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A four-year research experiment was conducted on sandy loam soil at the University of California Kearney Agricultural Research and Extension Center in Parlier, California, to investigate the effect of midsummer deficit irrigation on alfalfa yield, irrigation water productivity (IWP), and crop water productivity (CWP). The experiment was a randomized block design with two treatments: full and deficit irrigations with three replications. Applied irrigation water was measured using flow meters and soil matric potentials were monitored using watermark soil moisture sensors. Actual evapotranspiration (ETa) values were estimated from Tule Technologies stations. The deficit irrigation treatments resulted in 454, 706, 625, and 815 mm of irrigation water savings as compared to the full irrigation treatments in 2019, 2020, 2021, and 2022, respectively. These values represent 30.3%, 40.9%, 37.0%, and 49.1% of the applied water savings. Alfalfa yield in the deficit treatments was reduced by 3.94, 2.04, 1.25, and 0.40 Mg ha−1 ; the equivalent of 18.1%, 11.1%, 7.1%, and 3.0% of the yield for the full irrigation treatment for the four years: with an average reduction of 10.7%. IWP was higher when deficit irrigation was implemented and resulted in 17.09, 16.11, 15.40, and 15.54 kg ha−1 mm−1 , in 2019, 2020, 2021, and 2022, respectively. The production function using applied irrigation water (IW, mm) was: Y(yield in Mg ha−1)=0.50×(IW)2−1,633.75×(IW)+1,338,472 and Y=−0.1137×(IW)2+233.55×(IW)−103,036 for the full and deficit irrigation treatments, respectively. CWP was 18.6, 16.4, 14.9, and 12.3 kg ha−1 mm−1 for fully irrigated treatments, and 15.2, 14.9, 14.3, and 12.6 kg ha−1 mm−1 for the deficit irrigation treatments, for 2019, 2020, 2021, and 2022, respectively. Results from this work provide growers with viable deficit irrigation practices that could be implemented during drought periods. [ABSTRACT FROM AUTHOR]

Triticale is a man-made crop produced by crossing wheat (Triticum aestivum) and rye (Secal cereal) with the aim of increasing the adaptability and potential production of its parental line (wheat) under environmental stresses and harsh conditions. Accordingly, the objectives of this study are as follow, a: compare different stability measurement methods regarding their suitability, b: identify most stable genotypes for cultivar release, and c: provide a freely available package in R programming language (named 'Stbidx') capable of exploiting all stability methods for similar studies. Accordingly, 30 triticale genotypes were evaluated for their stability and adaptability to changing environments during four consecutive years from 2016 to 2020 in different locations in Iran (one year in Zarghan, two years in Ghorveh, one year in Sanandaj) and under two different irrigation regimes (normal irrigation and water deficit stress conditions). All 30 triticale genotypes were cultivated in a randomized complete block design (RCBD) with three replications in each environment (12 environments: 6 trials in 2 conditions). Grain yield of triticale genotypes was measured and it applied to calculate all known stability indices (univariate methods) along with the meta-analysis models were evaluated in this study. Additionally, two novel techniques (Stability ID: SID and AMMI PC Value: APCV) were introduced and successfully tested for screening stable genotypes. These methods were introduced to improve and resolve the limitation of the previous stability methods. Meanwhile, heatmap analysis, as a proper data-mining technique, has been successfully applied for the first time to find stable genotypes in different environments in this study. The results clearly indicated a higher suitability of our introduced methods over previous multi-trials screening methods. Based on our methods and considering all environments, triticale genotypes ELTTCL21 (SID = 8.00; APCV = 28.12), ELTTCL25‌ (SID = 8.14; APCV = 30.02), ELTTCL30 (SID = 8.43; APCV = 17.00), ET-90-8 (SID = 14.00; APCV = 42.05), and Sanabad (SID = 10.57; APCV = 12.44) were among stable genotypes and they can be nominated as new cultivars. Additionally, for stress condition genotypes ELTTCL30 (stress: 380.6 g/m2) and ELTTCL18 (stress: 360.79 g/m2) and for normal condition genotypes ET-90-4 (normal: 849.4 g/m2) and ELTTCL20 (normal:845 g/m2) were respectively the most proper genotypes with the highest production to be considered for each condition separately. [ABSTRACT FROM AUTHOR]

Water scarcity is a major environmental stress that negatively affects the soil traits, growth of plants, and yield of crops. This research assessed the impact of vermicompost, oak tree biochar, apple tree biochar, and the combined impact of vermicompost and both biochars on the growth, water use efficiency (WUE), and yield of eggplant under conditions of limited irrigation. The main purpose of the study was deficit irrigation, which involved 3 levels of water supply: 50%, 75%, and 100% PWR (plant water requirement). The second focus was on the application of vermicompost, with two levels: 0 and 2000 gm−2, as well as biochar, with two levels: 0, 400 gm−2 of oak-tree biochar, and 400 gm−2 of apple tree biochar. The findings revealed that the combination of apple-tree biochar and vermicompost at a level of 100% PWR, delivered the most positive results in terms of plant growth and functioning. The early harvest yield was greatest when apple-tree biochar was applied alone at a level of 50% PWR. However, the total yield of the plant was highest when apple-tree biochar and vermicompost combined were applied at a level of 100% PWR. The plant's WUE reached its highest level after the combined application of apple-tree biochar and vermicompost at a level of 50% PWR. The maximum leaf levels of N, P, K, Fe, and Mg were observed when both vermicompost and apple-tree biochar were applied at a level of 100% PWR. The treatments without amendments or with vermicompost only at a level of 50% PWR exhibited the highest values of physiologically significant stress metabolites. [ABSTRACT FROM AUTHOR]

The objective of the present review article was to update the standard single (Kc) and basal (Kcb) crop coefficients published in the FAO Irrigation and Drainage Paper No. 56 (FAO56), focusing on temperate climate fruit trees (pome, stone and nut fruit trees), vines and shrubs (kiwi, hop and blue- and blackberries). Standard conditions refer to crops grown in medium to large fields, having enough fetch for non-impeding accurate use of flux measuring equipment to represent non-limiting conditions of crop evapotranspiration, ETc. Moreover, the crop needs to be managed without soil water deficit, free of pests and diseases, and must be able to reach full production under the given environmental conditions. For this purpose, more than 150 articles published over the last 25 years were reviewed. Of these, we selected 76 that refer to case studies that reporting on appropriate yield conditions, describe adequate ETc measurement and adopt the FAO reference evapotranspiration or another method closely related to it. The selection of papers to be analysed followed the same methods as the companion papers on Mediterranean woody fruit crops (Pereira et al. 2023), and on tropical and subtropical ones (Paredes et al. 2024). The literature review focused on articles that are in line with the FAO56 methodology; that is, where the grass reference evapotranspiration (ETo) was computed with the FAO Penman–Monteith ETo, the ASCE Penman–Monteith ETo equations, or other equations whose results relate well to the former. In addition, where the crop evapotranspiration (ETc) and/or crop transpiration (Tc) were determined with sufficient accuracy from field observations in crops grown under standard, well-watered conditions, i.e., under pristine (i.e., non-stress cropping conditions) or eustress (i.e., "good stress") conditions. Information collected from the selected studies included cultivar and rootstock, plant density and spacing, training system, fraction of ground cover or intercepted PAR radiation, crop height and age. Additional data were gathered on irrigation system and strategy for full or deficit irrigation. The Kc and Kcb values reported were recomputed and grouped according to the degree of ground cover, training system and plant density. Thus, the proposed tabulated standard Kc and Kcb values for initial, mid- and end-season are based on the values obtained from field observations reported in the selected papers, and on the ranges of Kc/Kcb values previously tabulated, mainly in FAO56. The currently tabulated values are updated, with the aim being their use in orchard management. They should consist of the upper limit of Kc/Kcb application, and take into account the general awareness of water scarcity and water conservation, thus helping improve the accuracy in estimating crop water requirements and optimizing irrigation scheduling. [ABSTRACT FROM AUTHOR]

Efficient and affordable plant phenotyping methods are an essential response to global climatic pressures. This study demonstrates the continued potential of consumer-grade photography to capture plant phenotypic traits in turfgrass and derive new calculations. Yet the effects of image corrections on individual calculations are often unreported. Turfgrass lysimeters were photographed over 8 weeks using a custom lightbox and consumer-grade camera. Subsequent imagery was analyzed for area of cover, color metrics, and sensitivity to image corrections. Findings were compared to active spectral reflectance data and previously reported measurements of visual quality, productivity, and water use. Results confirm that Red–Green–Blue imagery effectively measures plant treatment effects. Notable correlations were observed for corrected imagery, including between yellow fractional area with human visual quality ratings (r = −0.89), dark green color index with clipping productivity (r = 0.61), and an index combination term with water use (r = −0.60). The calculation of green fractional area correlated with Normalized Difference Vegetation Index (r = 0.91), and its RED reflectance spectra (r = −0.87). A new chromatic ratio correlated with Normalized Difference Red-Edge index (r = 0.90) and its Red-Edge reflectance spectra (r = −0.74), while a new calculation correlated strongest to Near-Infrared (r = 0.90). Additionally, the combined index term significantly differentiated between the treatment effects of date, mowing height, deficit irrigation, and their interactions (p < 0.001). Sensitivity and statistical analyses of typical image file formats and corrections that included JPEG, TIFF, geometric lens distortion correction, and color correction were conducted. Findings highlight the need for more standardization in image corrections and to determine the biological relevance of the new image data calculations. [ABSTRACT FROM AUTHOR]

In the context of global warming, rising air temperatures are increasing evapotranspiration ( ET c ) in all agricultural crops, including rice, a staple food worldwide. Simultaneously, the occurrence of droughts is reducing water availability, affecting traditional irrigation methods for rice cultivation (flood irrigation). The objective of this study was to determine ET c (water use) and yield performance in rice crop under different irrigation regimes: treatments with continuous flood irrigation (CF) and irrigations with alternating wetting and drying ( A W D 5 , A W D 10 , and A W D 20 ) in an experimental area in INIA–Vista Florida. Water balance, rice physiological data, and yield were measured in the field, and local weather data and thermal and multispectral images were collected with a meteorological station and a UAV (a total of 13 flights). ET c values obtained by applying the METRICTM (Mapping Evapotranspiration at High Resolution using Internalized Calibration) energy balance model ranged from 2.4 to 8.9 mm d−1 for the AWD and CF irrigation regimes. In addition, ET c was estimated by a water balance using the AquaCrop model, previously parameterized with RGB image data and field weather data, soil, irrigation water, and crops, obtaining values between 4.3 and 7.1 mm d−1 for the AWD and CF irrigation regimes. The results indicated that AWD irrigation allows for water savings of 27 to 28%, although it entails a yield reduction of from 2 to 15%, which translates into an increase in water use efficiency (WUE) of from 18 to 36%, allowing for optimizing water use and improving irrigation management. [ABSTRACT FROM AUTHOR]

