Water Stress Treatments Research Articles

Cowpea (Vigna unguiculata L. Walp) morpho-physiological and yield responses to chemical, organic, and biofertilizers at various watering levels utilizing drip irrigation system

ABSTRACT The infertility of sandy soil hampers the growth of many crops. Typically, chemical fertilizers are used to handle this issue, but they are expensive and have deleterious implications on the ecosystem. A two-year field investigation was carried out on cowpea cultivated in sandy soil to assess the effects of different watering levels (70, 80, 90, and 100% of the actual irrigation requirements), chemical fertilizers, organic fertilizers, and biofertilizer (Bradyrhizobium sp.), and their combinations on the morpho-physiological traits and yield of cowpea (Vigna unguiculata L. Walp, cv. Giza 18). Overall, the findings showed that cowpea osmoregulatory molecules (sugars, proteins, and proline) demonstrated greater accumulation, with the content depending on the watering level. The applied fertilizers demonstrated improved cowpea performance at the regular watering level, with chopped potato tops outperforming other fertilizer formulations. Furthermore, the combination of water stress treatments and fertilizer formulations was impactful in relieving the detrimental consequences of water stress as it enhanced plant growth performance, production efficiency, metabolic homeostasis, nutritional value, and mineral ions composition. Subsequently, our results demonstrated agro-wastes, particularly chopped potato tops, could be an effective substitute for chemical fertilizers in sandy soils to sustainably increase soil fertility as well as cowpea yield performance.

Hydrologic Consistency of Multi-Sensor Drought Observations in Forested Environments

Drought can have significant impacts on forests, with long periods of water scarcity leading to water stress in trees and possible damages to their eco-physiological functions. Satellite-based remote sensing offers a valuable tool for monitoring and assessing drought conditions over large and remote forested regions. The objective of this study is to evaluate the hydrological consistency in the context of drought of precipitation, soil moisture, evapotranspiration, and land surface temperature observations against in situ measurements in a number of well-monitored sites in New Zealand. Results showed that drought indicators were better captured from soil moisture observations compared to precipitation satellite observations. Nevertheless, we found statistically significant causality relationships between the multi-sensor satellite observations (median p-values ranging from 0.001 to 0.019), with spatial resolution appearing to be an important aspect for the adequate estimation of drought characteristics. Understanding the limitations and capabilities of satellite observations is crucial for improving the accuracy of forest drought monitoring, which, in turn, will aid in sustainable forest management and the development of mitigation and adaptation strategies in the face of changing climate conditions.

Foliar application of SiO2 nanoparticles to increase shallot production under water stress as an effort to mitigate climate change

Global climate change has resulted in environmental stress which has the potential to reduce the production of various agricultural commodities. One of the reasons for the low production of shallot is because cultivated in land with limited water. An effort to minimize the impact of water stress on shallots is to use SiO2 nanoparticles. This study aims to determine the role of SiO2 nanoparticles to increase production of shallot under water stress. This research was conducted at the greenhouse of the Faculty of Agriculture from December 2022 to March 2023, using randomized block design. The first factor is water stress (80%, 60% and 40% field capacity) and the second factor is the concentration SiO2 nanoparticles (0 g/l, 6 g/l, 12 g/l and 18 g/l). The results showed the water stress treatment had significant effect reduced number of tubers and fresh and dry weight of tubers, the application of SiO2 nanoparticles had significant effect increased the number of tubers and fresh and dry weight of tubers. Interaction of application SiO2 nanoparticles and water stress conditions had a significant effect on increased the number of tubers in the combination of 80% field capacity with SiO2 nanoparticles concentration 12 g/l.

