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Background: Blackgrm is one of the most important pulse crops majorly cultivated in rainfed conditions of India. Soil moisture deficit, low and erratic rainfall, use of poor quality seeds, poor crop stand and improper crop management resulting in lower productivity in rainfed ecosystem. Reduced crop stand alone leads to 30% deficit in production. Availability of technology to overcome drought stress is one of the way to expand blackgram cultivation in dry tracks. Hydrophilic polymers may have great potential in restoration and reclamation, when used the polymers correctly and an ideal situations will have atleast 95% of their stores water available for plant absorption. There are N number of inorganic polymers available in the market, that can be applied in the form of soil application. Studies on Hydrophilic bio polymer seed coating to mitigate water stress is very megar or nil. Hence, the present study was formulated in blackgram as hydrophilic bio polymer seed coating on seed germination and field emergence. Methods: Seed coating experiment consists of seven hydrophilic biopolymers (Ethyl cellulose, Methyl cellulose, Carboxyl methyl cellulose, Agar, Gum Arabic, Xanthangum and Carrageenan); two coating methods (dry and dry powder concoction). The germination test conducted in sand media with 60% Water Holding Capacity of sand and PEG induced water stress and evaluated for seed quality parameters against uncoated seeds. Field experiments conducted with water stress periods of 10 days, 20 days and 25 days after life irrigation and observed for biometric and yield parameters. Result: Results revealed that blackgram seeds coated with bio polymerconcoctionof xanthan gum : carrageenan : Agar agar (4:1:1) @ 20 g/kg performed better in terms ofall seed quality parameters and withstand water stress upto 20 days after life irrigation with the yield increase of 53% over stressed control (Skipping irrigation for 20 days after life irrigation) and can be recommended as a pre sowing treatment for drought mitigation in blackgram. [ABSTRACT FROM AUTHOR]

This work investigated the effects of moisture absorption treatment on composite−to−metal double−lap shear joints (DLSJs) bonded with epoxy adhesive film through experiments and simulations. The composite−to−metal DLSJ can be divided into five parts (the interface between the composite and adhesive, the interface between the adhesive and metal, the composite adherend, the metal adherend, and the adhesive layer). First, the wet−dependent properties of the adhesive and interfaces were obtained through adhesive tensile tests and GC tests, which showed that the properties of the adhesive and interfaces were significantly affected by the moist environment. Then, tensile tests of the composite−to−metal double−lap shear joints were carried out in dry and wet environments. Finally, based on the experimental investigations, a finite element (FE) model that considered cohesive damage was established for simulating damage evolution and predicting the failure loads and failure modes of the DLSJs. The results of both the experimental and numerical tests show that the DLSJ failure load decreases significantly after immersion in 95 °C water, and the major failure mode transfers from adhesive failure to interface failure. The research results provide a theoretical basis or basic data for the structural design of adhesively bonded composite−to−metal. [ABSTRACT FROM AUTHOR]

In the eastern Indo‐Gangetic plains, chickpea is grown postrice cultivation mostly under rainfed condition with residual soil moisture which adversely affects branching as well as pod and seed development, ultimately resulting in substantial yield losses. The current study analysed the moisture stress response of 12 chickpea genotypes with control for different morpho‐physiological traits in two sets of field experiments carried out during the year 2017–18 and 2018–19. The current study observed varying response of chickpea genotypes under moisture stress condition with average yield reduction from 11.79% to 24.77%. Mean yield of genotypes under stress condition showed a strong positive association with yield index (1.00**) and stress tolerance index (0.915**). The biplot principal component analysis revealed maximum potential of three chickpea genotypes (DBGC 1, Pusa 256 and DBGC 2) for grain yield and biological yield under moisture stress condition. The correlation analysis showed a significant association of yield with physiological parameters such as photosynthetic rate (0.363**), stomatal conductance (0.364**) and transpiration rate (0.292*). The three higher yielding genotypes relatively maintained biological yield, yield plant−1, 100 seed weight and photosynthesis rate and showed reduced rates of stomatal conductance and transpiration under moisture stress condition. The study found variable genotypic response to moisture stress and showed that yield index as well as stress tolerance index was more effective to identify superior genotypes for moisture stress condition. The superior genotypes identified in the present study may be considered for rainfed areas of eastern Indo‐Gangetic plains and can be used in future chickpea breeding programs for drought tolerance. [ABSTRACT FROM AUTHOR]

Identification of tolerant mulberry genotypes and elucidation of stress-tolerant mechanisms are two priority areas need to be addressed for sustainable mulberry leaf production. In the present study, 16 mulberry genotypes were evaluated under at low (75% FC), medium (50% FC), and high moisture stress (25% FC) conditions along with well-irrigated plants (100% FC) and measured the photosynthetic efficiency and antioxidant potential. In well-irrigated plants, photosynthetic rate was high in S13 (16.45 µmol/m2/s), Mysore Local, RC2, and AGB8 (13.62–16 µmol/m2/s). All genotypes showed a gradual decline in photosynthetic rate during the progression of moisture stress (low to high stress). MSG2, AGB8, RC1, RC2, and Nagalur Estate showed high photosynthetic rate (7.45–10.15 µmol/m2/s) under high moisture stress, whereas low photosynthetic rate was recorded in Mysore Local (3.46 µmol/m2/s) and K2 (3.50 µmol/m2/s). All tolerant genotypes showed higher activities of SOD (104.25–122.44 Units/g) and POX (25.61–33.73 Units/g) activities under high moisture stress. Bundi-3, S34, RC2, and AGB8 showed higher SOD activity and low enzyme activity was observed in K2. Non-enzymatic antioxidants and osmolytes were high in moisture stress-tolerant genotypes. This study identified that high photosynthetic rate is one of the important physiological indicator for moisture stress tolerance in mulberry. Also higher activities of antioxidant enzymes (SOD and POX), presence of high quantity of non-enzymatic antioxidants (ascorbic acids, reduced glutathione, and phenols), and accumulation of osmolytes (proline and glycine betaine) are identified as stress tolerance biochemical markers in mulberry genotypes. Evaluation Index (EI) value was calculated and genotypes suitable for well-irrigated condition as well as for low, medium, and high moisture stress conditions were identified based on EI values. [ABSTRACT FROM AUTHOR]

Drought is one of the most important abiotic stresses limiting the survival, growth, and productivity of plants in many regions of the world. This study was conducted to evaluate drought tolerance of the recombinant genotypes of two species of orchardgrass and smooth bromegrass based on clonal evaluation and stress tolerance indices. In this study, 36 genotypes selected from polycross populations of both species of orchardgrass and smooth bromegrass were evaluated in terms of phenological, agronomic and morphological traits under normal (50% water depletion from the root zone depth) and drought-stressed (90% water depletion from the root zone depth) conditions during 2013 to 2015 at the Research Farm of Isfahan University of Technology, Isfahan, Iran. To evaluate drought tolerance of the mentioned genotypes, five drought tolerance and susceptibility indices including stress tolerance indices (TOL and STI), mean productivity index (MP), geometric mean productivity (GMP) and stress sensitivity index (SSI) were calculated based on forage yield under drought stress (Ys) and non- stress (Yp) conditions. In both species, high genetic variation was observed among genotypes in terms of most of the studied traits and indices. In orchardgrass, the genetic coefficient of variation varied from 4.31% to 23.5% under normal condition, and from 1.31% to 21.3% under drought stress condition. In smooth bromegrass, the range of genetic coefficient of variation was variable from 2.05-21.4% under normal condition and 1.66-24.6% under drought stress condition. This indicated a high potential for improving these traits through targeted selection in breeding programs of the two species. Drought stress significantly affected most of the studied traits and reduced the genetic variability of traits except for days to ear emergence, days to pollination, percentage of dry matter yield of cut 1, and percentage of dry matter yield of cut 2 in orchardgrass, and percentage of dry matter yield of cut 1 and percentage of dry matter yield of cut 3 in smooth bromegrass. The amount of this reduction for dry matter yield of cuts 1, 2 and 3 was 47.5, 67.3, and 66.6 percent, respectively, in orchardgrass, and 37.4, 49.5, and 49.4 percent, respectively, in smooth bromegrass. Low heritability for forage yield (24.7, 13.5, and 25.9 percent for dry matter yield of cut 1, dry matter yield of cut 2, and dry matter yield of cut 3, respectively, in orchardgrass, and 59.5, 45.9, and 59.4 percent for dry matter yield of cut 1, dry matter yield of cut 2, and dry matter yield of cut 3, respectively, in smooth bromegrass) suggested that direct selection based on forage yield is not effective for the improvement of this trait. Though, indirect selection based on components of forage yield which have high heritability and high correlation with yield (i.e. plant height, stems/plant, and crown diameter in both species), would be more effective. In both species, selection indices of MP, GMP, and STI had a positive and significant correlation with forage yield (0.92, 0.75, and 0.75, respectively, under normal condition, and 0.61, 0.81, and 0.77, respectively, under drought-stressed condition, in orchardgrass; and 0.95, 0.92, and 0.88, respectively, under normal condition, and 0.91, 0.95, and 0.95, respectivel, under drought-stressed condition, in smooth bromegrass). Therefore, these indices were identified as desirable ones in the selection of drought tolerant cultivars in orchardgrass and smooth bromegrass. Based on the results of principal component analysis and drought tolerance and susceptibility indices, the genotypes of 13 and 14 in orchardgrass, and 13 and 32 in smooth bromegrass were identified as superior genotypes in terms of forage yield and drought tolerance. These genotypes can be used as superior parents for the development of genetic populations to improve forage yield and stress tolerance and create synthetic cultivars.