Climate change-caused water deficiency is a major threat to crop production. Different strategies such as biochar and mycorrhiza are suggested as a solution to improve water storage in the soil and increase plant tolerance to moisture deficiency. This study tested the hypothesis that under deficit irrigation conditions, the combined application of biochar and mycorrhiza can increase maize photosynthesis activity, growth, and water use efficiency (WUE). A greenhouse experiment was established to understand the effect of biochar and mycorrhizal inoculation with deficit irrigation on maize (Zea mays L.) growth, photosynthesis activity, and WUE. A factorial randomized pot experiment was designed using three biochars (B) doses from three different feedstock (DF) and three mycorrhizae (M) species (without mycorrhizae, Rhizophagus clarus and indigenous mycorrhiza), with three different irrigation (I) levels, namely, I100, I75, and I50 respectively 100%, 75%, and 50% of field capacity. For each biochar application, of 0%, 1%, and 2% rates of soil weight were applied. Maize plant dry matter (DM), photosynthesis activities, and leaf water use efficiency (WUEL) were measured. The results showed that deficit irrigation levels, such as I75 and I50 can be used for maize plant growth. Mycorrhizal inoculation increased maize plant growth between 8.2% and 8.9%, whereas biochar increased growth. In addition, mycorrhizal inoculation increased the photosynthesis activity by 9.3%. All the biochars increased maize growth and photosynthesis activity compared to the control, however, poultry manure biochar had the highest growth, photosynthesis activity, and WUE. In addition, statistically, there were no significant differences between B0*M0*I100 and B*M*I50 applications in terms of photosynthesis activity, WUE, and DM. Combined application of biochar and mycorrhiza statistically reduced irrigation water use by 50% without affecting plant DM production. [ABSTRACT FROM AUTHOR]

The objective this study was to evaluate the effects of foliar application of ascorbic acid – AsA on the production and postharvest quality of sour passion fruit under deficit irrigation strategies. The experimental design was randomised blocks, in a split-plot scheme, with plots consisting of six strategies of irrigation with water deficit, based on crop evapotranspiration – ETc (irrigation with 100% ETc during the entire cycle – S1; irrigation with 50% ETc in the different stages: vegetative – S2; flowering – S3; fruiting – S4; and successively in the vegetative/flowering stages – S5; and vegetative/fruiting stages – S6) and three concentrations of AsA (0, 88.06 and 176.12 mg/L), with three replicates and three plants per plot. Water deficit reduces the production of sour passion fruit, regardless of the phenological stage of the plants without AsA application. Irrigation with water deficit in the flowering stage (50% of crop evapotranspiration) reduces the physical and chemical quality of sour passion fruits. Ascorbic acid in applied levels was effective in alleviating the effects of water deficit on production, with emphasis on the concentration of 176.12 mg/L on the quality of sour passion fruits, in the period from 160 to 220 days after transplanting. [ABSTRACT FROM AUTHOR]

AbstractWater deficit is the most common abiotic stress and at least 75% of corn fields in Iran are exposed to drought stress during different stages of growth. humic acid (HA) and nanosilver (NS) can help mitigate abiotic stresses in plants; especially drought stress. A field experiment was conducted to study the effect of humic acid and nanosilver on the physiological traits and yield of corn during two crop years. Experimental treatments were including deficit irrigation (100%, 80%, 60% of crop water requirement (CWR)) and nanosilver (0 (NS0), 60 (NS60), 80 (NS80) and 100 (NS100) microliters/liter/ha) and humic acid (control (HA0), 500 (HA500) and 1000 (HA1000) g/ha). The highest amount of chlorophyll a, b and total in 100% CWR+NS60+HA1000 was obtained. The highest amount of proline in 60% CWR + NS60 +HA1000 as well as treatment NS0 +HA1000 were observed. In all irrigation levels, the application of NS100 has reduced chlorophyll a and total. The yield components were affected by HA and nanosilver foliar spraying. The highest grain yield was observed in 100% CWR with the application of NS60 +HA500 at the rate of 10,582 kg/ha. In conditions of 100% CWR, nanosilver concentrations had a positive effect on plant growth and yield, and with increasing stress, high concentrations of nanosilver had a negative effect on growth and yield, but with the combined application of nanosilver and HA, the effect of drought stress decreased, which indicates the positive effect of HA in improving plant growth and yield. [ABSTRACT FROM AUTHOR]

Super high-density (SHD) planting systems are very efficient in terms of production and water use. In these orchards, water-saving irrigation strategies are used precisely to keep the best sustainability compared to traditional orchards. With agro-climatic and eco-physiological parameter monitoring, the SHD planting system has become even more efficient. SHD orchards, however, could also be more so affected by other pests and diseases than traditional systems, but field responses are still unknown when olive trees are grown in SHD groves. The goal of this two-year field research was to investigate the seasonal changes of the phytosanitary status of 'Arbosana' grown in an SHD orchard under both regulated deficit (RDI) and full irrigation regimes (FI). This study investigated the influence of the two different irrigation regimes on the infections of three olive tree key diseases: cercosporiosis (Pseudocercospora cladosporioides), cycloconium (Fusicladium oleagineum), and olive knot (Pseudomonas savastanoi pv. savastanoi). RDI significantly reduced the severity of cercosporiosis in 2020 compared to FI but not in 2021. Cycloconium was observed only as a latent infection during the two studied years and olive knot was not influenced by irrigation but only by weather conditions. These findings suggest that irrigation management can play a key role in controlling cercosporiosis effectively in SHD olive orchards, but also that weather conditions have an even higher impact on the tree key diseases. [ABSTRACT FROM AUTHOR]

This work was conducted over three-year monitoring seasons of three almond cultivars (Guara, Marta, and Lauranne) subjected to deficit irrigation in combination with cover crops in a Mediterranean semiarid area (SW, Spain). Four water–soil treatments were evaluated based on the conjunction of two irrigation strategies: fully irrigated (FI), covering 100% of the ETC, and regulated deficit irrigation (RDI), with two soil-management systems: bare soil (BS) and cover crop based on a mixture of vetch (Vicia sativa L.) and oat (Avena sativa L.) (CC). Throughout the study period in trees, the yield, the stem water potential (Ψstem), leaf nutrient content (N, P, K, Ca, Mg, Na, Fe, Zn, Mn, and Cu) in soils, organic carbon, microbial biomass, fluoresceine diacetate, and enzymatic activities (dehydrogenase, protease, β-glucosidase, and alkaline phosphatase) were determined. In addition, the dry matter and carbon fixation by plant covers were evaluated. For Guara and Lauranne, yield reductions (22 and 26%, respectively) were found for water-stressed (RDI-CC) plots with respect to non-stressed combination (FI-CC) plots, contrasting with cv. Marta, without a significant impact on productivity in all combinations. That is, the RDI (~3.000 m3 ha−1) strategy enabled acceptable productivity, offering promising possibilities for cultivation performance under water-scarcity scenarios. Important differences in Ψstem could be observed and ascribed to irrigation strategies, especially for Guara and Lauranne, but without significant effects due to the soil-management systems applied. No differences were observed in the tree nutritional status due to the presence or absence of CC; however, its presence increased the fixation of atmospheric carbon, which was not the case under BS conditions. Additionally, CC significantly fostered the microbial processes and enzymatic activities, particularly in upper soil layers (0–10 cm) and with plenty of water supply in FI-CC plots and to a lesser extent in RDI-CC plots, which could encourage prominent aspects for soil quality and health restoration. Thus, the cover crop is congruent with RDI to facilitate soil functionality and water savings in a changing climate, contributing to resilient farming systems in the Mediterranean environment. [ABSTRACT FROM AUTHOR]

Context: Preharvest granulation of Imperial mandarins is a significant problem for the Australian market. Causes of, and solutions for, this physiological disorder are poorly understood despite decades of research worldwide. Aims: This research aimed to find management practices for growers to reduce granulation. Methods: A 5-year on-farm trial in central Queensland, Australia, compared standard versus deficit irrigation and five rates of winter nitrogen application. Key results: Reducing water (irrigation plus rainfall) in the 16–18 weeks following flowering reduced granulation in 3 of 5 years. Granulation increases with ratio of total water received to evapotranspiration, particularly in low crop load years. Higher nitrogen applications reduced granulation in 4 of 5 years, although treatment means were only significantly different at α = 0.05 in 1 year. Granulation increased with stronger early spring flush growth in a low crop load year and with later spring flush growth in one of two high crop load years. The deficit irrigation treatment had less spring flush growth and higher fruit set than the control in all years. Higher nitrogen treatments had more flush growth in high crop load years and less in low crop load years. Our data suggests competition between flush growth and fruit development for mineral resources and/or carbohydrates is a factor in the variability of granulation from fruit to fruit, but crop load is more important. Conclusions: The three key strategies to minimise granulation are to maintain high crop loads, reduce irrigation after flowering, and apply sufficient nitrogen in winter. Implications: This research will improve fruit quality for the consumer and financial returns to growers. Granulation, a physiological disorder in which citrus fruit are white, dry and tasteless, is a significant problem for Imperial mandarins in Australia. We discovered that excessive irrigation and insufficient nitrogen fertilisation are important causes of granulation and three key strategies to minimise granulation are to maintain high crop loads, reduce irrigation after flowering, and apply sufficient nitrogen in winter. This research will improve fruit quality for the consumer and financial returns to growers. [ABSTRACT FROM AUTHOR]

