Irrigation Treatments Research Articles

Superiority of native seed core microbiomes in the suppression of bacterial wilt disease

IntroductionNative endophytic microorganisms in tobacco seeds are closely related to their resistance to Ralstonia solanacearum (R. solanacearum) infections. However, the role of the native seed core microbiome in the suppression of bacterial wilt disease (BWD) remains underexplored.MethodsThe characteristics of endophytic bacterial communities in both resistant and susceptible tobacco varieties were characterized using high-throughput sequencing technology.ResultsThis study found Paenibacillus as a potential microbial antagonist against BWD based on its significantly greater presence in BWD-resistant tobacco varieties, with a relative abundance that was 83.10% greater in the seeds of resistant tobacco than in those of susceptible varieties. Furthermore, a Paenibacillus strain identified as Paenibacillus odorifer 6036-R2A-26 (P. odorifer 26) was isolated from the seeds of the resistant variety. Following irrigation treatment with P. odorifer 26, the BWD index was reduced by 51.08%. Additionally, this strain exhibited significant growth-promoting effects on tobacco. It significantly increased the fresh weight of the tobacco plants by 30.26% in terms of aboveground weight, 37.75% in terms of underground weight, and 33.97% in terms of aboveground dry weight. This study highlights the critical role of Paenibacillus in tobacco seeds in the suppression of BWD, which may result from its antagonistic and growth-promoting properties.DiscussionThe results of this study revealed differences in the structural characteristics of endophytic bacterial communities between resistant and susceptible tobacco varieties, with groups such as Paenibacillus potentially playing significant roles in resisting BWD. These findings highlight the superiority of seed endophytic microorganisms. In the context of declining plant disease resistance and the spread of bacterial wilt, core endophytic microorganisms in seeds may emerge as a viable option for enhancing the productivity of agricultural ecosystems.

Deficit Irrigation and an IoT-Based System for Improving Yield and Water Use Efficiency of Winter Wheat Grown Under Semi-Arid Conditions

In the context of water restriction, the adoption of innovative technology and water saving strategies is crucial to sustainable agriculture production. Thus, we sought to emphasize the contribution of precision irrigation based on Internet of Things (IoT) technology and smart sensors for optimizing irrigation water use. The effects of different drip irrigation regimes on total dry matter (TDM), grain yield (GY) and water use efficiency (WUE) of winter wheat grown on clay-loam soil under semi-arid conditions of Tunisia have been assessed for three consecutive growing seasons. The trial included fully irrigated (FI) treatment (100% of crop evapotranspiration (ETc)), two deficit irrigation treatments (DI1, DI2 corresponding to 75 and 60% of ETc, respectively) and rainfed treatment DI3, replicated three each. The results showed that TDM and GY increase with increasing irrigation amount. At harvest, the highest TDM and GY values were recorded under FI and DI1. Reducing irrigation amount by 40% (DI2) resulted in a significant grain yield reduction, quantified as 52.7, 45.7, 30.4%, respectively, for the three cropping seasons. Across all growing seasons and treatments, WUETDM values ranged between 4.11 and 6.32 Kg m−3. The highest values were achieved under rainfed treatment. However, no significant difference was observed between irrigated treatments, in particular, during 2022–2023 and 2023–2024. In terms of WUEGY, no significant difference was observed between the FI and DI1 treatments, while significant reductions were registered under DI2 and DI3. The adoption of deficit irrigation at 75% ETc based on smart tensiometers can be used as an effective strategy to optimize water use in winter wheat without compromising yield.

Effect of Hydrolysate Derived from Subcritical Seawater Treatment of Buckwheat Waste on the Growth of Lettuce (Lactuca sativa L.)

