Crop Water Requirements Research Articles

Understanding trends and gaps in global research of crop evapotranspiration: a bibliometric and thematic review

Estimating crop evapotranspiration (ETc) is crucial for ensuring sustainable and efficient agricultural water management. Although this subject has garnered significant attention from the global scientific community, a comprehensive study encompassing the diversity, trends, and dynamics of research themes is currently lacking. To address this knowledge gap, this review employed a combined bibliometric and thematic approach to analyze bibliographic data from 1872 documents retrieved from the Web of Science™ core collection, spanning the period 1987–2022. The main findings of this review are as follows: (1) the scientific landscape is predominantly shaped by institutions from the USA and China; (2) the journal Agricultural Water Management emerged as the most prolific, with the highest number of publications and total citations; (3) a broad range of topics within ETc research were identified, with a notable emphasis on remote sensing-related subjects; (4) strategic coordination mapping revealed that ETc and reference evapotranspiration (ETo) remains an underdeveloped area of study; (5) climate change and machine learning emerged as key topics of significant scientific concern. The results suggest a need for enhanced institutional collaborations and expanded research investigations, particularly in regions grappling with agricultural water scarcity. Furthermore, research investigations should focus on ETc and ETo to fill existing knowledge gaps and advance both theoretical understanding and practical applications. Future studies should aim to contribute to the understanding of the impacts of climate change on ETc by leveraging machine learning techniques and enhancing our understanding of crop water requirements and their application in irrigation management, while also ensuring continuous updates to the existing body of knowledge to meet future challenges.

Long-Term Forecasting of Crop Water Requirement with BP-RVM Algorithm for Food Security and Harvest Risk Reduction

Long-Term Forecasting of Crop Water Requirement with BP-RVM Algorithm for Food Security and Harvest Risk Reduction

Balancing crop water requirements through supplemental irrigation under rainfed agriculture in a semi-arid environment

Rainfed farming is a dominant agricultural system in Tigray, Ethiopia. However, rainfall is characterized by short duration, intense and erratic subjected to late-onset and early cessation, suggesting a pressing need for Supplemental Irrigation (SI) to fill the crop water demand. Understanding the effects of SI during rainfall late-onset, early cessation, or both, along with their underlying causes, is a critical knowledge gap globally. Although wheat is one of the principal food crops in Tigray, it is subjected to moisture stress during critical growth stages, limiting its potential productivity. Studies specifically related to impacts due to the late-onset of rainfall on wheat are non-existent. Here, we investigated the agrometeorological characteristics of rainfall variability, onset, cessation, and length of the growing season to evaluate the use of SI for balancing the moisture stress in rainfed farming. Meanwhile, using an on-farm experiment, we also evaluated double-season (2017 and 2018) SI application during late-onset (Pre), early cessation (Post), and its combined effects (Pre + Post) on yield and water productivity (WP) of wheat. Yield and WP were significantly (P < 0.05) affected by SI application with higher grain yield (3298 kg/ha) and WP (0.538 kg/m3) obtained from applying Pre + Post. Applying Pre + Post has increased grain yield, biomass, and WP of wheat by 45.6, 27.7, and 21.5% over Rain-fed farming, respectively. Thus, balancing crop water requirements using SI during inadequate rainfall distribution is key for improving WP and wheat production in semi-arid environments. Particularly, the application of SI both during the late-onset and early cessation of rainfall is suggested for greater wheat productivity in semi-arid regions.

