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Introduction: Heat stress caused by global warming adversely affects wheat yield through declining most nutritional quality attributes in grains, excluding grain protein content. Methods: This research investigated the biochemical, physiological, and antioxidant responses of wheat plants under heat stress, focusing on the role of plant growth-promoting bacteria (Micromonospora sp.). Two wheat genotypes were studied: one heat-sensitive and one heat-tolerant, examining their responses to heat stress with and without bacterial inoculation. Results: Under heat stress, the sensitive cultivar experienced significant reductions in photosynthesis rate, chlorophyll content, and RuBisCO activity (57-61%), while the tolerant cultivar had milder reductions (24-28%). Micromonospora sp. treatment notably improved these parameters in the sensitive cultivar (+48-78%), resulting in a substantial increase in biomass production (+43-53%), which was not seen in the tolerant cultivar. Additionally, oxidative stress markers (H2O2 and MDA) were elevated more in the sensitive cultivar (82% and 90% higher) compared to the tolerant one. Micromonospora sp. treatment effectively reduced these markers in the sensitive cultivar (-28% and -27%). Enhanced activity of antioxidant enzymes and ASC-GSH pathway enzymes was particularly evident in Micromonospora sp.-treated sensitive plants. Carbohydrate metabolism shifted, with increased soluble sugars and significant rises in sucrose content in Micromonospora sp.-treated plants under stress. Discussion: The higher soluble sugar levels facilitated amino acid synthesis, contributing to biosynthesis of secondary metabolites, including flavonoids, polyphenols, and anthocyanins. This was reflected in increased activity of phenylalanine ammonia-lyase, cinnamate (CA) 4-hydroxylase, and chalcone synthase enzymes, indicating the activation of phenylpropanoid pathways. Overall, the findings suggest that Micromonospora sp. can mitigate heat stress effects by enhancing photosynthetic efficiency, antioxidant defense, and metabolic adaptations in heat-sensitive wheat cultivars. [ABSTRACT FROM AUTHOR]

Introduction: Salinity negatively affects maize productivity. However, calcium lignosulfonate (CLS) could improve soil properties and maize productivity. Methods: In this study, we evaluated the effects of CLS application on soil chemical properties, plant physiology and grain quality of maize under salinity stress. Thus, this experiment was conducted using three CLS application rates, CLS0, CLS5, and CLS10, corresponding to 0%, 5%, and 10% of soil mass, for three irrigation water salinity (WS) levels WS0.5, WS2.5, and WS5.5 corresponding to 0.5 and 2.5 and 5.5 dS/m, respectively. Results and discussion: Results show that the WS0.5 × CLS10 combination increased potassium (K 0.167 g/kg), and calcium (Ca, 0.39 g/kg) values while reducing the sodium (Na, 0.23 g/kg) content in soil. However, the treatment WS5.5 × CLS0 decreased K (0.120 g/kg), and Ca (0.15 g/kg) values while increasing Na (0.75 g/kg) content in soil. The root activity was larger in WS0.5 × CLS10 than in WS5.5 × CLS0, as the former combination enlarged K and Ca contents in the root while the latter decreased their values. The leaf glutamine synthetase (953.9 µmol/(g.h)) and nitrate reductase (40.39 µg/(g.h)) were higher in WS0.5 × CLS10 than in WS5.5 × CLS0 at 573.4 µmol/(g.h) and 20.76 µg/(g.h), leading to the improvement in cell progression cycle, as revealed by lower malonaldehyde level (6.57 µmol/g). The K and Ca contents in the leaf (881, 278 mg/plant), stem (1314, 731 mg/plant), and grains (1330, 1117 mg/plant) were greater in WS0.5 × CLS10 than in WS5.5 × CLS0 at (146, 21 mg/plant), (201, 159 mg/plant) and (206, 157 mg/plant), respectively. Therefore, the maize was more resistance to salt stress under the CLS10 level, as a 7.34% decline in yield was noticed when salinity surpassed the threshold value (5.96 dS/m). The protein (13.6 %) and starch (89.2 %) contents were greater in WS0.5 × CLS10 than in WS5.5 × CLS0 (6.1 %) and (67.0 %), respectively. This study reveals that CLS addition can alleviate the adverse impacts of salinity on soil quality and maize productivity. Thus, CLS application could be used as an effective soil amendment when irrigating with saline water for sustainable maize production. [ABSTRACT FROM AUTHOR]

Recent anthropogenic sources and excess usage have immensely threatened the communities and habitat ecology of this region's medicinally and economically significant crops. Therefore, our study aims to evaluate the community structure and related environmental characteristics sustaining Nasturtium officinale communities along the river basin (RB) in Northwest Pakistan, using the clustering procedure (Ward's method) and Redundancy analysis (RDA). From 340 phytosociological plots (34 x 10 = 340), we identified four ecologically distinct assemblages of N. officinale governed by different environmental and anthropogenic factors for the first time. The floristic structure shows the dominance of herbaceous (100%), native (77%), and annual (58.09%) species indicating relatively stable communities; however, the existence of the invasive plants (14%) is perturbing and may cause instability in the future, resulting in the replacement of herbaceous plant species. Likewise, we noticed apparent variations in the environmental factors, i.e., clay percentage (p = 3.1 x 10-5), silt and sand percentage (p< 0.05), organic matter (p< 0.001), phosphorus and potassium (p< 0.05), and heavy metals, i.e., Pb, Zn, and Cd (p< 0.05), indicating their dynamic role in maintaining the structure and composition of these ecologically distinct communities. RDA has also demonstrated the fundamental role of these factors in species-environment correlations and explained the geospatial variability and plants' ecological amplitudes in the Swat River wetland ecosystem. We concluded from this study that N. officinale communities are relatively stable due to their rapid colonization; however, most recent high anthropogenic interventions especially overharvesting and sand mining activities, apart from natural enemies, water deficit, mega-droughts, and recent flood intensification due to climate change scenario, are robust future threats to these communities. Our research highlights the dire need for the sustainable uses and conservation of these critical communities for aesthetics, as food for aquatic macrobiota and humans, enhancing water quality, breeding habitat, fodder crop, and its most promising medicinal properties in the region. [ABSTRACT FROM AUTHOR]