This study explores the effects of a subcritical seawater treatment (SST) on buckwheat waste (BW), and the use of the hydrolysate as a liquid fertilizer to improve the growth of lettuce (Lactuca sativa L.). Three temperature treatments (110 °C, 170 °C, 230 °C) were used for the SST, and the ionic composition in the seawater achieved the depolymerization and degradation of BW. The X-ray diffraction of the residual solids showed that the structure of BW was destroyed. Compared with seawater, the hydrolysate contained higher amounts of elements beneficial to plant growth, such as N, P, K, and organic compounds such as phenolics and sugars, as a result of the degradation of BW caused by the SST. The hydrolysate was tested as a liquid fertilizer (treatments H110°C, H170°C, H230°C) to irrigate lettuce. The content of proteins, phenolics, and chlorophyll, as well as the weight of the lettuce in the H110°C and H170°C treatments, were significantly higher than those in the seawater and the H230°C irrigation treatments (p < 0.05). The hydrolysate from the SST of BW, being rich in various organic and inorganic nutrients, can act as a liquid fertilizer that promotes the growth of lettuce, whereas hydrolysate from higher SST temperatures might inhibit the growth of lettuce, because of the excessive total nitrogen and organic acid.

Deficit irrigation differentially modulates rhizosphere microbial community and metabolites of two potato genotypes differing in drought tolerance.

Beneficial interactions between plant root exudates and the rhizosphere microbial community can alleviate the adverse effects of environmental stress on crop yields, but these interactions remain poorly understood in potato growing in drying soil. We investigated the responses of rhizosphere soil microorganisms and metabolites, and biochemical and physiological responses of two potato genotypes with contrasting drought tolerance (drought tolerant 'C93' and drought sensitive 'Favorita'), to two different irrigation treatments imposing contrasting soil water availability in the field. Deficit irrigation altered rhizosphere soil bacterial communities and metabolites of C93 more than Favorita. While the abundance of Nitrosospira and Nitrobacter belonging to the Proteobacteria increased in C93, in Favorita the Streptomyces and Nocardioides belonging to the Actinobacteria increased. These microbial changes were significantly correlated with rhizosphere organic acid concentrations, with 3-phenyllactic acid increasing in C93, and citric acid increasing in Favorita. Although deficit irrigation restricted shoot growth of C93 at the tuber initiation stage (unlike Favorita), its specific root length was 41% greater than Favorita irrespective of irrigation treatment. Deficit irrigation significantly increased foliar chlorophyll and proline accumulation of both genotypes, with the latter 28% higher in Favorita. Independent of irrigation treatment, yield of the more vigorous C93 (producing 22 and 89% more shoot biomass under deficit and full irrigation respectively) was 84% higher than Favorita. It was concluded that different potato genotypes selectively recruit beneficial microorganisms by secreting different organic acids to alleviate the adverse effects of deficit irrigation.

SCHEDULED FOG IRIGATION SYSTEM USING ARDUINO UNO AND RTC (REAL-TIME CLOCK) ON FERTILIZATION OF MUSTARD PLANT (Brassica juncea L.)

The watering of seedings can be done automatically by leveraging the development and advancement of technology, one of which is by utilizing a microcontroller that can be programmed to do watering according to the preferred time. This research aims to design and implement a scheduled fog irrigation system using the Arduino UNO microcontroller and utilizing the RTC (real-time clock) component in the mustard green seeding. In this research, the fog irrigation system is applied to green cabbage by optimizing the Arduino Uno microcontroller, which is used to design electronic circuits to automate the control of watering fog irrigation. Through this system, it is expected that plant watering can be done on time and the plant's water needs can be fulfilled. This research uses the experimental method or experiments with direct observation in the field through several stages, including preparing, designing, and making irrigation installations, constructing a series of scheduled fog irrigation systems, making scheduled irrigation program languages, calibrating RTCs, and working on scheduled fog irrigation systems. The research parameters include water use efficiency and the operation of the scheduled fog irrigation system. The observation parameters were water discharge (mL/min), water use efficiency (%), plant height (cm), number of leaves (strands), and performance of the scheduled fog irrigation system. Three treatments were applied in this study: first-time watering, second times watering, and third times watering. The scheduled fog irrigation system ran well during the research and aligned with the plan. In testing, the fog irrigation system has a water use efficiency of 75.86%, and in the treatment of fog irrigation, three times a day has the highest value of height and number of leaves with an average height of 3.72 cm and an average number of leaves 2.77 strands.