Combining deficit irrigation and nutrient amendment enhances the water productivity of tomato (Solanum lycopersicum L.) in the tropics

Water availability for irrigation farming is one of the greatest challenges associated with the increasing spatio-temporal effects of climate change and variability on tomato production, especially in tropical regions. This study was conducted to demonstrate the combined effect of irrigation and nutrient management as a water-saving strategy to maximize nutrient and water productivity in tomato production. The research was conducted in a screen house at the CSIR-Crops Research Institute (CSIR-CRI), Kumasi, Ghana using the split-plot design in the 2020 and 2021 cropping seasons. The main plot consisted of a single full irrigation at 100% recommended crop water requirement and two deficit irrigation levels (75 and 50% of the crop water requirement). The subplots consisted of two nutrient amendments (inorganic fertilizer and organic compost) and a control (without any nutrient amendment). Data from the research was used to parameterize the DSSAT CCROPGRO model to simulate the interactive effect of irrigation and nutrient management on the yield of tomatoes. Plant height and stem girth did not have a specific influence on tomato yield, but the number of branches had a positive effect on tomato yield. The combined use of inorganic fertilizer and full irrigation was found to improve tomato yield up to 7691.4 and 9009.9 kg/ha whereas treatment with no fertilizer application at 50% deficit irrigation recorded the lowest tomato yield of 1423.9 and 1739.2 kg/ha in 2020 and 2021, respectively. For the two deficit irrigations (50 and 75% ETc), organic compost produced the highest tomato yield. Deficit irrigation recorded higher crop water productivity (CWP) compared to full irrigation. At 50% deficit irrigation, organic compost recorded the highest CWP of 4.54 kg/m3 in 2020 while inorganic fertilizer recorded the highest CWP of 5.52 kg/m3 in 2021. No fertilizer at full irrigation recorded the lowest CWP of 1.37 and 1.67 kg/m3 in 2020 and 2021, respectively. This study has revealed that deficit irrigation with organic compost has the same effect on yield and water productivity as full irrigation with inorganic fertilizer. The strong agreement observed between the measured and simulated yields under the different irrigation and nutrient management shows that the DSSAT CROPGRO tomato model can be used to simulate tomato fruit yield under future climate scenarios. However, the general overestimation of the measured tomato yield shows the limitations of the model to simulate the real-world complexity of cropping systems under controlled conditions. This calls for more research into crop system modeling in controlled environment agriculture.

Impact of guar gum‐based hydrogel on yield and economics for sugarcane crops

AbstractAccording to the current scenario, water crises are booming at a higher rate globally, affecting different demands such as agricultural, domestic, industrial, and so forth. Ultimately, such a water crisis may affect food safety. We have developed guar gum (GG)‐based hydrogel to help solve this issue with a water‐saving objective. This paper presents the application performance of newly developed GG‐based hydrogel on sugarcane crop growth, yield, and its economics. The crop water requirement and irrigation scheduling are also obtained using the CROPWAT model. Comparing different irrigation practices indicates that six irrigations can be saved by applying the CROPWAT optimization model, and up to three irrigations can be saved by applying different dosages of GG‐based hydrogel against the conventional method. Moreover, a set dosage application of 2.5 and 5 kg ha−1 of GG‐based hydrogel has elevated the cane height up to 8.67% and 10.02%, respectively. Furthermore, a considerable increment of 5.5% and 8% was found in the crop yield. In addition, the average soil moisture was found to be 10.50% and 17% higher over the field without hydrogel by using an indigenously developed Internet of Things–based SS316L soil moisture sensor. Applying GG‐based hydrogel (2.5 and 5 kg ha−1) saves the number of irrigations by two and three times, respectively. When it comes to the economy, the benefit–cost ratio for 2.5 and 5 kg ha−1 hydrogel dosages was found to be 2.64 and 2.09, respectively. Thus, GG‐based hydrogel shows substantial promise as a useful agricultural product for water‐saving purposes.