Remote sensing is now a valued solution for more accurately budgeting water supply by identifying spectral and spatial information. A study was put in place in a Vitis vinifera L. cv. Cabernet-Sauvignon vineyard in the San Joaquin Valley, CA, USA, where a variable rate automated irrigation system was installed to irrigate vines with twelve different water regimes in four randomized replicates, totaling 48 experimental zones. The purpose of this experimental design was to create variability in grapevine water status, in order to produce a robust dataset for modeling purposes. Throughout the growing season, spectral data within these zones was gathered using a Near InfraRed (NIR) - Short Wavelength Infrared (SWIR) hyperspectral camera (900 to 1700 nm) mounted on an Unmanned Aircraft Vehicle (UAV). Given the high water-absorption in this spectral domain, this sensor was deployed to assess grapevine stem water potential, Ψstem, a standard reference for water status assessment in plants, from pure grapevine pixels in hyperspectral images. The Ψstem was acquired simultaneously in the field from bunch closure to harvest and modeled via machine-learning methods using the remotely sensed NIR-SWIR data as predictors in regression and classification modes (classes consisted of physiologically different water stress levels). Hyperspectral images were converted to bottom of atmosphere reflectance using standard panels on the ground and through the Quick Atmospheric Correction Method (QUAC) and the results were compared. The best models used data obtained with standard panels on the ground and allowed predicting Ψstem values with an R2 of 0.54 and an RMSE of 0.11 MPa as estimated in cross-validation, and the best classification reached an accuracy of 74%. This project aims to develop new methods for precisely monitoring and managing irrigation in vineyards while providing useful information about plant physiology response to deficit irrigation. [ABSTRACT FROM AUTHOR]

Maize is widely growth in arid and semi-arid region where, drought is common and a limiting factor for crop production. Potassium plays a key role in enhancing plant growth under drought condition. The objective of this study is to determine the effect of K fertilization with and without NP on maize growth grown in sandy loam soil under adequate and deficit irrigation conditions. The following treatments were investigated in pot experiment: (1) control with no fertilizer application (C); (2) 128 kg N + 328 kg P2O5 ha-1 (NPK0); (3) 128 kg N + 328 kg P2O5 ha-1 + 152.5 kg K2O ha1 (NPK1); (4) 128 kg N + 328 kg P2O5 ha-1 + 305 kg K2O ha-1 (NPK2); and 128 kg N + 328 kg P2O5 ha-1 + 457.5 kg K2O ha-1 (NPK3). Treatments were investigated under adequate and deficit soil moisture content. Each pot filled with 3.5 kg air-dry soil and seeded with maize and pots were watered according to the treatments. The results indicated that plant growth and nutrient uptake were significantly reduced under water stress condition. The application of NP increased plant growth and nutrient uptake and further were increased with K application. K application also enhanced plant tolerance to deficit soil moisture condition. In addition, K enhanced nutrient uptake and leaf chlorophyll content. Based on the results, it can be concluded that application of NP for maize was not adequate to achieve the highest plant growth, unless it is combined with K application. In addition, K application enhances plant tolerance to water stress. [ABSTRACT FROM AUTHOR]

The increase in crop yield can be primarily attributed to the combined effect of genetic advancements, as well as increased contributions from nitrogen (N) and water. The accumulation of dry matter plays a crucial role in determining grain yield in winter wheat. The current study aimed to better understand the source‐sink dynamics, analyse the dry matter transport (DMT) before and after anthesis and calculate its ratio to grain yield. In this experiment, eight main cultivars of winter wheat that have been widely cultivated in Shaanxi Province since the 1940s were selected as planting material. Field examinations were conducted using three levels of both irrigation and N. The yield‐related parameters, dry matter accumulation, dry matter distribution, DMT and DMT efficiency were measured. The results showed that irrigation prolonged the time of dry matter accumulation, and the application of N fertiliser increased the rate of dry matter accumulation. The analysis of the dynamic characteristic parameters of dry matter in winter wheat showed that irrigation and N had a significant impact on rate of dry matter accumulation. The proportion of stems, leaves and spikes of new varieties increased significantly (p < 0.05), which increased by 56.67%–69.7%, 13.26%–18.07% and 15.78%–28.26%, respectively, with the varietal improvement. The DMT efficiency increased with varietal improvement and also with increased irrigation and N application. The response of irrigation treatment to DMT and dry matter was more significant. In addition, the irrigation treatment had a higher effect on the DMT efficiency of vegetative organs after anthesis. The logistic equation analysis revealed that water stress accelerated the fulfilment of maximum daily temperature (Tmax), while both the maximum growth rate (Gmax) and dry matter weight (Wmax) decreased as water stress increased. There was a positive linear relationship between dry matter accumulation after anthesis and grain yield. The structural equation model showed that varieties, N application and irrigation had significant positive effects on DMT, post‐anthesis dry matter and grain yield, while irrigation had significant negative effects on DMT efficiency. The accumulation of dry matter in winter wheat after anthesis showed a significant increase with the succession of varieties. The combination of moderate deficit irrigation and fertilisation improved transportation and dry matter accumulation after anthesis in winter wheat, thereby enhancing its production capacity. [ABSTRACT FROM AUTHOR]

Soybeans are a crucial major food source in human and animal nutrition due to their high fat and protein content. This study investigated the effects of different irrigation methods on yield and yield components of second-crop soybeans under deficit irrigation conditions. The study aimed to determine the crop evapotranspiration, water productivity (WP), and irrigation water productivity (IWP) of the second crop soybean. The study followed a split plot random block experimental design with three replications. The main treatments of the study were subsurface drip irrigation (SDI), drip irrigation (DI), and furrow irrigation (FI) with four different water application levels (100%, 75%, 50%, and 25%) serving as subtreatments. Crop evapotranspiration (ETc) ranged between 236–482 mm for DI, 185–410 mm for SDI, and 275–562 mm for FI during 2018 and 2019. The yields for DI, SDI, and FI varied between 3,340–4,030 kg ha−1 , 3,250−3,780 kg ha−1 , and 2,800–3,680 kg ha−1 during 2018 and 2019, respectively. The effect of water deficit applications on yield was statistically significant at p<0.05 level. It was determined that the yield components of soybeans were negatively affected by deficit irrigation treatments, but the effect of different irrigation methods was not significant. There was no statistical difference between the treatment with 25% deficit irrigation and the full irrigation comparing the yield and yield components of the study. Moreover, WP and IWP values increased as the amount of irrigation water decreased in all irrigation methods. Thus, a 25% deficit is recommended as an alternative to full irrigation in the Mediterranean Basin when water resources are scarce. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the evaporation (E) and transpiration (T) components of evapotranspiration (ETc), and the growth parameters of curly lettuce (Lactuca sativa L. cv. Caipira) grown under different irrigation treatments. The study was conducted in a Mediterranean-type plastic greenhouse located in Antalya, Türkiye, in the fall and spring growing seasons of 2020 and 2021, respectively. To assess the impact of water stress on ETc and its components, three different irrigation water levels [ I100 for full irrigation treatment (100%), I66 for 66% (I100×0.66), and I33 for 33% (I100×0.33)] were selected. Planted and unplanted pots were used to measure ETc and E independently. The values obtained from these measurements were used as inputs to calculate the evaporation that occurred in the soil under the crop canopy and plant transpiration. In the present study, T was determined indirectly from the difference of measured evapotranspiration and evaporation and estimated with the modified Hernandez-Suarez model (Te). The modified model for the different irrigation treatments showed high Te estimation performance. Evaporation from the soil in the planted pots (Es) was calculated by considering the canopy cover and soil water content. The study revealed that water stress significantly affected lettuce plant height, root length, cover percentage, leaf area index (LAI), number of leaves, fresh and dry head weights, and root weights (p<0.01). The study also investigated the relationship between Es/ETc , and LAI using an exponential method and established a strong nonlinear relationship in all irrigation treatments (R2>0.90). The modified model developed for different irrigation treatments in Mediterranean-type greenhouses can be used to predict lettuce ETc values with greater precision and to better understand the partitioning of ETc into its constituent components. [ABSTRACT FROM AUTHOR]

The use of carbonaceous materials such as biochar has been considered an innovative solution in agriculture, especially to mitigate dry events caused by climate change. Biochar can improve water holding capacity, physical and chemical properties of soil, and increase the productivity of agricultural systems. However, underlying physiological mechanisms remain poorly understood. Mineral supplementation with potassium nitrate (KNO3) via foliar application is another promising strategy in agricultural management under irrigation deficit. Thus, we investigated the combined effects of biochar and foliar application of KNO3 on growth, yield, and physiology of tomato plants under different irrigation regimes. Results did not indicate a synergistic effect of biochar and foliar application of KNO3. Biochar application alleviated tomato plant stress under deficit irrigation, with plants showing better functioning of photosynthetic apparatus, higher yield, and better fruit quality, as well as increased water use efficiency. Coffee husk biochar (K-rich feedstock) fully met the tomato plant's demand for K and partially met the demand for some other elements (P, Mg, Fe, Zn, Mn, and Cu). Although positive effects of KNO3 application was verified for some physiological and fruit quality components, overall, foliar application of KNO3 did not improve tomato yield. It is concluded that biochar soil amendment can be a promising practice to increase yield and quality of tomato fruits under deficit irrigation. Therefore, biochar-based fertilizer can be an alternative K source that also provides stable carbon to soil and helps to mitigate stress caused by prolonged drought. [ABSTRACT FROM AUTHOR]

The present investigation assesses a variety of parameters available in the literature to model gold–water interfaces using molecular dynamics simulations. The study elucidates the challenges of characterizing the solid–liquid affinity of highly hydrophilic gold–water interfaces via wettability. As an alternative, the local pairwise interaction energy was used to describe the solid–liquid affinity of flat and curved surfaces, where for the latter, the calculation of a contact angle becomes virtually impossible. Regarding the heat transfer properties of different interface models (flat and curved), partly conclusive trends were observed between the total pairwise interaction energy and the thermal boundary conductance. It was observed that the solid surface structure, interfacial force field type, and force field parameters created a characteristic bias in the interfacial water molecules (liquid structuring). Consequently, a study of the liquid depletion layer provided better insight into the interfacial heat transfer among different interfaces. By computing the density depletion length, which describes the deficit or surplus of energy carries (water molecules) near the interface, a proper characterization of the thermal boundary conductance was obtained for the different gold–water interfaces. It was observed that the interfacial heat transfer is favored when the water molecules organize in cluster-like structures near the interface, by a surplus of water molecules at the interface, i.e., lower density depletion length, and by the closeness of water to the solid atoms. [ABSTRACT FROM AUTHOR]