Non-destructive Detection of Growth and Quality in Basil Seedlings Grown in a Plant Factory

Background and objective: Basil is one of the high-value crops cultivated in plant factories. The production of uniform and healthy seedlings has a direct impact on the yield and quality of the final harvest. The objectives of this study were; (1) to ascertain whether non-destructive detecting parameters [projected canopy area (PCA) and vegetation indices (VIs)] could predict changes in growth and quality of basil seedlings, and (2) to determine the feasibility of grading basil seedlings based on PCA to establish a baseline for stable yields after transplanting.Methods: Basil seedlings were grown in 2- and 3-day irrigation cycles for 25 days after sowing, and the growth parameters and image analysis parameters using a multispectral camera were examined at regular intervals. The correlations between growth parameters and PCA/VIs were investigated to detect growth and quality of basil seedlings. At the time of transplanting, the basil seedlings were classified into grades A-D based on their PCA values, and the growth and yield after transplanting of basil seedlings in each grade were evaluated.Results: The basil seedlings in the 3-day irrigation treatment showed higher growth, and the correlation between the PCA values and the leaf area and fresh weight resulted in a coefficient of determination greater than 0.93. Among the VIs, the VARI, GI, and NGRDI were correlated with the growth and quality with coefficients of determination greater than 0.6. And, the growth and yield after transplanting were dependent on the seedling grade based on PCA values at the time of transplanting.Conclusion: This study confirmed that it is possible to predict the growth and quality of basil seedlings using non-destructive image analysis, and that the grading criteria for basil seedlings that can be expected to produce stable yields after transplanting can be determined using image analysis.

Integrated Wastewater Treatment Technology: Efficiency of Lime and Eichhornia crassipes for Agricultural Irrigation

Introduction: wastewater treatment for irrigation is a pressing challenge in rural areas, especially in communities where agriculture depends on contaminated water sources. This study focused on developing a low-cost, sustainable technology tailored to the needs of vulnerable populations.Methods: the efficiency of a combined treatment using lime and water hyacinth (Eichhornia crassipes) was evaluated in Joa, Ecuador. A completely randomized experimental design was employed to assess changes in key physicochemical parameters, including electrical conductivity, hardness, pH, nitrates, and sulfates, before and after the treatments.Results: water hyacinth reduced water hardness significantly, from 218 mg/L to 154 mg/L of CaCO₃, while lime controlled pH, maintaining it near neutral (7,4) with precise dosing. Despite these improvements, the combination showed limitations in reducing nitrates and sulfates to meet local regulatory standards. Nevertheless, the treatments enhanced overall water quality, making it more suitable for agricultural purposes.Conclusions: the combined use of lime and water hyacinth represents a feasible, eco-friendly solution for treating agricultural wastewater in resource-constrained settings. While effective in improving water quality, further studies are needed to optimize the system, explore scalability, and evaluate its long-term impact on soil and crop productivity

Optimized Drip-Fertigation Levels for Improved Water Productivity and Profitability of Capsicum Cultivation under Polyhouse in Himachal Pradesh, India