Cavitron extraction of xylem water suggests cryogenic extraction biases vary across species but are independent of tree water stress

AbstractCryogenic vacuum distillation (CVD) is a widely used technique for extracting plant water from stems for isotopic analysis, but concerns about potential isotopic biases have emerged. Here, we leverage the Cavitron centrifugation technique to extract xylem water and compare its isotopic signature to that of CVD‐extracted bulk stem water as well as source water. Conducted under field conditions in tropical northern Australia, our study spans seven tree species naturally experiencing a range of water stress levels. Our findings reveal a significant deuterium bias in CVD‐extracted bulk stem water when compared to xylem water (median bias −14.9‰), whereas xylem water closely aligned with source water (median offset −1.9‰). We find substantial variations in deuterium bias among the seven tree species (bias ranging from −19.3‰ to −9.1‰), but intriguingly, CVD‐induced biases were unrelated to environmental factors such as relative stem water content and predawn leaf water potential. These results imply that inter‐specific differences may be driven by anatomical traits rather than tree hydraulic functioning. Additionally, our data highlight the potential to use a site‐specific deuterium offset, based on the isotopic signature of local source water, for correcting CVD‐induced biases.

Categorization of Sugar Beet Varieties for Water Saving in Sandy Soils Using Factor Analysis Scores

AbstractWater shortage in dry and semi-arid regions is a major agricultural challenge. This study investigated the performance of ten imported monogerm sugar beet varieties under continuous deficiency irrigation using a drip system on a private farm in the Wadi El-Natrun region, El-Beheira Governorate, Egypt, during two growing seasons, 2021/2022 and 2022/2023. The study utilized a novel method, a crossbar graph, to effectively visualize statistical data. The results showed significant interaction effects between sugar beet varieties and water deficit levels for all traits, indicating varying responses of the varieties to different levels of drought stress (75% and 55%). Drought stress levels (75% and 55%) had an adverse effect on the root yield of the ten varieties of sugar beet that were investigated. The exploratory factor analysis was applied to investigate and describe the relationship between ten different varieties of sugar beet and water stress treatments. Varieties Symbol, Stikhiyn, Volua, and Klara were characterized as moderate and tolerant with high performance, and they received the highest score in factor analysis. These varieties are recommended for cultivation under moderate and severe stress conditions. Factor analysis scores can be used as selection criteria for sugar beet varieties.

The Effect of Water Availability on the Carbon Content of Grain and Above- and Belowground Residues in Common and Einkorn Wheat.

The carbon (C) fixed by crops, which is exported with harvest and retained as postharvest residues in a field, is important for calculating the C balance. The aim of this study was to determine the effect of water availability on the C content in whole wheat plants. In a three-year field trial, the weights of grain, straw, chaff, stubble, and roots of two cultivars of winter wheat (Triticum aestivum L.) and one cultivar of einkorn wheat (Triticum monococcum L.) and their carbon contents were determined in water stress, irrigation, and rain-fed control treatments. The water availability, year, and cultivar had a significant influence on the C content in aboveground plant parts, but the effect of water on grain C was weak. The C content decreased with irrigation and increased with drought, but the differences were small (at most, 3.39% in chaff). On average, the C contents of grain, straw, chaff, and roots reached 45.0, 45.7, 42.6, and 34.9%, respectively. The amount of C exported with grain and left on the field in the form of postharvest residues depended on the weight of the total biomass and the ratio of grain to straw and residue. Whole plant C yield reached 8.99, 7.46, and 9.65 t ha-1 in rain-fed control, stressed, and irrigated treatments, respectively, and 8.91, 9.45, and 7.47 t ha-1 in Artix, Butterfly, and Rumona, respectively. Irrigation significantly increased the C content in grain and straw (but not in chaff, stubble, and roots) in comparison with water shortage conditions. On average, a grain yield of 1 t ha-1 corresponded to an average export of 0.447-0.454 t C ha-1 in the grain of all cultivars and inputs of 0.721, 0.832, and 2.207 t C ha-1 of residue to the soil in the form of straw and postharvest residue in the two cultivars of common wheat and one of einkorn. The results of the study provided reliable data for the calculation of the C balance of wheat under conditions of different water availability.