Background: While water availability is important for quality at harvest, it also continues to influence the quality of pomegranates during storage. Reducing the amount of irrigation, in addition to water saving has different effects on bioactive compounds of pomegranate during storage time. This study was conducted to determine the influence of irrigation level on fruit quality changes during storage period of two commercial Iranian pomegranate cultivars ('Shishecap' and 'Malas-Yazdi'). Sustained deficit irrigation (SDI) was applied to plants that received 75% (moderate stress) or 50% (severe stress) of their normal water requirement. A control group received 100% of their water requirement. Results: At harvest time and during storage period, fruit weight loss and some biochemical traits such as fruit total soluble solids (TSS), titratable acidity (TA), pH, total phenolic compounds (TPC), total anthocyanins content (TAC), antioxidant activity and vitamin C were measured in pomegranate fruits. Also, the quantity of the produced product was also measured at the time of harvesting. Results indicated that control fruits exhibited more weight loss than those produced under water deficit during the storage period in both years. According to results, fruit TSS, TAC, and antioxidant activity significantly increased during storage period but fruit TA and vitamin C significantly decreased throughout storage period. Also, reduction in irrigation level resulted in a decline in the yield. Conclusions: This study revealed a crucial link between irrigation level and the quality of pomegranate fruits, despite a reduction in the yield. This included affecting weight loss and the content of bioactive compounds, both at harvest and during storage. [ABSTRACT FROM AUTHOR]

This study aims to develop an Artificial Neural Network (ANN) modeling to be trained to forecast the effects of different irrigation water levels and fertilizer doses on the hay yield and some quality traits of herbal parts of Sorghum × Sudan grass hybrid (Sorghum sudanense vs. Sorghum bicolor). The ANN model was developed on the limited field experiments implemented in Bilecik, Turkey, for 2 years in 2021 and 2022. Experiments were conducted in split-plot design with three replications. In the study, three irrigation levels (I100, I60, and I30) were placed in the main parcels, and four fertilizer levels (N0, N50, N100 and N150 kg ha−1) were placed in the sub-parcels. Irrigations were made in three critical periods according to the amount of cumulative evaporation occurring in the Class A Pan. The results showed that irrigation and fertilization are important in terms of yield and quality characteristics. The yield increased depending on the irrigation and fertilization dose, and the highest value was obtained from the I100 × N150 interaction (28.10 t ha−1). The highest protein yield was determined from the I60 × N150 (2.37 t ha−1) interaction, and the Relative Feed Value (RFV) value was determined from the I30 × N150 (92.17) interaction. Irrigation Water Use Efficiency (IWUE) and Water Use Efficiency (WUE) values increased with decreasing irrigation amount, and the highest IWUE was determined from I30 and the highest WUE was determined from I60 irrigation subjects. According to the field experiments and ANN model, the I80 irrigation with 100 kg ha−1 nitrogen doses would suit the feed yield and quality of Sorghum × Sudan grass hybrid. [ABSTRACT FROM AUTHOR]

Water scarcity, combined with low soil fertility, constitutes one of the main limiting factors in crop productivity in semi-arid regions. However, nutritional supplementation techniques with nitrogen (N) and molybdenum (Mo) can lead to positive enhancements in the production of these crops. The objective was to evaluate the effect of increasing doses of N in the presence and/or absence of Mo on the activity of antioxidant enzymes and the productive increase of forage sorghum subjected to water deficit in the semi-arid region. The experiment was conducted in the field using a randomized block design, with four replications, in a 5 × 2 × 3 factorial scheme, comprising five doses of N (urea): 0, 50, 100, 150, and 300 kg ha−1, two doses of Mo (sodium molybdate): 0 and 160 g ha−1, and three production cycles. The highest yields of green mass (GM) (47.98 Mg ha−1), dry mass (DM) (19.66 Mg ha−1), water use efficiency (WUE) (5.57 kg/m³), and N use efficiency (NUE) (0.26 kg2/g) occurred at the highest N dosage (300 kg ha−1 N). The highest contents and extraction of total N, Mo, chloride (Cl), and potassium (K) were found in regrowth 2 and at the highest N dose (300 kg ha−1). The interaction of N and Mo resulted in higher catalase (CAT) enzyme activity. The meteorological conditions during the cycles strongly influenced the nutrient contents and extraction. The results of the study provide support for producers to use N and Mo fertilization strategies to improve crop productivity, even under water deficit conditions. [ABSTRACT FROM AUTHOR]

Given the scarcity of arable land and water resources in semi-arid regions, it becomes imperative to achieve maximum yield and early maturity for winter grains. In this regard, the present research was conducted to synchronize grain and shoot maturity in high-yielding barley (cv. Behrokh) by reducing nitrogen and deficit irrigation. The experimental factors included three levels of nitrogen (50, 75, and 100% plant nitrogen requirement; PNR) and three levels of irrigation (full irrigation, cutoff irrigation in the milk stage, and dough stage). Results showed that cutoff irrigation and nitrogen fertilizer caused early ripening. The interactions of irrigation and nitrogen were significant for the number of grains/spike, grain yield, straw yield, aboveground biomass, and protein yield. Grain yield in cutoff irrigation in the dough stage plus reducing 25% PNR was similar to full irrigation plus 100% PNR. In full and cutoff irrigation in the dough stage, reducing 25% PNR did not cause a significant change in straw yield. Cutoff irrigation in the dough and milk stages did not cause a significant difference in the grain protein content. In general, it is concluded that to maintain grain, straw yield, and protein quality, it is more appropriate to use 150 kg/ha of nitrogen in the conditions of cutoff irrigation in the dough stage, which could reduce the cost of fertilizer and water in addition to early ripening of the crop and minimize the environmental consequences of consuming these inputs. Early harvesting of barley also helps to prevent summer crops from encountering late-season chilling. [ABSTRACT FROM AUTHOR]

With the increasing world population, global warming, and climate change, water scarcity significantly limits water use in crop production. Therefore, timely and accurate determination of water stress is very important for the correct and effective management of existing water resources and minimizing harmful effects on crop production. Two years of experiments were conducted in the water-limited region in Türkiye to investigate the possible use of the Crop Water Stress Index (CWSI) as a remote sensing technology in sugar beet irrigation scheduling. Four different Irrigation levels (I50: 50% deficit, I75: 25% deficit, I100: full irrigation, and I125: 25% excess irrigation) were applied to sugar beet by drip irrigation system. The amount of applied irrigation water and crop evapotranspiration varied between 238-540 and 350-580 mm in 2021, and between 324- 807 and 502-829 mm in 2022. In both years, the highest beed yields were obtained from I100 treatments (83 and 130 t ha-1) and the lowest from I50 treatments (66.7 and 67.4 t ha-1). Water Productivity (WP) and Irrigation Water Productivity (IWP) in both years decreased significantly by excessive irrigation. CWSI values ranged between 0.16-0.98 in 2021 and between 0.02-0.71 in 2022. CWSI was significantly related to yield and Leaf Area Index (LAI). According to the results, CWSI could be used successfully in sugar beet irrigation scheduling and yield estimation. [ABSTRACT FROM AUTHOR]

Secondary growth in garlic depreciates its visual aspect and thereby renders the crop unviable for trade. Therefore, farmers commonly reduce fertilization and impose drought and oxidative stress caused by high-dose pesticides to reduce secondary growth in garlic plants. However, these procedures can be considered adverse, unhealthy, and environmentally inappropriate. To remedy this scenario, we investigated whether spraying growth inhibitors would prevent secondary growth in garlic plants. First, we evaluated the effects of abscisic acid, trinexapac-ethyl, chlormequat chloride, and paclobutrazol treatments on garlic plants grown in polyethylene tanks (250 m3). We then analyzed the effects of deficit irrigation combined with the application of trinexapac-ethyl (sprayed two or three times) and the application of trinexapac-ethyl, chlormequat chloride, or paclobutrazol alone (each sprayed two or three times) on garlic plants grown in the field, comparing them with the effects of deficit irrigation (control treatment) alone. The in-field experiment was replicated with the following treatments: control (deficit irrigation) and trinexapac-ethyl (sprayed two or three times) treatments. We analyzed the physiological, biometric, and production parameters affecting secondary growth in garlic plants. We observed that trinexapac-ethyl could efficiently regulate secondary growth without causing physiological disturbances in garlic plants. Our results provide valuable information that will contribute to the development of a sustainable technique to replace the current practices used by farmers to prevent secondary growth in garlic plants. [ABSTRACT FROM AUTHOR]

The combined application of biochar and fertilizer has become increasingly popular for improving soil quality and crop productivity. However, the reported research results regarding the effects of biochar on soil properties and crop productivity have contradictory findings, indicating the requirement for further scientific research. Therefore, this study aimed to investigate the effects of a combined application of water hyacinth biochar (WHB) and NPS fertilizer on soil physicochemical properties and wheat yield under deficit irrigation conditions in acidic silty loam soil in Ethiopia. Four different biochar rates (0, 5, 10, and 20 t ha−1), three fertilizer rates (0, 100, and 200 kg NPS ha−1), and two irrigation regimes (50 and 100% of crop requirement) were evaluated to assess soil properties and wheat yields. The results showed that biochar amendment significantly reduced soil bulk density by 15.1–16.7%, and improved soil porosity by 6.8–8.6% and moisture content by 10.3–20.2%. Additionally, the combined application of biochar and fertilizer improved soil pH (0.26–0.87 units), NH4+–N (73.7–144%), NO3−–N (131–637%), and available phosphorus (85.8–427%), compared to the application of fertilizer alone. As a result, wheat dry biomass and grain yield increased by 260 and 173%, respectively. Furthermore, the combined application of WHB and fertilizer resulted in a comparable wheat dry biomass and grain yield even with a 50% reduction of irrigation water. Therefore, WHB has a significant potential to improve soil physicochemical properties and wheat yield when it is applied in combination with fertilizer, and it can reduce the water requirement for wheat production. [ABSTRACT FROM AUTHOR]