In this study, experiments were conducted to evaluate the efficacy of varying drip- fertigation levels in terms of soil moisture distribution, soil water stock, yield and water productivity of capsicum (Capsicum annum L.) cultivation under polyhouse. The study comprised two levels of drip irrigation (I0.4 and I0.8 corresponding to 40% and 80% of cumulative pan evaporation, respectively), and four fertigation levels (F50, F100, F150 and F200 representing 50%, 100%, 150% and 200% of the recommended dose of fertilizer, respectively) alongside farmers’ practice and a recommended practice. Initial averaged discharge of 2.39 L h-1 and a uniformity coefficient averaging 99%, indicated excellent moisture distribution. Soil moisture distribution determined at different intervals, indicated saving of water to the tune of 40%-60% in I0.4 as compared to I0.8 and I1.0 with all drip irrigation treatments exhibiting minimal depletion across soil depths. Yield assessments indicated that increasing drip irrigation level from I0.4 to I0.8 and fertigation from F50 to F200 increased the marketable yield significantly (p<0.05). The significantly higher water use efficiency (13.94 g m-2 mm-1) was recorded under I0.4 irrigation level, indicating the challenge of achieving both higher water use efficiency and higher yield at the same time. Fertilizer expense efficiency(157.90 g g-1) was significantly higher with I0.8F50, underscoring the benefits of fertigation. Economic analysis showed that treatment I0.8F200 yielded the highest gross returns (228.15 Rs. m-2) and benefit-cost ratio (5.86) emphasizing the economic viability of capsicum cultivation under optimized irrigation and fertigation levels.

The Effect of Irrigation on the Yield and Soybean (Glycine max L. Merr.) seed Germination in the Three Climatically Varying Years

The paper presents the results of a three-year investigation of the effect of irrigation on the germination and yield of soybeans in three climatically different years in the conditions of eastern Croatia. The experiment was conducted with four soybean varieties (Lucija, Tena, Ika, and Vita) of different maturity groups and in different irrigation treatments (control: natural conditions, rational: 60–100% soil-water retention capacity (SWRC), and abundant irrigation: 80–100% SWRC). An analysis of variance revealed a statistically significant effect of irrigation on the yield throug-hout all three study years. The variety selection affected the yield in 2013 and 2014, while it did not manifest a statistical significance in 2015. The effect of irrigation on seed germination was exerted only in 2015, and an interaction between the irri-gation and soybean variety was not observed in any of the study years. According to the results of the LSD0.05 test, statistically significant differences were observed between the irrigation methods, whereby the t largest statistical difference in. seed germination was achieved with abundant irrigation (LSD0.05 = 1.2039). A correlati-on analysis between the yield and germination produced a statistically significant positive correlation, which was weaker in 2013 and 2014, it was more pronounced in 2015 (r = 0.427*).

Energy Assessment in Rabi Sunflower under Varying Drip Irrigation Regimes and Fertigation Levels

Efficient Irrigation and Nutrient Management Strategies are Important for Sustainability of Agriculture. In order to elucidate the above hypothesis, an on-farm experiment was carried out at Water Technology Centre, PJTSAU, Hyderabad to study the effect of different combinations of drip irrigation regimes and fertigation levels on energy dynamics under Rabi sunflower. The experimental design was split-plot design and contained three replications for DRSH-1 sunflower variety. Three treatments of drip irrigation were compared as main plots (0.8 Epan, 1.0 Epan and 1.2 Epan base values of the Epan pan) and four levels of fertigation at the sub-plots (60%, 80%, 100% and 120% of the recommended dose). 75:90:30 kg NPK ha-1 was set for the fertilizer recommendation. Energy parameters: energy output, energy efficiency, net energy gain, energy profit, and energy intensity were assessed across treatment combinations. The findings indicated that peak energy consumption transpired under settings integrating 1.2 Epan irrigation with a 120% recommended dosage of N and K₂O fertigation. The optimal irrigation level was 1.0 Epan, which produced enhanced outcomes in energy output (102.6 GJ ha-1), use efficiency (5.02), and nett energy gains (90.1 GJ ha-1) relative to lower irrigation levels. The application of the full prescribed dose in fertigation treatments proved to be excellent, exhibiting exceptional performance across all energy metrics: output (105.6 GJ ha-1), usage efficiency (8.1), nett energy (92.5 GJ ha-1), profitability (0.223), and intensiveness (0.0022). Statistical study revealed no significant interaction between irrigation and fertigation treatments, indicating that these parameters independently affect energy efficiency indicators.