Effect of Water Stress and Levels of Bio-Organic Fertilizers on Water Productivity and Potato Solanum tuberosum L. Yield

A field experiment was conducted at the University of Baghdad, Al-Jadriya in the spring season of 2021 for the potato crop under the influence of organic biofertilizers and water stress. Three levels of bio-organic fertilizers were used 0 (OM0), 1 (OM1) and 1.5 (OM2) ton ha-1 and three levels of irrigation 30 (I-30), 50 (I-50) and 75 (I-75) % water depletion were available to evaluate the role of bio-organic fertilizer and water stress in production functions and water use efficiency. I-30 treatment showed the highest water consumption ranging between 468 and 486 mm season-1 and decreased to 355-436 mm with water stress treatments I-75. The values of water consumption varied according to the levels of bio-organic fertilizer. The percentage of decrease in water consumption was 1.49 and 3.66% at low stress and reached 6.37% at high stress (I-75) compared to OM0. Both treatments I-30 and I-50 gave the same yield. Bio-organic fertilization led to an increase in the average yield of tubers 32.8 and 41.9% for both OM1 and OM2 compared to OM0. The production functions indicate that the yield increases by 0.057 ton ha-1 mm-1 of added water, and the water depth must be greater than 64.2 mm to obtain a yield that is 1.96 ton ha-1 more (significant limit) than the treatments in the experiment (1.96=0.057(Irr.). )-1.70). Fertilizer levels are higher than 1.9 ton ha-1 to obtain a higher yield of tubers by 26.29 tons/ha and the efficiency of water use is nil according to the water use function when the water consumption is higher than 692.7 mm. The response factor decreased when adding bio-organic fertilizer compared to OM0, which means that plants were not affected significantly under water stress conditions.

Detecting the Short-Term Effects of Water Stress on Radiata Pine Physiology Using Thermal Imagery

Despite the utility of thermal imagery for characterising the impacts of water stress on plant physiology, few studies have been undertaken on plantation-grown conifers, including the most widely planted exotic species, radiata pine. Using data collected from a pot trial, where water was withheld from radiata pine over a nine-day period, the objectives of this study were to (i) determine how rapidly key physiological traits change in response to water stress and (ii) assess the utility of normalised canopy temperature, defined as canopy temperature–air temperature (Tc–Ta), for detecting these physiological changes. Volumetric water content remained high in the well-watered control treatment over the course of the experiment (0.47–0.48 m3 m−3) but declined rapidly in the water stress treatment from 0.47 m3 m−3 at 0 days after treatment (DAT) to 0.04 m3 m−3 at 9 DAT. There were no significant treatment differences in measurements taken at 0 DAT for Tc–Ta, stomatal conductance (gs), transpiration rate (E) or assimilation rate (A). However, by 1 DAT, differences between treatments in tree physiological traits were highly significant, and these differences continued diverging with values in the control treatment exceeding those of trees in the water stress treatment at 9 DAT by 42, 43 and 61%, respectively, for gs, E and A. The relationships between Tc–Ta and the three physiological traits were not significant at 0 DAT, but all three relationships were highly significant from as early as 1 DAT onwards. The strength of the relationships between Tc–Ta and the three physiological traits increased markedly over the duration of the water stress treatment, reaching a maximum coefficient of determination (R2) at 7 DAT when values were, respectively, 0.87, 0.86 and 0.67 for gs, E and A. The early detection of changes in tree physiology from 1 DAT onwards suggests that thermal imagery may be useful for a range of applications in field-grown radiata pine.

Identification of the Effect of Water Stress on Yield Production and Evaluation of the Nutrient Content of Garut Tubers and Flour