Water-saving irrigation is of extraordinary importance for tomato production in semi-arid areas of northwest China. For this purpose, we conducted a two-season trial in a solar greenhouse of two tomato genotypes named '181' and 'Mao Fen 802' and cultivated with substrate, under four irrigation regimes, i.e., well-watered (WW), low (LWD, 80% WW), moderate (MWD, 60% WW) and high (HWD, 40% WW) water deficit. The substrate water content of WW treatment was 75%θf to 90%θf (where θf is the field capacity). The study results showed that the single fruit weight and yield of tomato were significantly declined with an increasing water deficit degree. Compared to WW treatment, the fruit weight and yield were decreased about 34.45% and 20.35% for '181' and 'Mao Fen 802' under HWD treatment, respectively. Conversely, water deficit treatment led to an obvious promotion of WUE and showed an upward trend as the water deficit level increased. In addition, compared to WW treatment, the water deficit significantly decreased the total flavonoids of the '181' tomato by 24.4–93.1%, whereas there was no significant impact on that of 'Mao Fen 802'. Nonetheless, different individual polyphenols were increased by suitable deficit irrigation for two tomato cultivars. Gallic acid, 3,4-dihydroxybenzoic acid, and naringin of '181'tomato were increased by 128.4–195.2%, 8.6–43.7%, and 31–73-fold, respectively, under water deficit compared to WW treatment. Further, under water deficit treatment, p-coumaric acid, benzoic acid, and 3,4-dihydroxybenzoic acid of 'Mao Fen 802' were increased by 36.2–49.2%, 59.1–189.7%, and 36.3–106.4% compared to WW treatment. As the main carotenoid component, the lycopene content of tomato fruit exhibited a significant rise of 7.84–20.02% and 20.55–32.13% for '181' and 'Mao Fen 802' under three degrees of water deficit compared to WW treatment. Linear regression showed a significantly positive relationship between irrigation amounts and yield, and total polyphenols, whereas there was a significantly negative relationship between irrigation amounts and WUE, and total carotenoids. Based on correlation and PCA, WW and LWD, and MWD and HWD, were gathered together for '181', while LWD, MWD, and HWD, were gathered, and only WW scattered for 'Mao Fen 802', along the PC1 direction. It was proposed that 'Mao Fen 802' was more sensitive to water deficit than the '181' tomato. In conclusion, water deficit is conductive to water-saving cultivation of the greenhouse tomato and the tomato genotypes, and water deficit level is a key factor necessary for consideration. [ABSTRACT FROM AUTHOR]

Almond cultivation has a long-standing tradition on the island of Majorca, traditionally practiced under rainfed conditions. Currently, new plantations are established with irrigation; however, due to present conditions and the impacts of climate change, water availability is limited. The Government of the Balearic Islands permits a maximum water supply of 3000 m3 ha−1 per year for almond cultivation. In this study, a 6-year field trial was conducted to investigate the adaptation of fourteen almond cultivars obtained from different research centers under deficit irrigation practices in the soil and climatic conditions of Majorca Island. The cultivars had a significant effect on trunk cross-sectional area TCSA, cumulative almond in-shell yield, cumulative kernel yield, yield efficiency, and shelling percentage. The 'Marta' and 'Tarraco' cultivars exhibited the highest TCSA values. Regarding cumulative almond in-shell yield, 'Glorieta' and 'Constantí' produced the highest yields, whereas the lowest yields were observed in 'Mardía' and 'Tarraco'. In terms of shelling percentage, 'Ferragnès' exhibited the highest value. Kernel quality parameters were cultivar-specific. Additionally, oleic acid content was strongly negatively correlated with linoleic acid content. All cultivars exhibited an unsaturated fatty acid content exceeding 90%, with 'Masbovera' showing the highest value. [ABSTRACT FROM AUTHOR]

The optimization of plant density plays a crucial role in cotton production, and deficit irrigation, as a water-saving measure, has been widely adopted in arid regions. However, regulatory mechanisms governing nitrogen absorption, transportation, and nitrogen use efficiency (NUE) in cotton under deficit irrigation and high plant density remain unclear. To clarify the mechanisms of N uptake and NUE of cotton, the main plots were subjected to three irrigation amounts based on field capacity (Fc): (315 [W1, 0.5 Fc], 405 [W2, 0.75 Fc, farmers' irrigation practice], and 495 mm [W3, 1.0 Fc]). Subplots were planted and applied at three densities: (13.5 [M1], 18.0 [M2, farmers' planting practice], and 22.5 [M3] plants m−2). The results revealed that under low-irrigation conditions, the cotton yield was 5.1% lower than that under the farmer's irrigation practice. In all plant densities and years, the nitrogen uptake of cotton increased significantly with the increase in irrigation. However, excessive irrigation resulted in nitrogen accumulation and migration, mainly concentrated in the vegetative organs of cotton, which reduced the NUE by 9.2% compared with that under farmers' irrigation practice. Concerning the interaction between irrigation and plant density, under low irrigation, the nitrogen uptake of high-density planting was higher, and the yield of seed cotton was only 2.9% lower than that of the control (the interaction effect of farmers' irrigation × plant density), but the NUE was increased by 10.9%. Notably, with the increase in irrigation amount, the soil nitrate nitrogen at the 0–40 cm soil layer decreased, and high irrigation amounts would lead to the transfer of soil nitrate nitrogen to deep soil. With the increase in plant density, the rate of nitrogen uptake and the amount of nitrogen uptake increased, which significantly reduced the soil nitrate nitrogen content. In conclusion, deficit irrigation and high plant density can improve cotton yield and NUE. We anticipate that these findings will facilitate optimized agricultural management in areas with limited water. [ABSTRACT FROM AUTHOR]

High-density olive groves, despite their interesting production potential, have several limitations, including their high fruit load and irrigation requirements. This study aimed to evaluate the effects of fruit load and deficit irrigation on oil yield, fruit quality, and olive chemical composition in a high-density olive grove (cv Sikitita). Our main hypothesis was that primary metabolism, as influenced by crop load and stress, could modify the accumulation of different phenolic classes. Different fruit loads were generated through flower thinning (66%, 50%, 33%, 0%), and two deficit irrigation treatments (−60%, −75%) were compared to the well-watered control (920 m3/ha). Thinning treatments had a limited effect on oil yield; on the other hand, deficit irrigation caused considerably less oil accumulation in the fruit on all sampling dates. Thinning 66% and deficit irrigation 75% were considered with the control for untargeted metabolomic analysis, including three sampling dates. A total of 233 distinct phenolic compounds were annotated. Multivariate HCA results indicated that harvest time had an impact on the phenolic profile of olive fruits, obtaining two separated clusters that grouped t1 and t2 together and apart from t3, which clustered independently. Regarding agronomic techniques, they played a differential role in the phenolic profile (supervised OPLS-DA). Fruit load mostly affected flavonoid glycosides. In contrast, the phenolic response to deficit irrigation was more heterogeneous, with phenolic acids (35%), flavonoids (25%), LMW, and other phenols (25%). [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) and melatonin (MEL) are affordable and effective phytohormones that help mitigate environmental stress. However, the combined benefits of SA and MEL in managing salt and drought stress in lettuce have not been evaluated. Therefore, this study was designed to evaluate the effectiveness of foliar spraying with 1.0 mM SA and 100 µM MEL, either alone or in combination, to enhance lettuce yield, growth, photosynthetic pigments, mineral status, quality, and antioxidant response under four different irrigation regimes. The irrigation practices used were: full irrigation (FI, irrigated with 0.18 dS m −1 at 100 % field capacity [FC]), deficit irrigation (DI, irrigated with 0.18 dS m −1 at 75 % FC), saline irrigation (SW, irrigated with 2.5 dS m −1 at 100 % FC), and deficit saline irrigation (DSW, irrigated with 2.5 dS m −1 at 75 % FC). Additionally, a control treatment (CK) was carried out with foliar application of distilled water and irrigation at 0.18 dS m −1. Compared to the CK, the application of SA, MEL, and SA+MEL increased evapotranspiration by 4.3 %, 8.6 %, and 15.1 %, and yield by 10.2 %, 16.4 %, and 23.8 %, respectively, under FI conditions. Furthermore, the joint application of SA and MEL at FI showed 25.3 % and 20.2 % higher K +/Na+ and Ca2+/Na+ ratios, respectively, compared to the CK. Additionally, the co-application of SA+MEL improved chlorophyll a, b, and carotenoid levels by 19.2 %, 17.2 %, and 20.4 %, respectively, under FI conditions, compared to the CK. Exogenous application of SA, MEL, and SA+MEL also improved total soluble solids by 17.3 %, 18.5 %, and 11.1 % and reduced nitrate content by 9.7 %, 10.4 %, and 13.5 % in lettuce under FI conditions, compared to the CK. The application of SA+MEL together resulted in a more pronounced increase in vitamin C content compared to supplying SA and MEL individually. Moreover, under DSW conditions, exogenous application of SA, MEL, and SA+MEL decreased the membrane stability index by 13.7 %, 9.4 %, and 6.3 %, increased malondialdehyde by 65.4 %, 40.8 %, and 36.6 %, and increased proline content by 68.4 %, 65.4 %, and 96.4 %, respectively, compared to the CK. Moreover, exogenous SA+MEL significantly increased the activities of superoxide dismutase, catalase, peroxidase enzymes under both SW and DSW conditions compared to the SA or MEL. Conversely, the activity of ascorbate peroxidase enzyme showed a gradual decrease in DI, SW, and DSW conditions, relative to the FI conditions. In conclusion, the integrated application of SA+MEL is an optimal strategy to enhance yield, morpho-physiological traits, nutrient homeostasis, antioxidant capacity, and quality in lettuce and mitigate the adverse effects of drought, salinity, and drought-salinity stress. [Display omitted] • Deficit saline irrigation has the most adverse effect on lettuce yield. • SA and MEL enhanced lettuce tolerance to drought and salinity stress. • Joint use of SA (1.0 mM) and MEL (100 µM) more effectively alleviates stress in lettuce. • SA+MEL improved the nutrient homeostasis and antioxidant capacity of lettuce. • SA+MEL combination increased vitamin C and decreased the nitrate content of lettuce. [ABSTRACT FROM AUTHOR]

Jojoba (Simmondsia chinensis) is cultivated for its seeds, which contain a high-value liquid wax. There is little known regarding irrigation requirements of intensively cultivated jojoba. The project's objectives were to evaluate the effects of irrigation regime on water status, growth, yield, and water productivity (WP, wax yield per unit of water applied) of intensely cultivated jojoba. An experiment was conducted over six years in a 14-year-old commercial plantation in Israel's Northern Negev Desert. Treatments included: Control irrigation according to best commercial practice of returning reference evapotranspiration multiplied by a crop coefficient (Kc) of 0.5; Low irrigation providing 75% (Kc = 0.375) of the control; High irrigation providing 125% (Kc = 0.625) of the control; Regulated deficit irrigation (RDI) according to the control treatment, terminated for one to two months, after the wax accumulation stage. Stem water potential (SWP) consistently indicated jojoba water status. Increasing water application from − 25% to the control and further to + 25% led to augmented vegetative growth and number of seeds, but yield was increased at rates lower than the differences in water application by the treatments, such that WP was negatively associated. Effects on yield were limited to higher yielding 'On' years. The RDI treatment resulted in yield not different from the control and 15% higher WP, but significantly inhibited seed removal during mechanical harvesting. The results suggest commercial potential for increasing profits through water savings. Further research is needed to determine RDI regimes without detrimental effects on harvesting efficiency. [ABSTRACT FROM AUTHOR]