Worldwide, it has been recorded extensively that plants are subjected to severe abiotic and biotic stressors. The scientific research community has widely reported that multi-abiotic stressors cause horticultural crop losses, accounting for at least 50 to 70% of the crop yield and quality losses. Therefore, this review focused on the detrimental effects caused by abiotic stress factors occurring in single-, combined- and multi-cell stresses on horticultural plants worldwide, along with the best production systems practices for mitigation during and post-single and combined abiotic or multi-stress damages. A conclusion and recommendation could be reached using the pool of research material, which constituted research articles, reviews, book chapters, thesis, research short communications and industrial short communications from at least twenty-five years ago. Findings showed that some of the leading abiotic stresses are single- and combined abiotic stressors like water deficit, salinity, soil pH, phosphate deficiency, wounding, soil density and pot size. Established commercial and smallholder farmers are globally adapting to plant growth regulators and biostimulants as part of their production systems. However, as much as the effectiveness of biostimulants containing humic acids, algal extracts, plant growth-promoting microorganisms and phytohormones has been reported to promote plant development under multi-stress, only a few studies are focusing on organic phytohormone-based biostimulants on horticultural crops grown under adverse multi stress factoring. In conclusion, the review recommends alternative solutions for emerging South African farmers and growers who cannot afford agricultural insurance options and energy alternatives on the common single- and combined abiotic- or multi-stress-factors.

Moisture stress poses a significant threat to global agriculture, compromising crop yields and food security. In the quest for sustainable solutions, endophytic microorganisms have emerged as promising candidates for enhancing plant resilience to drought. The study's primary goal was to analyse the significance of bacterial endophytes, both rhizobial and passenger endophytes, in alleviating the effects of moisture stress. Here, PEG 6000 was used to test the drought endurance of the ten identified rhizobial and passenger endophytes. Rhizobium pusense S6R2, Enterobacter cloacae S23 and Bacillus tequilensis NBB13 were selected as best performing endophytes as they showed high tolerance of poly ethylene glycol (PEG) and maximum plant growth promoting traits like Indole Acetic Acid, exopolysaccharide production, biofilm formation, 1-aminocyclopropane1-carboxylate (ACC) deaminase activity, siderophore, zinc and phosphorous solubilisation even in PEG induced moisture stress condition. Metabolite analysis revealed that twenty-four significant compounds mostly belong to fatty acyls, amino acids, peptides, polyketides, and benzenoids were found in the root exudates of groundnut treated with endophytes. The best-performing endophytes were used in a pot culture experiment, with groundnut as the test crop. The current study found that co-inoculation of Rhizobium pusense S6R2 and Enterobacter cloacae S23 significantly increased nodule number, growth, photosynthetic pigment, anti-oxidant enzymes, and osmolyte under moisture stressed conditions when compared to other treatments. As a result, co-inoculation of Rhizobium and entophytic bacteria may be recommended as a bio-inoculant for groundnut for moisture stress alleviation after confirming the results in field evaluation.

The promotion of climate-resilient practices (CRPs) requires the development of the capacity of farmers to adopt these practices owing to the knowledge-intensive nature of technologies. Extension services serve as a conduit for facilitating the conceptualization of CRPs and are instrumental in improving the resiliency and mitigation of climate change. We used a social-ecological framework and a multivariate probit model to analyze the drivers of the CRP uptake in moisture-stressed areas in Ethiopia, with a particular focus on extension services. Unlike previous studies that investigated a single technology, we considered a bundle of technologies. We focused on the use of two capital-intensive CRPs (drought-resistant seed and inorganic fertilizer) and four knowledge-intensive CRPs (minimum tillage, farmyard manure, water-saving technology, and crop residue retention). The role of extension services in promoting other CRPs beyond input and capital-intensive technologies was insignificant. Heterogeneity analysis revealed that the correlation between extension services and the adoption of other knowledge-intensive natural resource management practices holds irrespective of the proximity to the extension service providers. This finding highlights the need for targeted and tailored interventions that support farmers to address the challenges faced by them in moisture-stressed areas. Accordingly, we propose continuously improving the ability of the extension service providers to promote climate-change adaptation knowledge and practices. This should be accompanied by efforts to strengthen a pluralistic extension system, improve land tenure security, and decrease transaction costs for farmers through output market linkages.

The increased depletion of ground water resources poses the risk of higher moisture stress environment for agriculture crops. The rapid increase in the moisture stress situation imposes the need of efficient agricultural research on determining the impact of moisture stress on variety of crops. The prime objective of the proposed work is building an IoT based Plant Phenotyping Device for moisture stress experimental study on variety of crops with deep learning model for stress response detection. In this work, IoT technology is used for building a proposed system for conducting the moisture stress experiments on plants and adopting the image processing and convolution neural network based model for stress prediction. The accuracy of the proposed system was experimentally evaluated and empirical results were satisfactory in maintaining the desired level of moisture stress. Performance analysis of LeNet, AlexNet, customized AlexNet and GoogLeNet CNN models were carried out with hyper-parameters variations on the leaf images. GoogLeNet achieved a better validation accuracy of 96% among other models. The trained GoogLeNet model is used for predicting the moisture stress response and predicted results were matched with manual observation of stress response. The affirmative results of proposed system would increases its adoption for in-house precision agriculture and also for conducting various moisture stress experiments on variety of crops. The confirmative detection of moisture stress tolerance level of plant provides knowledge on minimum level of water requirement for plant growth, which in-turn save the water by avoiding excess watering to plants. [ABSTRACT FROM AUTHOR]