Arrowroot tubers (Maranta Arundinace L.) are a tuber plant that has potential as a source of carbohydrates. Arrowroot tuber plants have the potential to adapt well to various environmental conditions including water stress. The aim of this research was to identify the effect of water stress on yield production (number, weight, length and diameter) and evaluate the nutritional content of arrowroot tubers. This research used a Completely Randomized Design (CRD) with 7 water stress treatments, namely (P1) 15 days of waterlogging, (P2) 10 days of waterlogging, (P3) 5 days of waterlogging, (P4) daily watering, (P5) watering every 5 days, (P6) watering every 10 days, and (P7) watering every 15 days which was repeated in 2 experimental repetitions and 2 measurement repetitions. The results of the research showed that there was no decrease in yield in treatments P1 to P3, however in treatments P6 and P7 there was a difference in the yield of lower tuber weight compared to the daily watering treatment (P4) and the once every 5 days watering treatment (P5). Treatment The results of proximate analysis of arrowroot tubers with the best yield production (P5) showed that the water, ash, fat, protein and carbohydrate content of fresh tubers were respectively 69.82%, 1.47%, 0.21%, 0, 45% and 28.15%, while arrowroot flour is 2.28%, 4.77%, 0.33%, 1.47% and 91.16%. The results of this research provide information that arrowroot plants can be planted on land that has the potential to be flooded during the arrowroot growing season, but arrowroot plants require sufficient water to optimize their production. The high carbohydrate content of arrowroot tubers reflects its potential as an alternative food source to replace wheat and rice.

Seed priming of stored seeds on seed germination, vegetative performance, flowering, and proline content in chili under water stress condition

Chili seeds mostly have been stored for a long period; therefore, the seed quality may be affected. Prior to planting, reinvigoration by priming treatments becomes an important treatment. The purpose of this study was to evaluate how priming affected seed germination, vegetative performance, flowering, and proline content in chili cv. "Inata Agrihorti" under water stress treatment. The research was carried out in the Physiology Laboratory and Shade House in Batu East Java, Indonesia from December 2022 to March 2023, A factorial Randomized Block Design with three replications was set up in this study that consisted of two factors. First factor was stored seeds (2 and 5 years) duration of chili cv. Inata Agrihorti, and the second factor was priming treatments (Phenol Ethyl Glycol 6000, Gibberellic acids, Phenol Ethyl Glycol 6000 + Gibberellic acids, and distilled water as a control). The reinvigoration of stored seeds by priming treatments significantly improved germination percentage, germination time, root length, and proline content of early seedlings’ stages either under water stress or distilled water treatment as a control. The interaction of priming treatment and stored seeds was also recorded in improving the vegetative performance, flower number, and proline content of chili plants derived from reinvigorated seeds under water stress or normal watering treatment. Under water stress and/or normal conditions, primed seeds of 2-year-old stored seeds produced larger values of these variables than primed seeds of 5-year-old stored seeds. To improve yield, seed invigoration of stored seeds of chili cv Inata Agrihort through - 1.5 MPa Phenol Ethyl Glycol 6000 treatment was recommended.

Effect of Mycorrhizae Inoculation and Spraying with Amino Acids on some Yield Traits and Leaf Proline Content of Corn Plant

A field experiment was conducted in the spring season in the field of the College of Agriculture of the University of Babylon to study the effect of mycorrhizae inoculation and spraying with amino acids on some growth indicators of corn according to The Randomized Complete Block Design (RCBD) using three factors. The second factor is the amino acids with four levels (0, 200 proline, 200 arginine, (200 + 200) mixed mg liter (PPM) and the third factor is the use of two water stresses for water which is irrigation when draining (50-75)% of available water. The inoculation with mycorrhizae was significantly excelled by giving higher yields in grain yield 3.83 tons.ha-1, biological yield 11.30 tons.ha-1, the weight of 1000 grains (g) 96.08 g, proline 5.07 μmol g-1, 2-Spraying with amino acids at treatment A3 gave the highest values for all studied traits. The water stress treatment, which was designated W1, considerably outperformed its competitors by producing the highest values for growth markers from.

Effect of Potassium Silicate Spray and Water Stress on Yield and Yield Components of Sorghum

A field experiment was carried out for the year 2021-2022 at Al Buaitha Research Station of the College of Agriculture - Anbar University, to study the effect of potassium silicate and water stress on the growth and yield of sorghum. The experiment was carried out using a Split-Plot arrangement according to the Randomized Complete Block Design (RCBD) with three replications. The main plots included irrigation intervals (I1, irrigated every 4 days; I2, irrigated every 8 days; and I3, irrigated every 12 days), while the concentrations of potassium silicate fertilizer (250 S1, 500 S2, and 750 S3 ml liter−1 of distilled water), in addition to the control treatment S0, which was sprayed with distilled water only, allocated to the sub-plots. The results showed a significant effect of water stress treatments I1 and I2 on the average traits of head length, number of seeds per head, grain yield, and biological yield (26.20, 1920, 6.34, and 15.30 respectively). while, the treatments of potassium silicate fertilization S2 and S3 had a significant effect on the head length, number of seeds per head, grain yield, and biological yield (26.56, 1968, 6.12, and 14.63 respectively). The results also showed a significant interaction effect between the two study factors of I2S2, I1S2, I2S0, and I1S0 on the same traits (27.17, 2052, 6.52, and 16.32 respectively).