To better understand the implications of climate change, the combined responses of olive trees to irrigation amount and warming need to be examined. Thus, the objective was to evaluate the effects of moderate deficit irrigation and warming during late winter and spring on vegetative growth and biomass, full bloom timing and intensity, and yield components in young olive trees. Two three month-long experiments were conducted using open top chambers with four treatment combinations: 100% irrigation with a control temperature; 100% irrigation with 4 °C warming; 50% irrigation with a control temperature; and 50% irrigation with 4 °C warming. The trees were potted two-year-old, cv. Arbequina trees in the 2018 experiment and three-year-old, cv. Coratina trees in the 2019 experiment. Flowering was low in the young cv. Arbequina trees in 2018, but it was much greater in the older cv. Coratina trees in 2019. Overall, lower flowering intensity and fruit set or more parthenocarpic fruit contributed to less viable fruit number with warming. These reproductive variables were less affected by deficit irrigation. In contrast, shoot growth and vegetative biomass were decreased by deficit irrigation in cv. Arbequina (2018) when fruit number was low in all trees with less response due to warming. In cv. Coratina (2019), the lower fruit number in warmed compared to control trees contributed to greater individual fruit weight at the end of the experimental period, and few significant effects of either deficit irrigation or warming on shoot growth were observed. Fruit yield was greater in the well-irrigated, temperature control than in the other treatment combinations in cv. Arbequina, while warming reduced fruit yield in cv. Coratina. From a production perspective, it does not appear that many early reproductive responses to warming can be easily counteracted by adjusting irrigation. Further studies with more mature trees and cultivars over several growing seasons are recommended. [ABSTRACT FROM AUTHOR]

Super-high density olive orchards may increase profitability for table olive producers. However, water needs and fruit damage could limit their viability. Deficit irrigation scheduling would reduce the amount of water required, but rehydration before harvest is extremely important. The aim of this work was to compare a typical deficit farm management model with a regulated deficit irrigation one based on the plant water status. The experiment was carried out during three seasons in a three years-old (4 × 1.5 m) commercial table olive orchard. In both irrigation scheduling plots, seasonal amount of applied water was similar. Irrigation treatments were: common farm management (CFM), an almost constant rate of irrigation, and Regulated deficit (RDI) based on midday shaded water potential. Vegetative measurements suggested that RDI increased the external surface of the hedge, and this was related with greater yield in this treatment. Significant differences were found in of fruit size at harvest in some seasons, with larger fruits in RDI compared to CFM. However, fruit damage occurred during mechanical harvest in both irrigation managements, despite the higher skin firmness in RDI, and shows the need to carry out postharvest treatments to improve the quality of the final product. Accurate control of the tree water status would allow optimizing the amount of water available for table olive orchards. [ABSTRACT FROM AUTHOR]

Climate change represents one of the current major challenges and the improper use of water resources is an impeding threat. Agricultural research can play a crucial role by developing innovative strategies and techniques to reduce water use without affecting crop productivity and quality, particularly in grapevine growing in Mediterranean areas, as both productivity and wine quality are quintessential for the economic and ecologic sustainability of this crop. The present study aimed to define a deficit irrigation strategy for the "Primitivo" grapevine cultivar, taking into account the overall pathway of the vineyard performance in terms of leaf functionality, starch reserves, vine productivity, and wine quality. The trial was carried out in Southern-Italy on a three year-old, drip irrigated vineyard, imposing four deficit irrigation regimes for two consecutive seasons, consisting of 29 (T29), 55 (T55), 85 (T85) and 100% (T100) of crop evapotranspiration (ETC). Mild water restriction (T85) did not affect vegetative nor reproductive vine performance. Deficit irrigation at 55% ETC lowered leaf functionality, starch accumulation, vine vigour and yield, due to a reduction of cluster weight; however, wine acidity and phenolic compounds were increased. T29 further decreased yield, as also the number of clusters was reduced. The most water-stressed treatment revealed a low concentration of malic acid in the must and a consequent increase of the ethanol sensation in the wine. After 9 months ageing, T85 had the highest wine colour intensity suggesting this treatment as the most promising in terms of quality and quantity of wine as well as for water saving. [ABSTRACT FROM AUTHOR]

The olive tree (Olea europaea L.) is culturally and economically vital in Morocco. However, its sustainability is threatened by aridity and water scarcity. Studying its response to different irrigation strategies is crucial for sustainable cultivation and improved water use efficiency in the face of future drought events. This work aimed to study the responses of sap flow rate, physiological, and agronomic parameters of the Moroccan olive cultivar 'Menara' to Regulated Deficit Irrigation (RDI) and Sustained Deficit Irrigation (SDI) strategies. Seven irrigation regimes were studied based on the sensitivity of phenological phases to water stress, distinguished as (SP) 'Sensitive Period' and (NP) 'Normal Period'. SP involves flowering (SP1) and oil synthesis to harvest (SP2), while NP relates to pit hardening. 'Menara' olive trees were subjected to four RDI treatments: T1 (SP 100- NP 70% ETc), T2 (SP 100- NP 60% ETc), T3 (SP 80- NP 70% ETc), and T4 (SP 80- NP 60% ETc), and two SDI treatments: T5 (70% ETc) and T6 (60% ETc), compared with control (T0) trees under full irrigation (100% ETc). In comparison to the control T0, the deficit irrigation treatments exhibited lower sap flow rates. Specifically, T1 and T2 experienced reductions of 10% and 19% in sap flow rates, respectively, attributed to a decrease in water application of 11% and 14% compared to T0. Despite this decline, T1 and T2 demonstrated fruit yields comparable to T0. Conversely, T4, which received 28% less irrigation, displayed a yield reduction of approximately 23% compared to T0 in 2022. Moreover, adverse effects were observed in Menara olive trees treated with T4 after two consecutive seasons of deficit irrigation in 2023, indicating that prolonged stress effects could be detrimental in subsequent years. T3, under RDI, showed resilience with a 13% reduction in production despite a 37% decrease in sap flow rate and a 24% water restriction. Conversely, T5 and T6, employing SDI, experienced significant yield declines of 50%, with reductions in water application of 30% and 40% and sap flow rate of 51% and 80%, respectively, in 2022. The alternate bearing pattern significantly impacts Menara olive production, as evidenced by reduced sap flow and yield in the "off" year of 2023, regardless of irrigation strategies. A strong correlation (R2 = 0.84) between sap flow and yield indicates that well-irrigated olive trees tend to transpire more, leading to higher yields. Stomatal conductance (gs) notably decreases with increased water deficit, with reductions of 8%, 12%, and 23% observed in T4, T5, and T6, respectively. Furthermore, a significant reduction in FV/FM, indicative of water stress, was observed with a 40% decrease in water supply in the T6 treatment group during both irrigation seasons in 2022 and 2023, with Fv/Fm reaching approximately 0.7. In general, Menara olive trees subjected to deficit irrigation, particularly under the T3 RDI treatment, showed the ability to adapt and cope with low water supply over time. However, the cumulative water shortage effect of the SDI treatment T6 resulted in a decline in both the agronomic and physiological performance of this cultivar. [ABSTRACT FROM AUTHOR]

Climate change has become a concern, emphasizing the need for the development of crops tolerant to drought. Therefore, this study is designed to explore the physiological characteristics of quinoa that enable it to thrive under drought and other extreme stress conditions by investigating the combined effects of irrigation water levels (100%, 75%, and 50% of quinoa's water requirements, WR as I1, I2 and I3) and different planting methods (basin, on-ridge, and in-furrow as P1, P2 and P3) on quinoa's physiological traits and gas exchange. Results showed that quinoa's yield is lowest with on-ridge planting and highest in the in-furrow planting method. Notably, the seed protein concentrations in I2 and I3 did not significantly differ but they were 25% higher than those obtained in I1, which highlighted the possibility of using a more effective irrigation method without compromising the seed quality. On the other hand, protein yield (PY) was lowest in P2 (mean of I1 and I2 as 257 kg ha−1) and highest in P3 (mean of I1 and I2 as 394 kg ha−1, 53% higher). Interestingly, PY values were not significantly different in I1 and I2, but they were lower significantly in I3 by 28%, 27% and 20% in P1, P2, and P3, respectively. Essential plant characteristics including plant height, stem diameter, and panicle number were 6.1–16.7%, 6.4–24.5%, and 18.4–36.5% lower, respectively, in I2 and I3 than those in I1. The highest Leaf Area Index (LAI) value (5.34) was recorded in the in-furrow planting and I1, while the lowest value was observed in the on-ridge planting method and I3 (3.47). In I3, leaf temperature increased by an average of 2.5–3 oC, particularly during the anthesis stage. The results also showed that at a similar leaf water potential (LWP) higher yield and dry matter were obtained in the in-furrow planting compared to those obtained in the basin and on-ridge planting methods. The highest stomatal conductance (gs) value was observed within the in-furrow planting method and full irrigation (I1P3), while the lowest values were obtained in the on-ridge and 50%WR (I3P2). Finally, photosynthesis rate (An) reduction with diminishing LWP was mild, providing insights into quinoa's adaptability to drought. In conclusion, considering the thorough evaluation of all the measured parameters, the study suggests using the in-furrow planting method with a 75%WR as the best approach for growing quinoa in arid and semi-arid regions to enhance production and resource efficiency. [ABSTRACT FROM AUTHOR]

Improving drought resistance in Zoysiagrass (Zoysia spp.) is a target for both private and public breeding programs. The performance of 26 elite experimental zoysiagrasses was compared under progressive drought stress with Palisades, Diamond, and Zeon. Environmental conditions were warmer and drier in 2020 (66 days) than 2021 (45 days). Irrigation was applied once weekly using potential evapotranspiration (ETo) rates and crop coefficients (Kc) of 0.6 (non‐stress), or 0.40, 0.30, and 0.25 deficit treatments. Turfgrass quality, leaf wilt, normalized difference vegetative index, normalized difference red edge, and volumetric water content were recorded weekly. Genotypes with the highest means (statistical “a” group) contributed to a turfgrass performance index (TPI). Elite zoysiagrass with TPI ≥ Palisades (19) were Zoysia japonica Steud. ecotypes DALZ 1311 (22), 1601 (19), and 1603 (21), and finer textured interspecific hybrids, DALZ 1701 (18), 1713 (26), 1714 (18), and 1801 (24). Relative to an irrigation schedule using a 0.6 Kc, these genotypes survived extreme deficit irrigation, which conserved 40.1% (45,859.6 L) and 66.4% (44, 592.2 L) of water in 2020 and 2021, respectively. Overall, this study demonstrated that significant water consumption could be reduced with proper cultivar selection and deficit‐based irrigation management while maintaining an acceptable turfgrass quality under drought conditions. [ABSTRACT FROM AUTHOR]