Background: Temperate forests of eastern North America will be increasingly affected by chronic atmospheric nitrogen deposition, elevated temperatures, and drought events that will expose trees to moisture‐stressed conditions in non‐nitrogen‐limited soils. Yet, little is known regarding the response of sugar maple‐dominated forests to moisture stress under non‐nitrogen‐limiting conditions. Aims: The objective of this greenhouse study was to analyze the effects of moisture stress on the nutrition and growth of sugar maple seedlings growing on base‐poor forest soils that were strongly fertilized with nitrogen. Methods: One‐year‐old sugar maple seedlings were grown with and without water stress on soils from a sugar maple stand that had been fertilized for 15 years at a rate of 85 kg N ha−1 y−1. Results: Decreased moisture availability decreased total, leaf, root and stem biomass, and root/stem ratio. Leaf concentrations of N, P, Ca, and Mg and root concentrations of K, Ca, and Mg were 6% to 23% significantly lower under stressed versus unstressed conditions despite no changes in N, P, K, and Mg concentrations in the soil. Only soil Ca concentration was negatively affected by the moisture stress treatment. Soil and leaf δ15N and the k‐factor (i.e., isotopic discrimination effect of 15N‐labeled sources of N between roots and soil) that was used to assess N‐use efficiency of sugar maple seedlings did not differ between water stress treatments. Conclusions: Our results indicate that decreasing root biomass of sugar maple seedlings under moisture stress in non‐nitrogen‐limiting situations would decrease their ability to take up nutrients that are necessary for growth and induce lower concentrations in leaves and roots. Expected severe drought events could substantially limit nutrient uptake capacity of sugar maple seedlings on sites that are subject to chronic atmospheric N‐deposition, which would contribute to dieback in sugar maple stands. [ABSTRACT FROM AUTHOR]

Drought is one of the most important abiotic stresses limiting the survival, growth, and productivity of plants in many regions of the world. This study was conducted to evaluate drought tolerance of the recombinant genotypes of two species of orchardgrass and smooth bromegrass based on clonal evaluation and stress tolerance indices. In this study, 36 genotypes selected from polycross populations of both species of orchardgrass and smooth bromegrass were evaluated in terms of phenological, agronomic and morphological traits under normal (50% water depletion from the root zone depth) and drought-stressed (90% water depletion from the root zone depth) conditions during 2013 to 2015 at the Research Farm of Isfahan University of Technology, Isfahan, Iran. To evaluate drought tolerance of the mentioned genotypes, five drought tolerance and susceptibility indices including stress tolerance indices (TOL and STI), mean productivity index (MP), geometric mean productivity (GMP) and stress sensitivity index (SSI) were calculated based on forage yield under drought stress (Ys) and non- stress (Yp) conditions. In both species, high genetic variation was observed among genotypes in terms of most of the studied traits and indices. In orchardgrass, the genetic coefficient of variation varied from 4.31% to 23.5% under normal condition, and from 1.31% to 21.3% under drought stress condition. In smooth bromegrass, the range of genetic coefficient of variation was variable from 2.05-21.4% under normal condition and 1.66-24.6% under drought stress condition. This indicated a high potential for improving these traits through targeted selection in breeding programs of the two species. Drought stress significantly affected most of the studied traits and reduced the genetic variability of traits except for days to ear emergence, days to pollination, percentage of dry matter yield of cut 1, and percentage of dry matter yield of cut 2 in orchardgrass, and percentage of dry matter yield of cut 1 and percentage of dry matter yield of cut 3 in smooth bromegrass. The amount of this reduction for dry matter yield of cuts 1, 2 and 3 was 47.5, 67.3, and 66.6 percent, respectively, in orchardgrass, and 37.4, 49.5, and 49.4 percent, respectively, in smooth bromegrass. Low heritability for forage yield (24.7, 13.5, and 25.9 percent for dry matter yield of cut 1, dry matter yield of cut 2, and dry matter yield of cut 3, respectively, in orchardgrass, and 59.5, 45.9, and 59.4 percent for dry matter yield of cut 1, dry matter yield of cut 2, and dry matter yield of cut 3, respectively, in smooth bromegrass) suggested that direct selection based on forage yield is not effective for the improvement of this trait. Though, indirect selection based on components of forage yield which have high heritability and high correlation with yield (i.e. plant height, stems/plant, and crown diameter in both species), would be more effective. In both species, selection indices of MP, GMP, and STI had a positive and significant correlation with forage yield (0.92, 0.75, and 0.75, respectively, under normal condition, and 0.61, 0.81, and 0.77, respectively, under drought-stressed condition, in orchardgrass; and 0.95, 0.92, and 0.88, respectively, under normal condition, and 0.91, 0.95, and 0.95, respectivel, under drought-stressed condition, in smooth bromegrass). Therefore, these indices were identified as desirable ones in the selection of drought tolerant cultivars in orchardgrass and smooth bromegrass. Based on the results of principal component analysis and drought tolerance and susceptibility indices, the genotypes of 13 and 14 in orchardgrass, and 13 and 32 in smooth bromegrass were identified as superior genotypes in terms of forage yield and drought tolerance. These genotypes can be used as superior parents for the development of genetic populations to improve forage yield and stress tolerance and create synthetic cultivars. [ABSTRACT FROM AUTHOR]

Simple Summary: Seed-based restoration is likely to become less successful with climate change due to reduced seed germination and seedling emergence. Studying how native plant species respond to environmental stress using a whole life cycle approach can help predict climate change impacts on successful plant establishment. Therefore, the aim of this study was to understand how temperature and moisture stress affect seed germination and seedling emergence together with determining how soil moisture stress can impact the reproductive biology of plants. A native Australian legume species, Desmodium brachypodum A. Gray, was selected as a model species. The seed germination and seeding emergence were reduced by more than half when exposed to elevated temperatures and moisture stress. When the plants produced seeds under moisture stress, the duration of seed production and the number of produced seeds decreased. On the other hand, no differences were observed in the seed traits of those produced seeds. In conclusion, the reproductive output of D. brachypodum had low seed variability under moisture stress, which might be useful when sourcing seeds from climates with high variability. Even so, a reduction in the seed quantity under maternal moisture stress can impact the long-term survival of restored plant populations. Understanding how seed functional traits interact with environmental factors to determine seedling recruitment is critical to assess the impact of climate change on ecosystem restoration. This study focused on the effects of environmental factors on the mother plant during early plant life history stages and during seed development. Desmodium brachypodum A. Gray (large tick trefoil, Fabaceae) was used as a model species. Firstly, this study analyzed seed germination traits in response to temperature and moisture stress. Secondly, it investigated how seed burial depth interacts with temperature and soil moisture to influence seedling emergence traits. Finally, it determined if contrasting levels of post-anthesis soil moisture could result in changes in D. brachypodum reproductive biology and seed and seedling functional traits. The results showed that elevated temperature and moisture stress interacted to significantly reduce the seed germination and seedling emergence (each by >50%), while the seed burial improved the seedling emergence. Post-anthesis soil moisture stress negatively impacted the plant traits, reducing the duration of the reproductive phenology stage (by 9 days) and seed production (by almost 50%). Unexpectedly, soil moisture stress did not affect most seed or seedling traits. In conclusion, elevated temperatures combined with low soil moisture caused significant declines in seed germination and seedling emergence. On the other hand, the reproductive output of D. brachypodum had low seed variability under soil moisture stress, which might be useful when sourcing seeds from climates with high variability. Even so, a reduction in seed quantity under maternal moisture stress can impact the long-term survival of restored plant populations. [ABSTRACT FROM AUTHOR]