Potential Effects on the Quinoa Cultivation Yield Based on Different Hydric Scenarios of the Chilean Altiplano

This study evaluates the impact of different irrigation scenarios on the yield of quinoa (Chenopodium quinoa) in the Chilean Altiplano. The research was conducted in Ancovinto, Tarapacá, Chile, using “Pandela” quinoa seeds. Four irrigation treatments were implemented: rainfed (T0) and irrigation at 100% ETc (T1), 66% ETc (T2), and 33% ETc (T3). Various climatic variables, the soil moisture content, and agromorphological parameters were measured. The results indicated that rainfed conditions (T0) led to higher dry matter production in roots, stems, leaves, and panicles at the end of the growth cycle compared to irrigated treatments. The Leaf Area Index (LAI) was also higher in rainfed conditions during the flowering stage, demonstrating the crop’s adaptability to adverse water conditions. Additionally, the ability of quinoa plants under rainfed conditions to tolerate frost during critical growth stages was a key factor in their superior performance, contributing to a higher grain yield and harvest indices. Plants under rainfed conditions reached greater heights and showed higher harvest indices (HI) and grain yield than those under irrigation. The Water Use Efficiency (WUE) was significantly higher in rainfed conditions, suggesting more effective water utilization under water scarcity. This research represents a one-year study that provides orientations for future research, considering the interannual variability of precipitation in the region. The results obtained show that quinoa plants under traditional management (rainfed) exhibited the best response in the measured growth, development, and production variables, leading to higher production and harvest rates. Additionally, there was greater efficiency in water use, equivalent to 15.87 and 12.7 times that of the 100% and 33% ETc treatments, respectively. These findings highlight quinoa’s remarkable adaptability to harsh hydric conditions and the efficiency of traditional rainfed farming practices in the Altiplano.

Assessing the Impact of Irrigation and Biostimulants on the Yield and Quality Characteristics of Two Different St. John's Wort Cultivars in Their Second Growing Season.

The perennial species Hypericum perforatum, commonly known as St. John's Wort, is well regarded for its medicinal attributes, particularly its strong anti-inflammatory and antidepressant effects. Hypericum perforatum L., commonly known as balsam, is extensively employed in both traditional and contemporary medicine due to its biological properties, although the plant's medicine distribution is limited to Europe and Asia. This study pioneers the investigation of Hypericum perforatum cultivation in a Mediterranean country, specifically Greece, focusing on the effects of irrigation and biostimulants of two distinct genotypes on quantitative (height, drug yield, essential oil yield) and qualitative (essential oil content and composition) characteristics. A field trial was conducted at the experimental farm of the Agrotechnology Department at the University of Thessaly, located in the Larissa region. This study investigated various testing varieties under different irrigation levels and biostimulant applications. The results underscore the importance of customized irrigation and biostimulant strategies in improving yield and quality during the second growing season, establishing a foundation for sustainable agricultural progress. Notably, irrigated treatments significantly increased plant height, dry biomass yield, and essential oil production per hectare. Specifically, the essential oil yields for irrigated treatments were nearly double those of rainfed treatments, with 219 kg/ha for rainfed and 407 kg/ha for irrigated. The genotype played a crucial role in influencing production potential, height, flowering, and essential oil composition, with one variety demonstrating biennial blooming and modified essential oil compounds. While irrigation positively impacted yield, it also reduced certain essential oil compounds while increasing β-pinene content. The effects of biostimulants varied based on their composition, with some enhancing and others diminishing essential oil content. Notably, the biostimulant containing algae with auxin and cytokinin (B2) proved to be the most effective in improving the therapeutic profile. This study offers valuable insights into the cultivation of H. perforatum in a Mediterranean climate, highlighting the necessity for ongoing research into native populations, irrigation levels, biostimulants, fertilization, and other factors that affect crop yield and quality characteristics.