Background: To optimize irrigation water use and productivity, understanding the interactions between plants, irrigation techniques, and fertilization practices is crucial. Therefore, the experiment aims to assess the effectiveness of two application methods of potassium humate combined with chelated zinc under partial root-zone drip irrigation techniques on maize nutrient uptake, yield, and irrigation water use efficiency across two irrigation levels. Methods: Open-field experiments were carried out in two summer seasons of 2021 and 2022 under alternate and fixed partial root-zone drip irrigation techniques to investigate their impacts at two irrigation levels and applied foliar and soil applications of potassium humate or chelated zinc in a sole and combinations on maize. Results: Deficit irrigation significantly increased hydrogen peroxide levels and decreased proline, antioxidant enzymes, carbohydrate, chlorophyll (a + b), and nutrient uptake in both partial root-zone techniques. The implementation of combined soil application of potassium humate and chelated zinc under drought conditions on maize led to varying impacts on antioxidant enzymes and nutritional status, depending on the type of partial root-zone technique. Meanwhile, the results showed that fixed partial root-zone irrigation diminished the negative effects of drought stress by enhancing phosphorus uptake (53.8%), potassium uptake (59.2%), proline (74.4%) and catalase (75%); compared to the control. These enhancements may contribute to improving the defense system of maize plants in such conditions. On the other hand, the same previous treatments under alternate partial root zone modified the defense mechanism of plants and improved the contents of peroxidase, superoxide dismutase, and the uptake of magnesium, zinc, and iron by 81.3%, 82.3%, 85.1%, 56.9%, and 80.2%, respectively. Conclusions: Adopting 75% of the irrigation requirements and treating maize plants with the soil application of 3 g l−1 potassium humate combined with 1.25 kg ha−1 chelated zinc under alternate partial root-zone technique, resulted in the maximum root length, leaf water content, chlorophyll content, yield, and irrigation water use efficiency. [ABSTRACT FROM AUTHOR]

One of the main challenges in super high-density olive is maintaining hedgerow structure suitable for mechanical harvesting. Deficit irrigation strategies (DI) can contribute to this maintenance. In this study, three DI treatments at 50% of the Control (DI-1: budbreak to pre-bloom, DI-2: fruit set to pit hardening, and DI-3: pit hardening to harvest) were applied to 6-year-old Arbequina hedgerows in a semi-arid environment of Argentina over three consecutive seasons. The mean applied water reduction was 12% for DI-1 and 16% for DI-2 and DI-3, compared to Control (100% of ETc throughout the cycle). DI-3 achieved the narrowest hedgerows at harvest, where canopy height was responsive to irrigation and canopy width was affected by fruit load but not by the irrigation regime. DI-1 demonstrated similar fruit and oil yields to Control throughout the experiment, while DI-2 only had comparable yields to Control in Off-season. DI-3 had the lowest oil yields, averaging – 27% in Off and On-seasons. The fruit number was similar among treatments in all seasons, indicating that differences in final yield were related to fruit size and oil concentration. Further studies are needed to determine the optimal duration and intensity of the water deficit for DI-3. [ABSTRACT FROM AUTHOR]

Agricultural drainage water production in southwestern Iran is a serious problem, but this low-quality water can be considered a potential alternative source of freshwater. In this regard, the cultivation of salinity-resistant plants using drainage water can be considered a suitable measure. Quinoa (Chenopodium quinoa Willd.) is a valuable halophyte, and the World Health Organization has recognized it as a plant that can guarantee the world's future food security. For this purpose, this study was conducted to investigate the sustainable use of drainage water for quinoa cultivation (2019–2020). First, quinoa seed germination experiments were conducted in the laboratory using four different salinity solutions [0 (control), 9, 18, and 27 dS/m ]. Then, field research was conducted in the form of a split-plot factorial design so that irrigation management and planting date were implemented as the main treatments and genotype factor as subtreatment in small plots. Four genotypes of quinoa were planted on the research farm on three dates, January 20 (D1), February 5 (D2), and February 20 (D3). Irrigation managements include irrigation with water from the Karun River (as freshwater, I1), drainage water from sugarcane fields (I2), and alternating irrigation with freshwater and drainage water (I3). An average reduction of 4% in the total germination at 27 dS/m salinity compared to the control treatment indicated that quinoa was well adapted to salinity during germination. The highest biomass was produced by the Rosada genotype cultivated on the D3 under I1 management at a rate of 540 g/m2 , followed by the Q26 genotype cultivated on the D1 under I3 management (499 g/m2). Finally, it can be concluded that, to maintain the salt balance in the soil, leaching at the end of the growing season is necessary to remove salts and maintain sustainable haloculture. [ABSTRACT FROM AUTHOR]

Maize is vital in Ethiopia, particularly in Jimma. However, the benefits of deficit irrigation (DI) under varying nitrogen rates (NRs) for maize remain unknown. A 3-year field experiment assessed maize response to different NRs (N0=0 kg ha−1 , N23=23 kg ha−1 , N46=46 kg ha−1 , N69=69 kg ha−1 , and N92=92 N kg ha−1) under three DI levels (I50=50 , I75=75 , and I100=100% ETc). Factors such as rain-fed findings, soil testing, and local recommendations were considered in determining these rates. The results showed significant effects of DI, NR, and their interactions on grain yield, biomass, water-use efficiency (WUE), nitrogen-use efficiency (NUE), and harvest index (HI). Without nitrogen, 50% DI led to a greater than 50% reduction in yield and biomass compared with that at I100×N0. However, WUE and HI increased at I50×N92 compared with I100×N0. Increasing irrigation and nitrogen levels improved yield and biomass. Optimal WUE was achieved with irrigation close to 75% ETc without compromising yields. Agronomic yield significantly improved with NR above 92 kg N ha−1 under mild deficit and full irrigation, but higher rates did not provide additional benefits under severe deficit conditions. The economically optimum nitrogen rate ranged from 78 to 80 kg N ha−1 for irrigation levels ranging from 50% to 100% ETc. The study suggests that applying 80 kg N ha−1 with 75%–100% ETc levels is the best approach to enhance maize yield and achieve economic benefits. Further research is needed to explore DIs below 50% and above 100% ETc, as well as nitrogen fertilization rates above 92 kg ha−1 , in order to optimize maize production in the region. Practical Applications: This study examined the benefits of deficit irrigation and fluctuating nitrogen rates for maize production in Jimma, Ethiopia. By adopting deficit irrigation strategies and adjusting nitrogen rates, producers can reduce water withdrawal by approximately 25%. This approach optimizes both water-use efficiency and nitrogen-use efficiency without compromising yields. Increasing irrigation and nitrogen rates above I100×N92 improves agronomic yield, whereas reducing them below I50×N46 significantly decreases yield and WUE. Economically optimum nitrogen rates range from 78 to 80 kg N ha−1 with 50%–100% full irrigation. Balancing input costs and potential benefits is crucial for optimizing irrigation and nitrogen rates for maize production. To maximize agronomic yield, full irrigation with 92 kg N ha−1 (less than 96 kg N ha−1) is advisable. To optimize water use, 75% of full irrigation with 92 kg N ha−1 is recommended. To optimize nitrogen (economic yield) and achieve higher net returns, fully irrigating the maize crop with 80 kg ha−1 of nitrogen fertilization is advised. Farmers should adapt these findings to local conditions, considering factors such as soil characteristics, nitrogen price, and water price, and should consult local experts. Further research is needed to explore the effects of more or less than 50% full irrigation and of nitrogen doses exceeding 92 kg ha−1. [ABSTRACT FROM AUTHOR]

Sensitive irrigation programming requires both a good knowledge of plant physiology regarding water use and the monitoring of the effect of water stress on plant physiology. In this study, the effect of different irrigation strategies on full-grown olive trees of the Memecik variety irrigated by the drip irrigation method was investigated over three crop seasons (2012–2013, 2013–2014, and 2014–2015), and the possibility of using these strategies in forming an irrigation program was examined. The experiment consisted of five irrigation treatments with three replications in a random block design. One significant finding after the three years of observation in the study was that it was possible to determine in a simple and sensitive way the temporal responses of olive trees under conditions of water stress with predawn plant water potential, stomatal conductance, and plant water stress index but not chlorophyll content (SPAD value). Statistically significant differences were found between the treatments in the measurements made. Taking into account the three-year averages of treatment values for water applications, acceptable threshold values for predawn plant water potential, stomatal conductance, and plant water stress index are −1.64 MPa , 330 mmol m−2 s−1 , and 0.37, respectively. It is easy to put these measurements into practice, and doing so will enable very significant water savings in Mediterranean climate conditions. [ABSTRACT FROM AUTHOR]

• Drought caused wheat genotype specific decreasing trend in various agronomic traits. • Genotype-specific variations were observed in defense system under drought stress. • Better stress tolerance indices were found in BS3, BS4, BS8, BS9 and BS20 genotypes. • Both physio-biochemical and agronomic traits can be considered in breeding programs. In parallel with rapid growth in human population, increasing deficiency of water for irrigation along with abruptly changing environmental conditions has increased the food insecurity problem which needs immediate attention to secure the future food security. This study aimed to identify the water stress tolerance and high yielding potential of newly developed wheat genotypes, based on agronomic, morphological and biochemical aspects, along with the stress tolerance indices (STI). These genotypes were developed through conventional breeding from a cross (Bhakkar x S-24) and named as BS following the names of the parental genotypes. The experiment comprised a total 20 newly developed genotypes and 2 parental genotypes. Split plot field experiment was conducted using reduced number of irrigations as water stress treatment. All studied genotypes exhibited distinct negative impacts of deficit irrigation with respect to various studied agronomic attributes but was genotype specific. There were genotype-specific variations to deficit irrigation, regarding leaf chlorophyll contents, water relations, membrane lipid peroxidation, as well as antioxidative defense mechanism. Under deficit irrigation genotypes BS3, BS4, BS8, BS9, and BS20 demonstrated superiority in growth and grain yield related attributes that was attributed to their effective performance in maintaining better water content through better osmotic adjustment, chlorophyll levels, as well as better defense against oxidative stress. Comparatively less reductions in growth and yield i.e 26.43 % and 30.56 %, 28.94 % and 28.01 %, 32.13 % and 30.07 %, 34.35 % and 31.36 %, and 24.14 % and 26.55 % were recorded in BS3, BS4, BS8, BS9, and BS20 respectively as compared with remaining genotypes. However, the opposite was true for genotypes BS7, BS13, BS15 followed by BS6 and BS7. Stress tolerance indices also showed the better tolerance of the genotype BS3, BS4, BS8, BS9 and BS20. In conclusion, breeding programs for the development of stress-tolerant wheat genotypes should also consider the physio-biochemical mechanisms alongside the agronomic traits. This holistic approach will contribute significantly for the selection of genotypes that exhibit resilience to water deficit stress with high yield potential. [ABSTRACT FROM AUTHOR]