Introduction: Drought is one of the most important abiotic stresses that affects plant growth, development and biochemical processes of plants such as the production of secondary metabolites and aromatic chemical compounds. Salvia subgenus Perovskia belongs to the Lamiaceae family and it has numerous therapeutic properties. In general, the anti-oxidative defense mechanisms are mainly classified into enzymatic (e.g., guaiacol peroxidase, and ascorbate peroxidase) and non-enzymatic, i.e., polyphenolic compounds, terpenoids, proline, which can coordinately detoxify excess reactive oxygen species in the cells. Indeed, water deficit stress can impose profound effects on quality and quantity of essential oils in aromatic plants. Materials and Methods: In order to investigate the effects of limited irrigation on polyphenol contents, antioxidant enzyme activities and essential oil constituents of two populations of S. abrotanoides viz., Abyaneh and Mezdeh populations, as endemic species of Iran, a randomized complete block design with three replications was conducted at the Research Farm of Isfahan University of Technology, in two consecutive years 2020-2021. Water deficit levels included field capacity (as control), 70% of field capacity (mild stress), and 50% of field capacity (severe stress). Results and Discussion: The results showed that total phenolic content, total flavonoids, antioxidant enzymes activities, proline content, and essential oil yield substantially increased with the severity of stress as compared with well-watered plants. Furthermore, the highest contents of total phenolics, total flavonoids, and antioxidant activities were obtained in Abyaneh population in comparison to the other ones at the second year of cultivation. In other words, Abyaneh has a greater capacity in regulating water deficit stress than the other population. The essential oil content ranged from 1.01 to 2.82% in Abyaneh population and 0.78 to 2.04% in Mezdeh population. The analysis of the essential oils by GC/MS revealed the presence of a large number of components represented mainly by oxygenated monoterpenes. Camphor concentration ranged from 18.28% (Abyaneh population and mild stress) to 29.26% (Mezdeh population and severe stress). The amount of berneol ranged from 1.18% (Mezdeh population and well-watered level) to 4.34% (Mezdeh population and mild stress), and the level of δ-3-carene ranged from 1.62% (Mezdeh population and severe stress) to 11.81% (Abyaneh population and mild stress). The highest and lowest amount of 1,8-cineole were found in Abyaneh population under mild stress level (25.79%) and Mezdeh population under well-watered level (15.95%), respectively. Among main essential oil compositions, Abyaneh population showed the highest amount of α-pinene under well-watered level (10.81%), while this population had the lowest value (5.04%) under severe stress level. Furthermore, the concentration of myrcene were obtained in the range of 0.59% to 9.90%, in which the highest value was observed for the sample collected from Abyaneh population under severe stress level, while the sample of this population under well-watered along with mild stress levels showed the lowest values. In both plant populations, the proportions of oxygenated monoterpenes were elevated with increasing stress severity while the sesquiterpenes (sesquiterpene hydrocarbons and oxygenated sesquiterpenes) decreased. In addition, the percentage of all prominent volatile constituents including δ-3-carene, camphor, 1,8-cineole, berneol, myrcene and α-pinene elevated at the levels of mild and severe stress, and it suggested that water stress conditions improved the quality of the studied essential oils. Conclusion: Finally, it can be concluded that mild and severe drought stress significantly increased secondary metabolites, antioxidant activities, and the percentage of prominent volatile constituents, which provided an insight for improving the qualitative and quantitative status of bioactive components of S. abrotanoides with moisture-stress management practices. [ABSTRACT FROM AUTHOR]

Premise: The soil microbiome plays a role in plant trait expression and fitness, and plants may be locally adapted or maladapted to their soil microbiota. However, few studies of local adaptation in plants have incorporated a microbial treatment separate from manipulations of the abiotic environment, so our understanding of microbes in plant adaptation is limited. Methods: Here we tested microbial effects on local adaptation in four paired populations of an abundant alpine plant from two community types, dry and moist meadow. In a 5‐month greenhouse experiment, we manipulated source population, soil moisture, and soil microbiome and measured plant survival and biomass to assess treatment effects. Results: Dry meadow populations had higher biomass than moist meadow populations at low moisture, demonstrating evidence of local adaptation to soil moisture in the absence of microbes. In the presence of microbes, dry meadow populations had greater survival than moist meadow populations when grown with dry meadow microbes regardless of moisture. Moist meadow populations showed no signs of adaptation or maladaptation. Conclusions: Our research highlights the importance of microbial mutualists in local adaptation, particularly in dry environments with higher abiotic stress. Plant populations from environments with greater abiotic stress exhibit different patterns of adaptation when grown with soil microbes versus without, while plant populations from less abiotically stressful environments do not. Improving our understanding of the role microbes play in plant adaptation will require further studies incorporating microbial manipulations. [ABSTRACT FROM AUTHOR]

This work investigated the effects of moisture absorption treatment on composite−to−metal double−lap shear joints (DLSJs) bonded with epoxy adhesive film through experiments and simulations. The composite−to−metal DLSJ can be divided into five parts (the interface between the composite and adhesive, the interface between the adhesive and metal, the composite adherend, the metal adherend, and the adhesive layer). First, the wet−dependent properties of the adhesive and interfaces were obtained through adhesive tensile tests and GC tests, which showed that the properties of the adhesive and interfaces were significantly affected by the moist environment. Then, tensile tests of the composite−to−metal double−lap shear joints were carried out in dry and wet environments. Finally, based on the experimental investigations, a finite element (FE) model that considered cohesive damage was established for simulating damage evolution and predicting the failure loads and failure modes of the DLSJs. The results of both the experimental and numerical tests show that the DLSJ failure load decreases significantly after immersion in 95 °C water, and the major failure mode transfers from adhesive failure to interface failure. The research results provide a theoretical basis or basic data for the structural design of adhesively bonded composite−to−metal.

Durum wheat is a staple food in the Mediterranean Basin, mostly cultivated under rainfed conditions. As such, the crop is often exposed to moisture stress. Therefore, the identification of genetic factors controlling the capacity of genotypes to convert moisture into grain yield (i.e. water productivity) is quintessential to stabilize production despite climatic variations. A global panel of 384 accessions was tested across 18 Mediterranean environments (in Morocco, Lebanon, and Jordan) representing a vast range of moisture levels. The accessions were assigned to water responsiveness classes, with genotypes 'Responsive to Low Moisture' reaching an average +1.5 kg ha–1 mm–1 yield advantage. Genome wide association studies revealed that six loci explained most of this variation. A second validation panel tested under moisture stress confirmed that carrying the positive allele at three loci on chromosomes 1B, 2A, and 7B generated an average water productivity gain of +2.2 kg ha–1 mm–1. These three loci were tagged by kompetitive allele specific PCR (KASP) markers, and these were used to screen a third independent validation panel composed of elites tested across moisture stressed sites. The three KASP combined predicted up to 10% of the variation for grain yield at 60% accuracy. These loci are now ready for molecular pyramiding and transfer across cultivars to improve the moisture conversion of durum wheat. [ABSTRACT FROM AUTHOR]

Introduction: Drought stress is known as one of the most important factors limiting the growth and production of agricultural plants in most parts of the world and Iran. It is a multidimensional stress and affects plants at different levels. From a physiological point of view, drought stress causes several changes in the relative water content of leaves and photosynthetic pigments of plants, which in turn causes a decrease in the efficiency of photosynthesis and a significant reduction in plant growth parameters and ultimately grain yield. In Iran, drought stress usually occurs during the filling stage of wheat grains, and due to the limitation of irrigation, supplementary irrigation can play an important role in dealing with drought stress. Durum wheat (Triticum durum, Desf) is an important food product due to its heavy gluten properties and non-sticky dough, ideal for preparing pasta products such as macaroni and spaghetti. Materials and methods: To investigate the physiological characteristics, yield, and yield components of durum wheat cultivars under drought conditions and supplemental irrigation, 10 durum wheat genotypes were evaluated in the form of a split-plot design with the basis of randomized complete blocks in dryland and supplemental irrigation with 3 replications during Crop years 2017-2018 and 2018-2019 in Kohdasht city of Lorestan province. Grain yield and yield components (weight of 1000 seeds, number of seeds per spike, number of spikes per plant) as well as biochemical and physiological properties of photosynthetic pigments, greenness index, relative leaf water, leaf protein and light consumption efficiency were investigated. Results: Variance analysis showed a significant variation among the examined cultivars, moisture conditions, as well as the interaction of cultivar × humidity conditions for most of the traits except the interaction effect of cultivar × humidity conditions for chlorophyll b and leaf protein. The effect of year and interaction effects of year with other factors were not significant for most of the traits. Performing supplementary irrigation compared to rainfed conditions caused all traits to increase significantly, except greenness index and protein content. Mean comparison of interaction effect of cultivar × moisture environment with Duncan's method at 5% level showed that the genotypes reacted differently for the traits in two moisture conditions and in dry conditions, Omrabi3, Hana, Aria and Saji genotypes were superior to other genotypes in terms of agricultural and physiological traits, and with supplementary irrigation, these for genotypes maintained their superiority, and two genotypes, Shabrang and Behrang, were added to this group. Conclusion: In general, it can be said that the results were almost the same in the two years studied. Supplementary irrigation compared to rainfed conditions improved the agronomic and physiological characteristics of the cultivars. Among the genotypes, there was a high diversity for all the examined traits and this diversity was different in two humidity conditions. Considering the two-year mean yield, the genotypes of Omrabi3, Saji, Arya and Hana for rainfed conditions and Omrabi3, Hana and Behrang for supplementary irrigation conditions of the studied area are recommended. [ABSTRACT FROM AUTHOR]