Short-range sensing for fruit tree water stress detection and monitoring in orchards: a review

Short-range sensing for fruit tree water stress detection and monitoring in orchards: a review

Co-inoculation of mycorrhizal fungi and plant growth-promoting rhizobacteria improve growth, biochemical and physiological attributes in Dracocephalum kotschyi Boiss. under water deficit stress.

Because of swift climate change, drought is a primary environmental factor that substantially diminishes plant productivity. Furthermore, the increased use of chemical fertilizers has given rise to numerous environmental problems and health risks. Presently, there is a transition towards biofertilizers to enhance crops' yield, encompassing medicinal and aromatic varieties. This study aimed to explore the impacts of plant growth-promoting rhizobacteria (PGPR), both independently and in conjunction with arbuscular mycorrhizal fungi (AMF), on various morphological, physiological, and phytochemical characteristics of Dracocephalum kotschyi Boiss. This experimentation took place under different irrigation conditions. The irrigation schemes encompassed well watering (WW), mild water stress (MWS), and severe water stress (SWS). The study evaluated the effects of various biofertilizers, including AMF, PGPR, and the combined application of both AMF and PGPR (AMF + PGPR), compared to a control group where no biofertilizers were applied. The findings of the study revealed that under water-stress conditions, the dry yield and relative water content of D. kotschyi Boiss. experienced a decline. However, the application of AMF, PGPR, and AMF + PGPR led to an enhancement in dry yield and relative water content compared to the control group. Among the treatments, the co-application of AMF and PGPR in plants subjected to well watering (WW) exhibited the tallest growth (65 cm), the highest leaf count (187), and the most elevated chlorophyll a (0.59 mg g-1 fw) and b (0.24 mg g-1 fw) content. Regarding essential oil production, the maximum content (1.29%) and yield (0.13 g plant -1) were obtained from mild water stress (MWS) treatment. The co-application of AMF and PGPR resulted in the highest essential oil content and yield (1.31% and 0.15 g plant-1, respectively). The analysis of D. kotschyi Boiss. essential oil identified twenty-six compounds, with major constituents including geranyl acetate (11.4-18.88%), alpha-pinene (9.33-15.08%), Bis (2-Ethylhexyl) phthalate (8.43-12.8%), neral (6.80-9.32%), geranial (9.23-11.91%), and limonene (5.56-9.12%). Notably, the highest content of geranyl acetate, geranial, limonene, and alpha-pinene was observed in plants subjected to MWS treatment following AMF + PGPR application. Furthermore, the co-application of AMF, PGPR, and severe water stress (SWS) notably increased the total soluble sugar (TSS) and proline content. In conclusion, the results indicate that the combined application of AMF and PGPR can effectively enhance the quantity and quality of essential oil in D. kotschyi Boiss., particularly when the plants are exposed to water deficit stress conditions.

Impact of water stress during reproductive development on seed dormancy in Bromus diandrus Roth and Lolium rigidum Gaudin