The water footprint is an increasingly demanded environmental sustainability indicator for certifications and labels in agricultural production. Processing tomatoes are highly water-intensive, and existing studies on water footprint have uncertainties and do not consider the impact of different irrigation configurations (e.g., surface drip irrigation (SDI) and subsurface drip irrigation (SSDI)) and irrigation strategies. This study presents a two-year experimental investigation to determine the water footprint of processing tomatoes grown in southern Spain (Andalusia) and the impact of SSDI and deficit irrigation. Five irrigation treatments were established: SDI1 (surface drip irrigation without water limitation), SDI2 (surface drip irrigation without water limitation adjusted by soil moisture readings), SSDI1 (subsurface drip irrigation without water limitation and a dripline depth of 15 cm), SSDI2 (similar to SSDI1 but with mild/moderate water deficit during the fruit ripening stage), and SSDI3 (subsurface drip irrigation without water limitation and a dripline depth of 35 cm (first year) and 25 cm (second year)). Measurements included crop vegetative growth, leaf water potential, leaf gas exchange, nitrate concentration in soil solution, and crop yield and quality. The soil water balance components (actual evaporation, actual transpiration, deep drainage), necessary for determining the total crop water footprint, were simulated on a daily scale using Hydrus 2D software. Results indicated that SSDI makes more efficient use of irrigation water than SDI. The water footprint of SSDI1 was 20–35% lower than that of SDI1. SSDI2 showed similar water footprint values to SDI1 under highly demanding environmental conditions and significantly lower values (≈40%) in a year with lower evaporative demand. The dripline depth in SSDI was critical to the water footprint. With a 35 cm installation depth, SSDI3 had a significantly higher water footprint than the other treatments, while the values were similar to SSDI1 when the depth was reduced to 25 cm. [ABSTRACT FROM AUTHOR]

The efficient use of phosphate fertilizers and optimization of the amounts of irrigation water can maximize tomato growth and fruit production. This study aimed to evaluate the effects of different phosphorus (P) doses and sources on the growth and production components of tomato plants of the cultivar Gaúcho Melhorado Nova Seleção subjected to different irrigation water percentages. To achieve this, we set up an experiment using a factorial design to test the effects of four doses of P2O5 (corresponding to 25%, 50%, 100%, and 200% of the recommended dose), two P sources (monoammonium phosphate—MAP and organomineral—OM), and four irrigation water percentages (50%, 75%, 100%, and 125% of field capacity). Tomato plant growth improved when water was supplied at a percentage close to 100% of field capacity, with increased plant height, leaf length, and number of flowers observed (increases of 11.95%, 7.33%, and 13.87%, respectively, compared to 50% of field capacity). However, both excess and deficit irrigation resulted in morphological changes in tomato plants. Additionally, we observed that OM was more effective than MAP in increasing plant diameter and number of flowers, with increases of up to 36.4% and 227.6%, respectively, when using OM. Conversely, tomato growth was negatively affected by higher doses of MAP doses, suggesting that 25% of the recommended dose may yield the best growth rates. We verified that tomato plants can compensate for low phosphorus doses by increasing productivity with higher water amounts (125%–42.40 t ha−1), but high phosphorus doses result in greater fruit production with lower water percentages (50%–41.52 t ha−1). [ABSTRACT FROM AUTHOR]

Water deficit priming through regulated deficit irrigation has been shown to be beneficial for peanut cultivation, leading to improved water‐use efficiency during the crop cycle and enhanced stress acclimation. The effects of priming using water deficit can be heritable, but little is known about stress priming effects on the physiology and growth of successive generations undergoing water stress. Two experiments were conducted to assess cross‐generational priming by determining physiological and growth responses of offspring of primed and non‐primed peanut plants of two genotypes, COC‐041 and New Mexico Valencia C (NMV‐C), both previously found to be strongly responsive to priming. Seeds were collected from parental plants subjected to mild water stress by regulated deficit irrigation (primed) or adequate irrigation (non‐primed). These seeds were then planted, and the offspring were monitored for physiological and growth responses to water stress, including on a whole‐plant basis using a high‐throughput physiological phenotyping platform and on individual leaves by periodic single‐leaf measurements. Measurements included whole‐plant transpiration (plant‐Tr), root water uptake, leaf transpiration, stomatal conductance and net CO2 assimilation (leaf‐Tr, leaf‐gs, and leaf‐A), leaf water and osmotic potential (leaf‐Ψw and leaf‐Ψo), leaf osmotic adjustment, leaf relative water content (leaf‐RWC) and cumulative plant‐Tr. Offspring of both genotypes from primed parent plants had faster early establishment, with more uniform germination, and more rapid initial seedling growth compared to offspring from non‐primed parent plants. Although offspring of both non‐primed and primed plants of both genotypes exhibited a significant reduction of plant‐Tr, gas exchange, leaf‐Ψw, leaf‐Ψo, and leaf‐RWC when exposed to water stress, offspring of primed plants showed increased water use efficiency through reduced leaf‐gs, leaf‐Tr and plant‐Tr while maintaining leaf‐A under water stress. Despite offspring of both primed and non‐primed plants being susceptible to severe water stress, offspring of primed plants exhibited overall enhanced water use efficiency, leading to greater dry biomass production per gram of transpired water and a trend of less growth reduction due to water stress compared to offspring of non‐primed plants, especially for the genotype COC‐041. This study shows the potential of water deficit priming to promote cross‐generational changes in physiological function under limited water availability, by enhancing crop stress acclimation in the next plant generation. [ABSTRACT FROM AUTHOR]

The impact of drought stress on productivity of cotton (Gossypium hirsutum L.) is a well‐known challenge in agricultural production, and concurrently, the question of whether using the same or different selection criteria in well‐watered and water‐deficit conditions to select drought‐tolerant cotton varieties remains unclear. This study aimed to comprehensively assess the single plant progeny lines within the F6 and F7 generations for determine response to DS and select the tolerant lines within the F7 generation. Single plant progeny rows were established, with the deficit water condition comprising 108 and 136 single plants for the F6 and F7 generations, respectively, and the WW condition consisting of 120 and 156 single plants for the F6 and F7 generations, respectively, with four blocks in Augmented experimental design. These progeny rows have length of 12 m, incorporate five control varieties (Karizma, Gloria, Carla, Candia and Claudia) to facilitate a comprehensive comparison. The study findings showed that fibre length, boll number and lint percentage were identified as the most crucial selection criteria under both WW and deficit irrigation conditions through principal component analysis. These indicators are highly beneficial for evaluating cotton's drought tolerance and screening potential drought‐tolerant lines under both irrigation scenarios. According to the decision tree analysis, FL and BN have emerged as the most critical decision‐making parameter in both irrigation conditions. Furthermore, the analysis revealed that each selection criterion has different impact in the comprehensive selection process. Also, as a result of all statistical analysis results and breeder observations, a total of 10 cotton lines were selected in the F7 generation. These selected genotypes hold promise for future cotton breeding programmes, providing an avenue to enhance drought tolerance and elevate cotton yield and productivity. Clinical Trial Registration: This study does not involve a clinical trial, and therefore, clinical trial registration is not applicable. [ABSTRACT FROM AUTHOR]

Drought has a significant impact on plants, affecting their growth, development and survival. This study focuses on evaluating the impact of drought stress, a significant abiotic factor, on the agronomic and fiber parameters of potential cotton (Gossypium hirsutum L.) lines with the aim of developing drought-tolerant varieties. The experiment involved two irrigation regimes—well-watered (100% field capacity) and deficit irrigation (50% field capacity)—conducted on F9–F10 generations. Key fiber parameters, including fiber length, boll weight, fiber strength, and lint percentage, were identified as crucial selection criteria under both well-watered and deficit irrigation conditions. Notably, boll number emerged as the decisive parameter in both F9 and F10 generations. The study employed univariate and multivariate analyses, such as PCA, heat map cluster, correlation analysis, and decision tree, which consistently highlighted fiber length, boll weight, fiber strength and lint (ginning) percentage the key factor. In the F10 generation, the integration of decision tree and heat map cluster results led to the identification of 8 promising lines. These selected genotypes have potential for inclusion in future cotton breeding programmes, offering the opportunity to increase drought tolerance and improve cotton yield and productivity. Their resilience to environmental stresses makes them promising candidates for improving overall cotton performance under challenging conditions. [ABSTRACT FROM AUTHOR]

Water stress causes various plant morphological, physiological, and biochemical responses. Silicon application may reduce the water stress tolerance in plants by increasing the physiology parameters and the crop's vegetative growth. Hence, the study aims to evaluate the effect of water stress levels on Alternanthera sissoo, known as Brazilian spinach, and determine which silicon (Si) level is the best under water scarcity. The method implied measuring the water stress by different levels of water level applied to the plant which are 100 % (well-watered), 75 % (moderate water deficit), 50 % (high water deficit), and 25 % (severe water deficit). The variation of silicon concentrations is S0 (control), S1, S2 and S3 (0, 0.6, 0.9 and 1.2 %v/v) arranged in the Randomized Complete Block Design (RCBD) in the greenhouse. Growth, physiological, and biochemical parameters were analyzed during the experiment. The research findings showed that water stress results were statistically reduce the leaf area, leaf number root length, fresh weight, chlorophyll content, relative water content (RWC), and malondialdehyde (MDA). The root length, leaf area, and malondialdehyde (MDA) show the interaction between water stress level and silicon concentration. The study proposed that the Si nutrient management strategy has the potential to minimize the impacts of drought stress in Brazilian spinach. Regarding research findings, it was determined that the optimal water requirement for Alternanthera sissoo is 50 % of the water treatments, with a silicon concentration of 1.2 %v/v. This is essential for better water management of the plant. [ABSTRACT FROM AUTHOR]