Water deficit is a crucial factor causing huge loss to rice productivity. The present study aimed to develop a multiple stress tolerant genotype by pyramiding drought tolerant yield QTLs qDTY1.1 and qDTY3.1 into high yielding rice variety Samba Mahsuri Sub-1(SMS) through marker assisted pyramiding. To achieve this six introgression lines of SMS carrying qDTY1.1 (SAB) were crossed with DRR-50, an Essentially Derived Variety of SMS carrying qDTY3.1. The SAB lines are taller than SMS due to tight linkage between qDTY1.1 and wild type SD-1. Therefore, F2 generation of crosses were screened for recombinants between SD-1 and qDTY1.1. Phenotyping of 1530 F2 plants representing three F2 populations from 35 F1 hybrids, identified 305 dwarf plants. Three dwarf F2 plants along with three others carrying qDTY1.1 and qDTY3.1 were forwarded to F3 generation. From the six F3 (SABD) lines fourteen pyramided progenies were selected and forward to F4 generation. The six SABD F3 lines SABD-7, SABD-8, SABD-9, SABD-76, SABD-79 and SABD-80 along with parents were evaluated under moisture stress (MS) for various physiological parameters. Chlorophyll and relative water content were more, while canopy temperature and malonaldehyde (MDA) content were lesser in SABD lines compared to parents indicating tolerance under MS. Variance due to genotypes was highly significant for all the yield related traits except test weight. Based on seed morphology, agronomic characters and physiological parameters six superior lines SABD-9-3, SABD-9-2, SABD-9-6, SABD-9-7, SABD-76-2 and SABD-76-6 performing better under MS were identified, which could be released after multi-location evaluation. [ABSTRACT FROM AUTHOR]

Adequate soil moisture around the root zone of the crops is essential for optimal plant growth and productivity throughout the crop season, whereas excessive as well as deficient moisture is usually detrimental. A field experiment was conducted on cotton (Gossipium hirsuttum) with three water regimes (viz. well-watered (control); rainfed after one post-sowing irrigation (1-POSI) and rainfed after two post-sowing irrigations (2-POSI)) in main plots and application of eight osmoprotectants in sub plots of Split plot design to quantify the loss of seed cotton yield (SCY) under high and mild moisture stress. The DSSAT-CROPGRO-cotton model was calibrated to validate the response of cotton crop to water stress. Results elucidated that in comparison of well watered (control) crop, 1-POSI and 2-POSI reduced plant height by 13.5-28.4% and lower leaf area index (LAI) by 21.6-37.6%. Pooled analysis revealed that SCY under control was higher by 1,127 kg ha-1 over 1-POSI and 597 kg ha-1 than 2-POSI. The DSSAT-CROPGRO-cotton model fairly simulated the cotton yield as evidenced by good accuracy (d-stat = 0.92) along with lower root mean square error (RMSE) of =183.2 kg ha-1; mean absolute percent error (MAPE) =6.5% under different irrigation levels. Similarly, simulated and observed biomass also exhibited good agreement with =0.98 d-stat; =533.7 kg ha-1 RMSE; and =4.6% MAPE. The model accurately simulated the periodical LAI, biomass and soil water dynamics as affected by varying water regimes in conformity with periodical observations. Both the experimental and the simulated results confirmed the decline of SCY with any degree of water stress. Thus, a well calibrated DSSAT-CROPGROcotton model may be successfully used for estimating the crop performance under varying hydro-climatic conditions. [ABSTRACT FROM AUTHOR]

Soil moisture stress and low soil fertility are the main constraints to sorghum production in the semi-arid region of northern Ethiopia. A field experiment was conducted in Lasta and Sekota Woreda of Amhara Region, eastern Ethiopia, to evaluate the effect of ridge and tie ridge time on the yield and yield component of sorghum (Sorghum bicolor). The experiment consisted of eight treatments of ridging time & time of tie (Tie-ridging at planting, Ridge at planting tying 2 Weeks After Planting, Ridge at planting tying 4 Weeks After Planting, Tie-ridging 3 Weeks After Planting, Ridging 2 Weeks After planting & tying 4 Weeks After Planting, Ridge 3 Weeks After Planting & tying 6 Weeks After Planting, Tie-ridging 6 Weeks After Planting); including Shilshalo as a control farmer practice which was arranged in a randomized complete block design (RCBD) with three replication. The results of the experiment revealed that the timing of ridging and tie ridging had a significant effect on sorghum yield. The results showed that tie ridging at planting time increased sorghum yield by about 37.9% in Sekota compared to the control (farmer practice), and tie ridging three weeks after planting in Lalibela increased sorghum yield by 30.11% compared to the control (farmer practice). The highest yields of 3.642 tons/ha were obtained with tie ridging at planting in Sekota and 1.903 tons/ha with tie ridging three weeks after planting in Lalibela. Therefore, tie ridging and ridging at planting may be appropriate for sorghum production in the Sekota and sorghum growing areas. However, in Lalibela and sorghum growing areas, tie-ridging three weeks after planting may be appropriate for sorghum production.

Moisture, salinity, heat, and drought are some of the main ecological extremities that recruit anomalous metabolic process which not only effect the plant growth and development but also lessen the crop production. Present eco-friendly approach was intended to explore the integrated role of soil bacteria (Azotobacter vinelandii) on aerenchyma formation, nitrogen assimilation, chlorophyll biosynthesis and photosystem II functionality in low moisture stress environment were studied. Azotobacter were isolated from the date palm around the harsh environment, later it was purified in lab and were used in plants with two different concentration P1= 2.312 CFU mL−1, P2 = 2.316 CFU mL−1. Two-week old treated (P1 and P2) and untreated (P0) plants were exposed to 20 ± 5 % and 45±5 % soil moisture content (SMC) while 75 ± 5 % moisture served as positive control using water holding capacity technique. In stress environment, Azotobacter with two concentrations (P1= 2.312 CFU mL−1, P2= 2.316 CFU mL−1) improved the plant length and biomass production demonstrates lesser declined (2 to 3.9 %) in seedling growth and (21.5 to 39.8 %) in biomass production as compared 31.5 to 49.8 % in control plants (P0). Relative water content (RWC) was greatly sustained in moisture stress due to bacterial applications showing 0.02 to 8.0 % declined as compared 34.9 % in control plants. Likewise lesser decreased (-16.5 to -39.2 %) in osmotic potential was noted in treated plant as compared to control plant (-37.1 to -60.6 %). The sub- optimal stress from moderate to severe instigated significant upsurge of energy loss in plants. The energy loss indicators like non-photochemical quenching coefficient (qN) and non-photochemical quenching (NPQ) were relatively high (4.1 to 12.9 % and 33.26 to 47.64 %) in Po as compared to P1 and P2 (0.9 to 1.9 % and 1.3 to 14.2 %) plants. Moreover, application of azotobacter (P1 and P2) also upregulated quantum yield of electron transport (jEo,), the efficiencies of light reaction (φPo / (1- φPo), and biochemical reaction (ψo /(1- ψo) in sub-optimal environment. The upregulation in light harvesting efficiency enhance nitrogen assimilation showing lesser declined in nitrite (21.1 to 9.3 %) and nitrate content (50.0 to 24.0%) in P1 and P2 plants compared to control plants (P0). It was noted that P2 treated plants showed lesser declined in protein content (22 %) corresponding with 8.0 % in nitrite reductase (NIR) and 5.1 % in nitrate reductase (NR) activities. The current finding suggested that the application of azotobacter improve growth and biomass production due sustained photosystem II functionality and nitrogen assimilation under moisture environment. Further, Azotobacter facilitates the aerenchyma formation in plants roots under stress condition enabling gaseous exchange in roots. Application of azotobacter in moisture environment seems to be a promising and eco-friendly solution for sustainable agriculture which not only provide an alternative beside chemical fertilizers but also protect plant against low moisture stress consequences.