Context Bromus diandrus Roth and Lolium rigidum Gaudin are important weeds of cereal-based cropping systems of Australian agriculture. Adaptation to environmental stresses, protracted seed germination and herbicide resistance have made these weeds serious threats to crop production. Aims Studies were undertaken to determine the impact of moisture stress during reproductive development on the extent of seed dormancy and the expression of genes involved with gibberellic acid and abscisic acid synthesis. Methodology A pot study was undertaken at two locations, with two populations each of B. diandrus and L. rigidum. Water stress was applied from either the GS31 or GS60 stage until seed maturation, along with a well-watered treatment. Seeds of stressed vs well-watered treatments were assessed for seed dormancy and the expression of ABA1 and GA20ox genes using quantitative polymerase chain reaction. Results The seeds from GS31 treatment, where plants experienced the longest water stress, were most dormant in both weed species. Water stress treatments altered the expression of the GA20ox gene, which was correlated with the level of dormancy in seeds of B. diandrus and L. rigidum. Conclusions This investigation has provided clear evidence of the impact of water stress on seed dormancy and on expression of genes involved in regulating seed dormancy in these weed species. Implications As spring rainfall in the Australian agricultural landscape is highly variable, weeds are likely to experience variable levels of water stress during reproductive development, which in turn is likely to influence seed dormancy, weed seedling emergence and effectiveness of pre-sowing weed management next season.

Identification and fine mapping of qSW2 for leaf slow wilting in soybean

Drought is one of the abiotic stresses limiting the production of soybean (Glycine max). Elucidation of the genetic and molecular basis of the slow-wilting (SW) trait of this crop offers the prospect of its genetic improvement. A panel of 188 accessions and a set of recombinant inbred lines produced from a cross between cultivars Liaodou 14 and Liaodou 21 were used to identify quantitative-trait loci (QTL) associated with SW. Plants were genotyped by Specific-locus amplified fragment sequencing and seedling leaf wilting was assessed under three water-stress treatments. A genome-wide association study identified 26 SW-associated single-nucleotide polymorphisms (SNPs), including three located in a 248-kb linkage-disequilibrium (LD) block on chromosome 2. Linkage mapping revealed a major-effect QTL, qSW2, associated with all three treatments and adjacent to the LD block. Fine mapping in a BC2F3 population derived from a backcross between Liaodou 21 and R26 confined qSW2 to a 60-kb interval. Gene expression and sequence variation analysis identified the gene Glyma.02 g218100, encoding an auxin transcription factor, as a candidate gene for qSW2. Our results will contribute significantly to improving drought-resistant soybean cultivars by providing genetic information and resources.

Searching for a deficit irrigation strategy to save water and improve fruit quality without compromising pomegranate production

Deficit irrigation (DI) strategies have frequently studied in drought resistant crops to optimise water-use-efficiency and save water. Four different DI strategies were studied in fifteen-year-old pomegranate trees (Punica granatum (L.) cv. Mollar de Elche) during the season of 2021: irrigation at 120 % of ETc during the whole season (control, C); irrigation at 50 % of ETc during the whole season (SDI); irrigation at 50 % of ETc during the linear fruit growth phase (RDIfg) and irrigation at 25 % of ETc during the ripening phase (RDIr). The effects of DI treatments on water relations, gas exchange, canopy temperature, yield and fruit quality were analysed. Water status of pomegranate responded closely to changes in soil water content. The reduction of leaf osmotic potential and leaf osmotic potential at full turgor to SDI, RDIfg and RDIr treatments indicated an osmotic adjustment. The stem water potential and the crop water stress index were more sensitive to water stress than gas exchange. SDI treatment increased non-marketable fruit weight and number. Nevertheless, RDIfg treatment could be considered a non-critical period because of the low sensitivity to water stress of trees, yield maintenance and the increase of nutritional organic compounds in fruits, saving 27 % of irrigation water. The application of RDIr produced the highest content of bioactive compounds, saving 8 % of water saving with a slight increase of non-marketable fruit number and weight. This suggests that the intensity and duration in which the deficit irrigation was applied could set the threshold irrigation conditions above which pomegranate production could be negatively affected.

Magnesium supplementation alleviates drought damage during vegetative stage of soybean plants.