Introduction: Heat stress caused by global warming adversely affects wheat yield through declining most nutritional quality attributes in grains, excluding grain protein content., Methods: This research investigated the biochemical, physiological, and antioxidant responses of wheat plants under heat stress, focusing on the role of plant growth-promoting bacteria ( Micromonospora sp.). Two wheat genotypes were studied: one heat-sensitive and one heat-tolerant, examining their responses to heat stress with and without bacterial inoculation., Results: Under heat stress, the sensitive cultivar experienced significant reductions in photosynthesis rate, chlorophyll content, and RuBisCO activity (57-61%), while the tolerant cultivar had milder reductions (24-28%). Micromonospora sp. treatment notably improved these parameters in the sensitive cultivar (+48-78%), resulting in a substantial increase in biomass production (+43-53%), which was not seen in the tolerant cultivar. Additionally, oxidative stress markers (H 2 O 2 and MDA) were elevated more in the sensitive cultivar (82% and 90% higher) compared to the tolerant one. Micromonospora sp. treatment effectively reduced these markers in the sensitive cultivar (-28% and -27%). Enhanced activity of antioxidant enzymes and ASC-GSH pathway enzymes was particularly evident in Micromonospora sp.-treated sensitive plants. Carbohydrate metabolism shifted, with increased soluble sugars and significant rises in sucrose content in Micromonospora sp.-treated plants under stress., Discussion: The higher soluble sugar levels facilitated amino acid synthesis, contributing to biosynthesis of secondary metabolites, including flavonoids, polyphenols, and anthocyanins. This was reflected in increased activity of phenylalanine ammonia-lyase, cinnamate (CA) 4-hydroxylase, and chalcone synthase enzymes, indicating the activation of phenylpropanoid pathways. Overall, the findings suggest that Micromonospora sp. can mitigate heat stress effects by enhancing photosynthetic efficiency, antioxidant defense, and metabolic adaptations in heat-sensitive wheat cultivars., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hassan, Ahmed, Sheteiwy, Alhaj Hamoud, Okla, AlGarawi, Maridueña-Zavala, Alaraidh, Reyad and Abdelgawad.)

Introduction: Salinity negatively affects maize productivity. However, calcium lignosulfonate (CLS) could improve soil properties and maize productivity., Methods: In this study, we evaluated the effects of CLS application on soil chemical properties, plant physiology and grain quality of maize under salinity stress. Thus, this experiment was conducted using three CLS application rates, CLS 0 , CLS 5 , and CLS 10 , corresponding to 0%, 5%, and 10% of soil mass, for three irrigation water salinity (WS) levels WS 0.5 , WS 2.5 , and WS 5.5 corresponding to 0.5 and 2.5 and 5.5 dS/m, respectively., Results and Discussion: Results show that the WS 0.5 × CLS 10 combination increased potassium (K 0.167 g/kg), and calcium (Ca, 0.39 g/kg) values while reducing the sodium (Na, 0.23 g/kg) content in soil. However, the treatment WS 5.5 × CLS 0 decreased K (0.120 g/kg), and Ca (0.15 g/kg) values while increasing Na (0.75 g/kg) content in soil. The root activity was larger in WS 0.5 × CLS 10 than in WS 5.5 × CLS 0 , as the former combination enlarged K and Ca contents in the root while the latter decreased their values. The leaf glutamine synthetase (953.9 µmol/(g.h)) and nitrate reductase (40.39 µg/(g.h)) were higher in WS 0.5 × CLS 10 than in WS 5.5 × CLS 0 at 573.4 µmol/(g.h) and 20.76 µg/(g.h), leading to the improvement in cell progression cycle, as revealed by lower malonaldehyde level (6.57 µmol/g). The K and Ca contents in the leaf (881, 278 mg/plant), stem (1314, 731 mg/plant), and grains (1330, 1117 mg/plant) were greater in WS 0.5 × CLS 10 than in WS 5.5 × CLS 0 at (146, 21 mg/plant), (201, 159 mg/plant) and (206, 157 mg/plant), respectively. Therefore, the maize was more resistance to salt stress under the CLS 10 level, as a 7.34% decline in yield was noticed when salinity surpassed the threshold value (5.96 dS/m). The protein (13.6 %) and starch (89.2 %) contents were greater in WS 0.5 × CLS 10 than in WS 5.5 × CLS 0 (6.1 %) and (67.0 %), respectively. This study reveals that CLS addition can alleviate the adverse impacts of salinity on soil quality and maize productivity. Thus, CLS application could be used as an effective soil amendment when irrigating with saline water for sustainable maize production., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Alhaj Hamoud, Shaghaleh, Zhang, Okla, Alaraidh, AbdElgawad and Sheteiwy.)