Moisture stress is among the major banes against production of rice at self-sufficient level. Different growth stages of rice are affected differently by moisture stress. Therefore, we conducted a study to determine the potential of seed priming in alleviating moisture stress in rice at tillering stage. The priming treatments used were 100mM calcium chloride dehydrate, 40% (w/v)polyethylene glycol (PEG)6000 and 100ppm kinetin. Pre-germination which is the farmers’ practice was used as the control. We assessed the plants on number of tillers, productive tillers, tillering efficiency and sterility, number of spikelets, filled spikelets, 100 grain weight, grain yield, harvest index, chlorophyll and proline concentration, net photosynthesis, stomatal conductance, inter cellular carbon dioxide and transpiration rate. We found that one day priming with 100ppm kinetin conferred better tolerance against moisture stress and produced higher grain yield than the rest treatments at tillering stage. The outcome of this research is that by using one-day priming with 100ppm kinetin for production of MR219, we can save water at tillering stage and use the saved water for nurturing the plants at booting stage which is ultra-sensitive to water stress.

Adequate soil moisture around the root zone of the crops is essential for optimal plant growth and productivity throughout the crop season, whereas excessive as well as deficient moisture is usually detrimental. A field experiment was conducted on cotton (Gossipium hirsuttum) with three water regimes (viz. well-watered (control); rainfed after one post-sowing irrigation (1-POSI) and rainfed after two post-sowing irrigations (2-POSI)) in main plots and application of eight osmoprotectants in sub plots of Split plot design to quantify the loss of seed cotton yield (SCY) under high and mild moisture stress. The DSSAT-CROPGRO-cotton model was calibrated to validate the response of cotton crop to water stress. Results elucidated that in comparison of well watered (control) crop, 1-POSI and 2-POSI reduced plant height by 13.5–28.4% and lower leaf area index (LAI) by 21.6–37.6%. Pooled analysis revealed that SCY under control was higher by 1,127 kg ha−1 over 1-POSI and 597 kg ha−1 than 2-POSI. The DSSAT-CROPGRO-cotton model fairly simulated the cotton yield as evidenced by good accuracy (d-stat ≥ 0.92) along with lower root mean square error (RMSE) of ≤183.2 kg ha−1; mean absolute percent error (MAPE) ≤6.5% under different irrigation levels. Similarly, simulated and observed biomass also exhibited good agreement with ≥0.98 d-stat; ≤533.7 kg ha−1 RMSE; and ≤4.6% MAPE. The model accurately simulated the periodical LAI, biomass and soil water dynamics as affected by varying water regimes in conformity with periodical observations. Both the experimental and the simulated results confirmed the decline of SCY with any degree of water stress. Thus, a well calibrated DSSAT-CROPGRO-cotton model may be successfully used for estimating the crop performance under varying hydro-climatic conditions.

Split plot design experiments were conducted to assess the performance of growth regulating compounds for mitigating moisture stress and the incidence of Brown Plant Hopper (BPH) in rice. The main plot treatments (4) comprised moisture stress free control (M1), moisture stress during panicle initiation stage alone (M2), moisture stress during flowering stage alone (M3), and moisture stress during both panicle initiation and flowering stages (M4). The sub-plot treatments (5) were foliar application of growth regulating compounds including chlormequat chloride at 200 ppm (S1), mepiquat chloride at 200 ppm (S2), brassinolide at 0.1 ppm (S3), pink pigmented facultative methylotrophs (PPFM) at 1% (S4), and no spray control (S5). The reduced plant growth attributes were registered under moisture stress at both panicle initiation and flowering stages. The spraying of 1% PPFM during the flowering or both at panicle initiation and flowering stages led to better performance than the other treatments. Also, spraying 1% PPFM brought down the population of BPH to a considerable level during both years of experiments. This suggests that spraying 1% PPFM in the post-flowering stage helps to mitigate the ill effect the moisture stress and BPH incidence. [ABSTRACT FROM AUTHOR]

Understanding how seed functional traits interact with environmental factors to determine seedling recruitment is critical to assess the impact of climate change on ecosystem restoration. This study focused on the effects of environmental factors on the mother plant during early plant life history stages and during seed development. Desmodium brachypodum A. Gray (large tick trefoil, Fabaceae) was used as a model species. Firstly, this study analyzed seed germination traits in response to temperature and moisture stress. Secondly, it investigated how seed burial depth interacts with temperature and soil moisture to influence seedling emergence traits. Finally, it determined if contrasting levels of post-anthesis soil moisture could result in changes in D. brachypodum reproductive biology and seed and seedling functional traits. The results showed that elevated temperature and moisture stress interacted to significantly reduce the seed germination and seedling emergence (each by >50%), while the seed burial improved the seedling emergence. Post-anthesis soil moisture stress negatively impacted the plant traits, reducing the duration of the reproductive phenology stage (by 9 days) and seed production (by almost 50%). Unexpectedly, soil moisture stress did not affect most seed or seedling traits. In conclusion, elevated temperatures combined with low soil moisture caused significant declines in seed germination and seedling emergence. On the other hand, the reproductive output of D. brachypodum had low seed variability under soil moisture stress, which might be useful when sourcing seeds from climates with high variability. Even so, a reduction in seed quantity under maternal moisture stress can impact the long-term survival of restored plant populations.

IntroductionUnder a changing climate, the fragile ecosystems of the Eastern Himalayas (EH) are persistently challenged by prolonged dry spells and erratic rainfall. Identification of suitable high-yielding crops with higher moisture stress tolerance and adaptability is paramount for the region. Although the region received a good amount of rainfall in the rainy season, the winter months, viz., November to March, rarely received any rain. Even within the rainy season, there are several intermittent drought spells that hinder crop productivity.MethodsThe present study has used field and microcosm experiments to assess the year-round cultivation potential and extent of moisture stress tolerance in the lesser-known buckwheat crop of the region.Results and discussionSowing of buckwheat from mid-September to mid-December produced better grain yield, the highest being when sowing in October (9.83 q ha−1) and the crop was found suitable to grow all through the year for higher green biomass (12.6–38.4 q ha−1). The moisture stress tolerance of buckwheat was significantly enhanced by increased total root length and root surface area by 12.4 and 34.7%, respectively. Increased photo-protective carotenoids, chlorophyll b, and favorable stomatal attributes with substantial epicuticular wax have significantly improved the moisture stress tolerance of Buckwheat. In addition, leaf proline was found 25.4% higher and total soluble protein, reducing sugar, and cell membrane stability were found 29.2, 38.1, and 36.5% lower compared to the control, respectively. A significantly lower rate of water loss (25.6%) with its stomatal and non-stomatal adaptations and versatile pollen structural traits under moisture stress over control, make the buckwheat crop potentially more stress tolerant and economical crop for EH of India.