Yield Responses to Total Water Input from Irrigation and Rainfall in Six Wheat Cultivars Under Different Climatic Zones in Egypt

In Egypt, wheat is the most consumed cereal grain, and its availability and affordability are important for social stability. Irrigation plays a vital role in wheat cultivation, despite intense competition for water resources from the River Nile across various societal sectors. To explore how grain and above-ground biomass yields respond to total seasonal water input from sowing to maturity in six bread wheat cultivars, eight field irrigation experiments were performed at four locations representative of three agro-climatic zones in two consecutive cropping seasons. A three-replicate strip-plot design was used with cultivars nested within the main plots featuring five irrigation treatments, ranging from six to two applications. Overall, irrigation treatment significantly affected nine agronomic traits. Compared with the six irrigation applications treatment (T1), the two irrigation applications treatment (T5) decreased the times to heading and maturity by 6.6 (7.3%) and 8.6 (6.3%) days, respectively. Similarly, T5 reduced the plant height by 14.9 cm (14.3%), flag leaf area by 12.0 cm2 (27.2%), number of spikes per square metre by 77.7 (20.1%), number of kernels per spike by 13.9 (25.2%) and thousand grain weight by 10.0 g (19.6%). T5 also decreased the overall mean grain yield and above-ground biomass yield by 2834.9 (32.0%) and 7910.4 (32.86%) kg/ha, respectively. The grain yield and above-ground biomass production were consistently greater for all six cultivars at Al Mataenah and Sids than at Nubaria and Ismailia in the two cropping seasons. All six cultivars showed significantly greater responses to total seasonal water input for the grain yield and above-ground biomass at Al Mataenah and Ismailia. These results emphasise the necessity for choosing regions with favourable soil and climatic conditions to grow wheat cultivars that respond better to irrigation to enhance the large-scale production of wheat in Egypt. The grain and above-ground biomass yields were mostly linearly and positively associated with the total seasonal water input for all six cultivars at all four locations. This suggests that maintaining the current irrigation schedule of six irrigations is valid and should be practised to maximise productivity, particularly in areas similar to the three representative agro-climatic zones in Egypt.

Effects of Cyclic Aeration Subsurface Drip Irrigation on Greenhouse Tomato Quality and Water and Fertilizer Use Efficiency.

Tomato (Jinglu 6335) was selected for assessing the impact of varying fertilizer (F:N-P2O5-K2O) and aeration rates on crop quality, as well as water and fertilizer utilization efficiency during the cyclic aeration subsurface drip irrigation process. Four aeration treatments (O1, O2, O3, and S, representing aeration ratios of 16.25%, 14.58%, 11.79%, and non-aerated treatment, respectively) and three fertilizer applications (F1: 240-120-150 kg/hm2, F2: 180-90-112.5 kg/hm2, F3: 120-60-75 kg/hm2) were compared in a total of 12 treatments in this study. This study revealed that cyclic aerated drip irrigation improved the fruit quality. The aerated treatment resulted in increased accumulation of nitrogen, phosphorus, and potassium, with the level of aeration positively correlating with the increase in nutrient accumulation, reaching the highest values in the high aeration irrigation treatment. The highest nitrogen, phosphorus, potassium, and water use efficiency occurred under the medium fertilizer with high aeration treatment. The maximum partial productivity of the fertilizer occurred under the low fertilizer with high aeration treatment, while the minimum occurred in the high fertilizer with non-aerated treatment. Taking all factors into consideration, the high-aeration and medium-fertilizer treatment was the most effective combination for greenhouse tomatoes under the conditions in this experiment.

Water use efficiency and grain yield of water stressed-field grown triticale as affected by combined application of biochar and biological fertilizer

