Zinc appeared to be an important modulator with specific functions in plant physiology and increase resistance against different abiotic stresses. Many advances regarding role of zinc under abiotic stress in plants have been made since its revelation, therefore, present study was intended to understand the ameliorating role of zinc on morpho-physiological and biochemical responses of the okra varieties (Anmol and Haseena) when exposed to salt stress. A solution culture experiment was conducted to understand the protective role of zinc in relation to growth, physiological, ionic and antioxidant attributes in two okra varieties under saline condition. The growth medium was salinized with three salinity (Control, 80 mM L−1 and 160 mM L−1 NaCl) and one zinc level (30 µM L−1) applied exogenously in combine and sole form. Salt stress significantly reduces plant dry matter accumulation, chlorophyll contents, relative water contents (RWC), membrane stability index (MSI), K+/Na+ ratio and activities of antioxidant enzymes (POD, SOD, APX, CAT) and these effects are more prominent at high salt level (160 mM). Addition of zinc-alleviated salt toxicity is more conspicuous in okra variety Anmol as compared to variety Haseena as demonstrated by increasing RWC, MSI, K/Na ratio and activities of antioxidant enzymes. Our results suggested that zinc induced salt tolerance in Okra which can serve as a potential source to get sustainable production from salt-affected lands. [ABSTRACT FROM AUTHOR]

Water deficit reduces crop productivity. Cytokinin (CK) is a growth regulator which is a potent coordinator between physiological traits and senescence. A study was carried out to investigate the drought ameliorating effects of exogenous applied cytokinin in wheat. Experiment was comprised of seven treatments(C= Control, DT= Drought at tillering, DT+CK= Drought at tillering + CK, DA= Drought at anthesis, DA+CK= Drought at anthesis + CK, DG= Drought at grain filling, DG+CK= Drought at grain filling + CK).Cytokinin was applied foliarly@ 25 mg L-1 solution of cytokinins. CK application under drought stress significantly increased growth and yield characteristics (P< 0.05). An increase of 4.36%, 7.21% and 5.55% in grain yield was recorded with CK application when drought was applied at tillering, anthesis and grain filling stage, respectively. Other physiological parameters increased by CK included photosynthesis rate, leaf area index, chlorophyll content, activities of ascorbate peroxidase, catalase, peroxidase, superoxide dismutase and endogenous hormonal level of kernels. It was concluded that CK improved plant growth, minimized ill impacts of reactive oxygen species and increase transfer of assimilates to grains under drought. [ABSTRACT FROM AUTHOR]

Drought is a major constraint for agricultural productivity worldwide, and it is likely to further increase. Different strategies are required to mitigate drought stress in plants. In a two-year study that conducted at agronomic research area of the Islamia University of Bahawalpur, we investigated the role of rhizobacteria (RB) and cytokinins (Ck) on drought tolerance, nutrient uptake, yield, and physiological parameters in wheat under drought stress at different developmental stages (tillering, anthesis, and grain filling). Thirteen treatments used were well-watered control plants without RB or Ck, drought at tillering, anthesis, or grain filling without or with RB alone, Ck alone, or combination of both (RB+Ck). In both years, and at the different stages, measured parameters were highest in the well-watered plants but lowest in drought-stressed plants. Application of RB and Ck to drought-stressed plants increased these parameters in the order RB+Ck > RB > Ck. In some cases, under drought stress, there was no difference between inoculation with RB and application of Ck. It was concluded that the combined application of RB and Ck could play a significant role in improving wheat yield and also alleviation of stress under drought condition. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria (PGPR) play an important role in improving crop growth but have not been studied sufficiently. A wire house experiment was conducted in Pakistan to determine the combined effect of inoculating wheat seeds with PGPR on the subsequent growth and yield of the wheat. The experiment included four treatments: T0 – no-inoculation (control), T1 – Azospirillum brasilense inoculation, T2 – Rhizobium pisi inoculation and T3 – co-inoculation with A. brasilense and R. pisi. Development and growth attributes, as well as final yield of wheat, were studied. Co-inoculation of seeds with both strains increased significantly wheat grain yield, the number of grains per plant and 1000-grain weight by 36%, 11% and 17%, respectively, compared to non-inoculated control. While crop growth rate increased for, respectively, 5.5% and 33% at tillering and flag leaf stages, corresponding values for T3 were about 9% and 14% higher than values for sole inoculations in T1 and T2. Co-inoculation also significantly increased leaf epicuticular wax and relative water content as compared to the control treatment. Thus, inoculation of wheat seeds with A. brasilense and R. pisi and their combination is a promising method to improve growth, yield and quality of wheat. [ABSTRACT FROM AUTHOR]