Water availability is the dominant driver of microbial community structure and function in desert soils. However, these habitats typically only receive very infrequent large-scale water inputs (e.g., from precipitation and/or run-off). In light of recent studies, the paradigm that desert soil microorganisms are largely dormant under xeric conditions is questionable. Gene expression profiling of microbial communities in desert soils suggests that many microbial taxa retain some metabolic functionality, even under severely xeric conditions. It, therefore, follows that other, less obvious sources of water may sustain the microbial cellular and community functionality in desert soil niches. Such sources include a range of precipitation and condensation processes, including rainfall, snow, dew, fog, and nocturnal distillation, all of which may vary quantitatively depending on the location and geomorphological characteristics of the desert ecosystem. Other more obscure sources of bioavailable water may include groundwater-derived water vapour, hydrated minerals, and metabolic hydro-genesis. Here, we explore the possible sources of bioavailable water in the context of microbial survival and function in xeric desert soils. With global climate change projected to have profound effects on both hot and cold deserts, we also explore the potential impacts of climate-induced changes in water availability on soil microbiomes in these extreme environments. [ABSTRACT FROM AUTHOR]

A field investigation was made at the Tamil Nadu Agricultural University farm in Coimbatore during the late Kharif 2019 and late Rabi 2019-20 seasons to quantify the impact of induced moisture stress (MS) at critical stages (10, 15, 20 & 25 days from panicle initiation and flowering) on physiological traits and yield of rice. The experiment was laid-out in randomized complete block design (RCBD) with three replications. During both seasons, physiological traits (photosynthetic rate, stomatal conductance, transpiration rate and chlorophyll index) were recorded after the MS period (10, 15, 20 and 25 days) at both critical stages. The experimental results revealed that MS of any period and any stage (panicle initiation and flowering) reduced the values of all physiological traits, grain and straw yields in both seasons. The MS period of 25 days from panicle initiation significantly reduced all physiological parameters, including rice yield. [ABSTRACT FROM AUTHOR]

Highlights Application of biochar under wet moisture condition did not impact coconut seedling growth. Under dry moisture BC-Gly enhanced crop growth similar to wet treatments and plant P uptake. AMF growth was not impacted by biochar amendment aside from a stimulation in dry soil by BC-Gly. The N rich BC-Gly likely provides N to the plants via fungi stimulated biochar decomposition.

Background and objectives: A proper understanding of crop yield and corresponding water consumption is important to reach the sustainable agriculture. Water footprint (WF) is one of the indicators for describing water consumption and water use efficiency so that its accurate estimation in different climates and cropping systems (i.e. rainfed and irrigated) could be effective in managing water resources. WF consists of four components included green water, blue water, gray water, and white water. The magnitude of WF and its components is notably affected by deferent factors such as soil type, climate, and water management practices. Accordingly, the current study aimed to assess water footprint and its components in various irrigated and rainfed wheat agro-ecosystems of Iran. Materials and methods: In the current study, water footprints and its components (blue, green, gray, and white waters) were simulated for irrigated and rainfed wheat agro-ecosystems in six locations in Iran (Ardebil, Hamedan, Sanandaj, Tabriz, Urmia, and Zanjan) during the 37-year period (1980-2016) using APSIM (Agricultural Production Systems sIMulator) crop model. To do this, four inputs for the crop model including crop characteristics (i.e. genetic coefficients), climatic data (i.e. maximum and minimum temperatures, rainfall, and solar radiation), soil characteristics (i.e. soil water content at wilting point and field capacity, saturation water content and bulk density), and management practices (i.e. sowing date, nitrogen fertilizer, irrigation, and etc.) were gathered to run the crop model. Outputs from the model were used to estimate WF components. The outputs included grain yield, cumulative net irrigation, and evapotranspiration in irrigated and rainfed systems, respectively. Results: The results showed that grain yield and total WF were 2.4 t ha-1 and 1498 m³ t -1 for rainfed, and 5.7 t ha-1 and 1393 m³ t -1 for irrigated systems. The magnitude of WF was not only associated with type of cropping system (i.e. irrigated and rainfed) but also strongly region-dependent. Shifting from rainfed wheat cultivation to irrigated one increased WF of +15.2, +14.6, +28.1 % for Tabriz, Urmia, and Zanjan and decreased WF of -5.94, -9.03, and -9.12 % for Ardebil, Hamedan, and Sanandaj, respectively. In irrigated wheat systems, the shrare of green, blue, gray, and white waters in total WF simulated by 32.3, 24.2, 20.9, and 22.6 %, respectively. However, in rainfed wheat systems, the shrare of green and gray waters in total WF estimated by 90.3 and 9.60 %, respectively. Conclusion: The findings of the current research showed that shifting from irrigated to rainfed cultivation of wheat in some areas of northwestern Iran (i.e. Ardebil, Hamedan, and Sanandaj) could lead to a significant reduction in blue water consumption (less irrigation) and subsequently increase sustainability in these areas. [ABSTRACT FROM AUTHOR]

The sunflower (Helianthus annus L.) is a vital oilseed crop exposed to drought globally. A vast proportion of research is devoted to the naturally occurring microbes and their interaction with plants to alleviate stress consequences. Halophilic bacterial strains, i.e., Bacillus cereus KUB-15 (accession number NR 074540.1), KUB-27 (accession number NR 074540.1), and Bacillus licheniformis strain AAB9 (accession number MW362506), were isolated. Later, isolated strains were used for sunflower through inoculation. Plants were allowed to grow, and thirty-days-old plants were exposed to fixed moisture stress (40–45%). The functionality of photosystem II, light-harvesting ability, and physiological tolerance of cultivars were examined. Bacterial strains B. licheniformis sustained substantial electron flow in between photosystem II (PS II) and photosystem I (PS 1) that not only favored the passable photosynthetic performance but also enhanced antioxidant enzyme activity under stress condition. Compared to other halophilic strains, Bacillus licheniformis did manage reasonable relative water content (RWC), chlorophyll content index (CCI) and biomass production under stress condition. In comparison to both sunflower cultivars, bacterial inoculation was greatly restored growth and photosynthetic performance in Agsun-5264 than S-278 under moisture stress environment. Hence, it is suggested that that bacterial strain and plants cultivar compatibility are essential aspect for sustainable agriculture production. [Display omitted] • Halophilic soil bacteria sustained quantum harvesting and energy flow. • Bacterial strains improved the oxygen-evolving complex activity. • PS II functionality and physiological tolerance are concurrent. [ABSTRACT FROM AUTHOR]

A microplot experiment was conducted to study the influence of rhizobia, Bradyrhizobium liaoningense and arbuscular mycorrhizal (AM) fungus, Ambispora leptoticha on the growth and yield performance of a drought susceptible soybean cultivar. MAUS 2 and a drought tolerant cultivar, DSR 12 under control and water stressed conditions. Accordingly, the physiological, growth and yield parameters including the inoculated microflora were significantly higher in inoculated plants compared to un-inoculated plants of both the cultivars in control and stressed conditions. Total dry biomass was significantly higher in inoculated plants with 88% in MAUS 2 and 95% in DSR 12 over un-inoculated plants under water stress condition. Under drought condition, dual inoculation has increased the seed weight by 32% and 25% in MAUS 2 and DSR 12 cultivars respectively over the un-inoculated plants suggesting that the dual inoculation is more useful in imparting stress tolerance in susceptible genotype. Further, the yield level of inoculated plants under stress was almost similar to the un-inoculated irrigated control plants suggesting the role of dual inoculum (rhizobia and mycorrhiza) in alleviating the stress effect. ANOVA interaction analysis also showed significant difference between the treatments (T), cultivars (C) and their interaction (T × C) on growth and yield parameters. This suggests that, there is a significant positive microbial inoculation effect between the treatments and the cultivars. Overall, our study revealed that, dual inoculation has improved the stress tolerance of soybean cultivars with sustained productivity under drought condition. [ABSTRACT FROM AUTHOR]