Water stress poses a significant constraint on crop productivity in arid regions. A 2-year field experiment was conducted using a split-factorial layout within a randomized complete block (RCB) design to determine whether the combination of Azospirillum brasilense and Pseudomonas fluorescens (plant growth-promoting rhizobacteria [PGPRs]) with organic matter (OM) can mitigate the negative impacts of water stress on the grain yield of triticale (×Triticosecale Wittmack), as well as on water use efficiency for grain (WUEg) and biomass (WUEb). Irrigation treatments, including full irrigation (IRN) and post-milking deficit irrigation (IRD), were assigned to the main plots. Subplots were allocated to different OM sources (no OM, wheat residue, and its biochar) and nitrogen-phosphorus (N-P) sources, viz: chemical N-P fertilizer and integrated N-P fertilizer (50% chemical N-P fertilizer combined with PGPRs). Results indicated that IRD led to a significant decrease in grain yield (60.1%) and, ultimately, WUEg (43.4%) without OM application. However, using biochar resulted in the lowest reductions in these traits (41.1% and 14.6%, respectively) compared to the other OM treatments. The application of integrated N-P fertilizer resulted in an increase in grain yield, WUEg, and WUEb, across all types of OM compared to chemical N-P fertilizer. Notably, the most substantial improvements were observed with the application of biochar, which enhanced grain yield, WUEg, and WUEb by 24.5%, 27.7%, and 18.6%, respectively. Additionally, the application of integrated N-P fertilizer mitigated the decline in average grain weight, a crucial factor influencing the grain yield of triticale, under post-milking water stress conditions. Finally, integrated N-P fertilizer in conjunction with biochar is recommended for arid regions facing irrigation water restrictions during the grain-filling stage of triticale.

Effects of Irrigation Methods on Growth and Water Productivity in Bell Pepper Cultivation in Northern South Korea

Although the bell pepper (Capsicum annuum L.) is sensitive to water stress, little information is available on proper irrigation management methods for bell pepper cultivation in the northern South Korean climate. We compared the effects of different irrigation methods on crop growth and water productivity in two bell pepper varieties (Maldonado and Nagano) at different irrigation durations (ending 3 h before sunset and ending 4 h before sunset) and irrigation quantities (placing two, three, and four drippers capable of irrigating at 2 L·h−1) over approximately 280 days by performing in-depth analysis of various growth indicators. The plant height of Maldonado increased as the irrigation amount increased in all irrigation treatments of T1 and T2. In Nagano, there was no significant difference in plant height between D3 and D4. Overall, the irrigation treatments produced a higher difference in yield in Maldonado plants than in Nagano plants. WP tended to increase inversely to reduction in irrigation quantity in Groups 1 (May–June) and 4 (November–December) of both varieties, and response to irrigation stop time varied among the varieties. We inferred that the optimal irrigation method for bell pepper cultivation in northern South Korea is to supply irrigation at the D3 level and adjust the irrigation end time according to the variety and crop strength.

Impact of Irrigation and Fertigation Schedules on Physical and Biochemical Properties of Apple Under High-Density Plantation

ABSTRACT Over the 2-year period of study (2019–2020), the impact of different irrigation and fertigation schedules on the physical and biochemical properties of apple under high-density plantation was investigated. The quality of fruits is considerably influenced by irrigation and fertigation. Drip fertigation levels unveiled significant effect on fruit length (65.43 mm), fruit breadth (72.32 mm), and fruit weight (187.53 g). The application of 100% ETc with 100% AD (NPK) during fertigation enhanced both fruit size and weight. Under uniform application of water, photosynthesis increased, which improved the assimilate partitioning. Growth hormones, including cytokinins, gibberellins, and auxins, are generated at optimal and uniform nutrient distribution, which promotes nutrients uptake and assimilates water translocation, resulting in increased fruit size and weight. Drip irrigation and fertigation treatments produced fruits with better color. A higher dose of NPK applied via drip fertigation system produced higher levels of anthocyanin and ascorbic acid content in fruits over conventional approaches. Merging new orchard designs with a high-coloring strain of an apple cultivar and more efficient irrigation and fertigation systems results in higher productivity with better fruit quality and less water consumption.