Our working hypothesis was that magnesium (Mg) supplementation modulates plant performance under low water availability and improves drought tolerance in soybean genotypes. Plants of Bônus 8579, M8808 and TMG1180 genotypes were grown under field conditions and subjected to three water stress treatments (control, moderate and severe stress) and three Mg levels [0.9 (low), 1.3 (adequate) and 1.7 cmolc dm-³ (supplementation)]. After 28 days of drought imposition, the growth parameters, osmotic potential, relative water content, leaf succulence, Mg content and photosynthetic pigments were assessed. In general, drought drastically decreased the growth in all genotypes, and the reductions were intensified from moderate to severe stress. Under adequate Mg supply, TMG1180 was the most drought-tolerant genotype among the soybean plants, but Mg supplementation did not improve its tolerance. Conversely, although the M8808 genotype displayed inexpressive responses to drought under adequate Mg, the Mg-supplemented plants were found to have surprisingly better growth performance under stress compared to Bônus 8579 and TMG1180, irrespective of drought regime. The improved growth of high Mg-treated M8808-stressed plants correlated with low osmotic potential and increased relative water content, as well as shoot Mg accumulation, resulting in increased photosynthetic pigments and culminating in the highest drought tolerance. The results clearly indicate that Mg supplementation is a potential tool for alleviating water stress in M8808 soybean plants. Our findings suggest that the enhanced Mg-induced plant acclimation resulted from increased water content in plant tissues and strategic regulation of Mg content and photosynthetic pigments.

ROLE OF NANO AND METALLIC BORON FOLIAR NUTRITION ON WATER STRESS REDUCING IN SWEET CORN YIELD AND ITS COMPONENTS

A field experiment was conducted in the experimental field of the Crop Sciences Department at the College of Agricultural Engineering Sciences - University of Baghdad during fall seasons of 2021 and 2022. The aim of this study was to investigate the role of nano and metallic boron foliar nutrition on yield, components, water use efficiency, and water consumption under water stress for sweet corn (Zea mays L.). Randomized Complete Block Design was used within split -plot arrangement with three replicates, where the main plots included three levels of water stress (irrigation at 40, 60, and 80% of available water) coded as W1, W2, and W3, respectively. The nano and metallic boron spray concentrations represented 5, 10, 20, and 40 mg L-1 coded as N1, N2, M1, and M2, respectively. Results showed that nano and metallic boron concentrations significantly affected all the studied traits. The concentration of 5 mg L-1 of nano boron N1 significantly exceeded other concentrations under study in increasing ear length, number of rows per ear, number of grains per row, and weight of 500 grains, which positively reflected on improving grain yield of 5.93 and 5.96 t ha-1. The interaction between water stress treatments and nano and metallic boron concentrations was significant for all the studied traits except for ear length.

Determination of Yield and Quality Parameters in Pickling Hot Peppers Grown under Different Water Stress Conditions

Plants are exposed to various adverse environmental conditions throughout their growth period. In recent years, drought, which has occurred and necessitated different measures, ranks among these adverse conditions. At the same time, plants synthesize certain biochemical compounds in response to the adverse conditions they will encounter. These compounds not only strengthen the immune system but also provide resistance against various diseases, and they tend to increase under adverse environmental conditions that plants will face during cultivation. This study was conducted to determine the changes in yield and some biochemical components in pickling hot peppers (Capsicum Annuum L.) grown under different water stress conditions. Two different levels of water stress (%70 and %30 irrigation) were applied in addition to full irrigation (%100 irrigation). At the end of the research, while a yield of 269.42 g per plant was obtained in the control group (%100 irrigation), 150.14 g and 93.33 g of pickling hot peppers were harvested in each water stress treatment, respectively. Total phenolic compound levels increased with water stress; it was determined to be 0.827 mg-1g in the trial irrigated with full irrigation water, 1.170 mg-1g in plants exposed to mild water stress, and up to 1.536 mg-1g in the trial subjected to severe water stress. In addition, total flavonoids and antioxidant compound levels also increased with increasing water stress. The amounts of flavonoid compounds obtained from the trial groups were 0.146, 0.373, and 0.412 mg-1g, respectively, while the antioxidant levels determined by the DPPH method increased in quantity with increasing water stress, similar to other biochemical compounds. According to these results, it was determined that the yield of pickling hot peppers decreased in the case of water shortage that the plants would face in cultivation, but there was an increase in some biochemical compounds.