Peatlands are globally important long‐term sinks of atmospheric carbon dioxide (CO2). However, there is concern that climate change‐mediated drying will reduce gross primary productivity (GPP) and increase ecosystem respiration (ER) making peatlands vulnerable to a weaker carbon sink function and potential net carbon loss. While large and deep peatlands are usually resilient to moderate summer drying, CO2 exchange in shallow Boreal Shield peatlands is likely more sensitive to drying given the reduced groundwater connectivity and water storage potential. To better understand the carbon cycling responses of Boreal Shield peatlands to meteorological conditions, we examined ecohydrological controls on CO2 fluxes using the eddy covariance technique at a shallow peatland during the summer season for 5 years, from 2016–2020. We found lower GPP in dry summer years. Mean summer water table depth (WTD) was found to be significantly correlated with summer total net ecosystem CO2 exchange (R2 = 0.78; p value = 0.046) and GPP (R2 = 0.83; p value = 0.03), where wet summers with a WT close to the peat surface sequestered more than twice the amount of CO2 than dry summers. Our findings suggest that shallow Boreal Shield peatland GPP may be sensitive to climate‐mediated drying as they may switch to a net CO2 source in the summer season when WTDs exceed a critical ecohydrological threshold for a prolonged period of time. Plain Language Summary: Peatlands take in carbon from the atmosphere and store it in the ground as peat, a process that helps to regulate climate change. Peatlands in the Boreal Shield are positioned in bedrock basins. Their water table (WT) is controlled by precipitation, which can trigger water flow over the bedrock between wetland ecosystems. Due to this unique setting, we expected Boreal Shield peatlands to be more sensitive to differences in growing season meteorological conditions from year to year. We used 5 years of carbon dioxide (CO2) exchange measurements between land and atmosphere during the summer season in a Boreal Shield peatland in Ontario, Canada. We found the peatland vegetation took up more CO2 from the atmosphere during summers with more rain which keeps the WT in the peatland closer to the peat surface. The peatland took up less CO2 when the summer was dry. Our findings provide insight into how Boreal Shield peatlands are responding to summer droughts under current climate conditions. Key Points: Summers with higher rainfall (and lower P‐PET) maintain a water table near the peat surface and have greater net carbon dioxide (CO2) uptakeInterannual differences in summer net ecosystem CO2 exchange are attributable to changes in summer gross primary productionShallow Boreal Shield peatlands may switch to a net carbon source in the summer season [ABSTRACT FROM AUTHOR]

Soil moisture stress is one of the most serious aspects of climate change. Selenium (Se) is regarded as an essential element for animal health and has been demonstrated to protect plants from a number of abiotic challenges; however, our knowledge of Se-regulated mechanisms for enhancing crop yield is limited. We investigated the effects of exogenous Se supplementation on physiological processes that may impact wheat productivity during soil moisture stress. The plants were grown in plastic containers under screen-house conditions. The experiment was laid out in CRD consisting of three soil moisture regimes, i.e., control (soil moisture content of 12.5 ± 0.05%), moderate (soil moisture content of 8.5 ± 0.05%), and severe moisture stress (soil moisture content of 4.5 ± 0.05%). Selenium was supplied using sodium selenite (Na2SeO3) through soil application before sowing (10 ppm) and foliar application (20 ppm and 40 ppm) at two different growth stages. The foliar spray of Se was applied at the vegetative stage (70 days after planting) and was repeated 3 weeks later, whereas the control consisted of a water spray. The water status, photosynthetic efficiency, and yield were significantly decreased due to the soil's moisture stress. The exogenous Se application of 40 ppm resulted in decreased negative leaf water potential and improved relative water contents, photosynthetic rate, transpiration rate, and stomatal conductance in comparison to the control (without selenium) under water shortage conditions except the plants treated with soil application of selenium under severe moisture stress at 70 DAS. Subsequently, Se-regulated mechanisms improved 100 seed weight, biological yield, and seed yield per plant. We suggest that Se foliar spray (40 ppm) is a practical and affordable strategy to increase wheat output in arid and semi-arid regions of the world that are experiencing severe water shortages. [ABSTRACT FROM AUTHOR]

Non-invasive techniques such as RGB, thermal imaging, and optical sensing can provide information on plant water stress before it occurs. In the present study, the maize crop (Var. DMRH 1301) was cultivated with three different sowing dates (1, 15, and 30 June) under rainfed condition. The RGB and thermal images along with crop growth parameters were recorded periodically along with soil moisture in maize. A deep learning model (DarkNet53) was applied on RGB as well as thermal images for the identification of water stress. The occurrence of rainfall and thereby soil moisture had a significant effect on crop canopy temperature under different dates of sowing. The canopy temperature histogram under water stress showed bimodal distribution whereas unimodal distribution was observed under non-stress condition. The maximum accuracy of the DarkNet53 model at 20 epochs and 8 batch size for the identification of water stress in RGB and thermal imagery was 94.1 and 99.6%, respectively. The testing accuracy of identification of water stress for RGB imagery were 94.1, 90.5, and 92.3% and for thermal imagery 95.7, 91.5, and 99.6% in early, timely and late sown maize, respectively. Overall, thermal imagery input had higher accuracy for water stress identification. The present study showed that non-destructive, rapid vision-based techniques using digital imagery can helpto characterize plant growth, water stress, and thereby, yield. [ABSTRACT FROM AUTHOR]

The present study was conducted to identify the nature and magnitude of genetic variability, correlation and path coefficient analysis among forty eight fenugreek genotypes under normal and moisture stress conditions in a randomized block design with three replications. The pooled analysis of variance indicated a significant interaction between genotypes and environments for majority of the traits. The analysis of variance for individual environments indicated the existence of significant variability for all the characters, justifying the selection of genotypes for the study. The values of phenotypic coefficient of variation were higher than the genotypic coefficient of variation indicated effect of environment on expression of all characters. The satisfactory estimates of coefficients of variation were recorded for pods per plant and seed yield per plant. High heritability coupled with high genetic advance as a percentage of mean was observed for pods per plant in both environments. The correlation and path coefficient analysis showed that pods per plant had a positive correlation with a high direct effect on seed yield. The results indicated that selection may be worthwhile for pods per plant due to lesser influence of environment and predominance of additive gene action in the genotypes for increasing seed yield.

Drylands cover about 40% of the terrestrial surface and are sensitive to climate change, but their relative contributions to global vegetation greening and productivity increase in recent decades are still poorly known. Here, by integrating satellite data and biosphere modeling, we showed that drylands contributed more to global gross primary productivity (GPP) increase (65% ± 16%) than to Earth greening (33% ± 15%) observed during 1982–2015. The enhanced productivity per unit leaf area, i.e., light-use efficiency (LUE), was the mechanism behind this pattern. We also found that LUE was more sensitive to soil moisture than to atmospheric vapor pressure deficit (VPD) in drylands, while the opposite was observed (i.e., LUE was more sensitive to VPD) in humid areas. Our findings suggest the importance of using different moisture stress metrics in projecting the vegetation productivity changes of dry versus humid regions and highlight the prominent role of drylands as key controllers of the global carbon cycle. [ABSTRACT FROM AUTHOR]

Moisture stress induced by intra-season and terminal dry spells has been addressed as principal constraint for maize cultivation across the rainfed environment. A multi-location field experiment was conducted, to investigate the influence of different levels of foliar-applied thiourea along with the variation across prevalent planting techniques and in situ moisture conservation measures on growth, physiology, hormonal changes, phenology, antioxidative defence system, grain yield, and biochemical traits of moisture-stressed rainfed maize. Three dry spells were assessed during pre-anthesis and grain-filling stages. Results revealed that crop growth and productivity was influenced negatively by dry spells, but the extent of reduction varied with variations across plant growth regulators and planting methods. Crop growth and grain yield was lowest in unsprayed and flat sowing, whereas significant improvements were recorded with foliar application of 1000 ppm thiourea (14.6% and 11%) along with ridge sown and mulched (16.7% and 13.8%) treatments. Tasselling and physiological maturity were earliest in flat sowing and unsprayed, whereas significant improvements across proline and relative leaf water content were observed in thiourea 1000 ppm and ridge sowing with mulch treatments in which leaf chlorophyll content index (35.5), leaf area index (4.42 and 4.44) and starch deposition (71.1% and 70.3%) were also highest ,but total sugars accumulation (2.41% and 2.60%) and protein degradation (10.9% and 11.0%) were lowest. In crux, ridge sowing in association with mulch and foliar application of thiourea 1000 ppm mitigated moisture stress in rainfed maize with amelioration across plant's defence through elaborated antioxidative defence system, compatible osmolyte accumulation, starch biosynthesis and their assimilation into developing sink organs for achieving the highest productivity levels. [ABSTRACT FROM AUTHOR]