Effect of normal irrigation and water stress conditions on some characteristics of cotton in Toshka region -Egypt

Irrigation, water stress, planting dates and planting distances are crucial for obtaining desirable fiber properties for Egyptian cotton, especially under climate change. Two field experiments were carried out at the Water Studies and Research Complex (WSRC) station, National Water Research Center, Toshka, Egypt in the 2021 and 2022 growing seasons, to evaluate some morphological traits and fiber quality properties of the Egyptian cotton cultivar Giza 95 under three planting dates (january, february, and march) and 6 planting distances (10, 15, 20, 25, 30, and 35 cm among plants), comparing them with two irrigation treatments (100% A.W. and 80 % A.W.). The main effects of irrigation treatments, planting dates, and planting distances in both seasons were found to be significant (P<0.05 or 0.01) for most morphological and fiber quality properties under study. Also, the first-order interactions of irrigation treatments with planting dates, and planting distances have significant effects (P<0.05 or 0.01) on most studied traits in both seasons. In both seasons, positive effects were observed for the number of fruiting branches, plant height, and fiber fineness traits with irrigation treatment (80 % A.W.) and other fiber quality properties with irrigation treatment (100% A.W.). When compared to other planting dates in both seasons, the February planting date produced the best values for the majority of the analyzed traits, however, the January planting date produced a higher number of fruiting branches. Wider plant spacing produced the best results for fiber quality properties, whereas 10 cm spacing between plants resulted in more fruiting branches. Based on mean performances and principle component analysis, the February planting date with wider plant spacing under irrigation treatment (80% A.W) may be a better method to improve fiber quality properties in the experimental region under study. Additionally, these data will help develop plans for better agricultural practices and enhancing Egyptian cotton's fiber quality

Effect of Irrigation Methods and Fertilizer Application on Growth and Yield Parameters, Yield, Economics and Water Use Efficiency in Groundnut

The present investigation was carried out at Agricultural Research Station, Bhavanisagar, Erode district of Tamil Nadu to study the effect of irrigation methods and fertilizer application effects on growth and yield parameters, yield, economics and water use efficiency in groundnut. The various irrigation methods followed were I1 – Drip irrigation, I2 – Drip fertigation, I3 – Sub surface drip irrigation, I4 – Sub surface drip fertigation, I5 – Sprinkler irrigation and I6 – Conventional method of irrigation as main plot treatments and the various methods of application of fertilizers were S1 – Absolute control (No fertilizer), S2 – Recommended dose of NPK fertilizers through normal fertilizers / Recommended dose of NPK fertilizers through water soluble fertilizers (According to the irrigation treatment) and S3 - S2 + Vermicompost @ 5 t ha-1 imposed as subplot treatments, and the treatments were replicated thrice. The experiment was laid out in strip plot design in a plot size of 15 M2. Application of recommended dose of fertilizers (25: 50: 75 kg NPK ha-1)along with vermicompost @ 5 t ha-1 with sub surface drip fertigation recorded highest growth [plant height (49.3 cm); number of branches (7.1) and number of leaves (69.2)] and yield attributes [number of pods per plant (38.2)], yield [pod yield (3271 kg ha-1)] high Benefit Cost Ratio (3.03) and water use efficiency (15.16 kg ha-1. mm) as compared to the other treatments in groundnut (var. VRI 3).

Combined Effects of Deficit Irrigation and Biostimulation on Water Productivity in Table Grapes.

Biostimulation and precision irrigation are strategies that increase the sustainability of agriculture, and both have been widely studied in table grapes, but their interaction is a new approach for viticulture. The objective of this field trial was to assess the physiological effects of water deficit on table grapes pretreated for two consecutive years with five different biostimulation programs. Therefore, during the first year, vines were preconditioned with biostimulants composed of microorganisms, seaweed, and plant extracts and compared to an untreated control. During the second year, the same biostimulation treatments were evaluated under two different irrigation schedules: (i) farmer irrigation (FI), according to a farmer's criteria; and (ii) a deficit irrigation program, precision irrigation (PI), in which irrigation water was reduced from the post-veraison period to harvest, setting a threshold for allowable soil water depletion of 10% with respect to field capacity in order to minimize water leaching. The water inputs in the treatments under PI were reduced by 30% with respect to the FI treatment. While the deficit irrigation treatment clearly affected the plant water status indicators, biostimulation enhanced the root colonization by mycorrhizae and showed a trend of increased new root density. The combined effect of biostimulation and PI was shown to be an efficient strategy for optimizing the available resources, promoting the yield precocity.