Water Requirement of Major Tuber Crops: A Review

One of the most crucial input required for the growth of crops is water. It is required by plants in enormous amounts and continually throughout their lifecycle. It has a significant impact on plant processes like photosynthesis, respiration, cell division, absorption, translocation, use of mineral nutrients and agriculture operations like irrigation, land husbandry, crop production, medium for spraying chemicals etc. But the future water supply is questionable due to climate change and related problems like rise in temperature. This lead to change in precipitation patterns and the entire water cycle are thrown off balance. Therefore, in the current environment, the development of water-saving agriculture is essential. As tuber crops are known for their high water use efficiency, it is having big part in water saving agriculture. Tuber crops are major sources of carbohydrates, thus play a key role in food safety. The starchy root of tuber crops can be used for various purposes like food, livestock feed, raw material in industry mainly for starch production etc. As most of the tuber crops are compatible with the farming systems, resistant to drought and withstand aberrant rainfall conditions, farmers follows rainfed cultivation of tuber crops. Anyhow water deficit stress occurring during the critical phases would adversely affect the ultimate performance of tuber crops and judicious use of water will result maximum yield. This review paper aims to know the water requirement of major tuber crops (Potato, Cassava, Sweet Potato, Amorphophallus, Taro and Tannia) and influence of water management in their yield potential.

A soil database from Queretaro, Mexico for assessment of crop and irrigation water requirements

Several studies have assessed crop water requirements based on soil properties, but these have been on a small scale or on soils with similar textures. Here, a data base of soil measurements in the field and laboratory from sites across Irrigation District 023, San Juan del Rio, Queretaro, Mexico was sampled, collected, analyzed, and integrated. The data base, named, NaneSoil, contains information on 900 samples obtained from irrigated plots. NaneSoil cover 10 of the 12 textural classes with the following information: sand, silt, clay contents, bulk density, saturated volumetric water content, field capacity, permanent wilting point and saturated hydraulic conductivity. The aim of this work is to provide the scientific community with sufficient information to perform a large number of analyses, for example, development of pedotransfer functions, calculation of water requirements of plants in soils with similar characteristics, modeling of infiltration, optimal irrigation discharge calculation, among others. The dataset also promotes the scientific community to contribute their own measurements to further strengthen the knowledge of flow in the porous medium.

Effect of foliar application of different concentrations of salicylic acid on Washington navel orange trees under water stress

BackgroundA field experiment was performed from 2021 to 2022 on 10-year-old Washington navel orange trees (Citrus sinensis) budded on sour orange rootstock (Citrus aurantium) under sandy loam soil conditions in the region of Belbeis—El Sharkia Governorate, Egypt. This study was carried out to increase water use efficiency, maximize water utilization and determine the most effective treatment of Washington navel orange trees by using different concentrations of salicylic acid (control, 250, 500, and 750 ppm) under some levels of water stress (100, 75 and 50% of estimated crop water requirement).ResultsIn this scenario, the water use efficiency increased with 750 ppm of salicylic acid under 75% of the estimated crop water requirement, which produced 2.27 and 3.09 kg of fruit for each cubic meter of irrigation water in the first and second seasons, respectively. In addition, using salicylic acid treatment with 750 ppm under 75% of the estimated crop water requirement had a high economic return through increasing water unit return, while using less water irrigation amount by 25% at the same time, which reached 9.06 and 12.38 EGP per every cubic meter of irrigation water in the first and the second seasons, respectively.ConclusionIn summary, the data cleared that the irrigation water quantity could reduce by 25% while maintaining the production and the possibility of increasing it by using salicylic acid with the highest concentration. Thus, we recommend applying the treatment of the estimated crop water requirement with 75% combined with salicylic acid 750 ppm to Washington navel orange trees budded on sour orange rootstock to gain a high economic return.

Estimating the Water Footprint of the Four Important Cereal Crops in the Euphrates River Basin, Iraq

The footprint of water (WF) is a clear feature of how much water is used during crops and commodity production and other uses in industry and human use. The current research assessed and discussed the water footprint average of the main 4 crops in the seven Iraqi Euphrates River basin provinces during the 2010–2020 years. The levels of blue and green Water footprint were calculated using the Crop Water Requirement (CWR) option in CROPWAT 8.0 software and the findings were compared to global averages and other studies that looked at the same crops. The average annual usage water footprint (WF) for the provinces of Qadysia, Najaf, Dhi-Qar, Muthanna, Babylon, Anbar, and Karbala over the ten years. The average blue WF was 99.72 % and the green WF of rice was 0.28 % where the total production of WF was 789,281,155 m3/yr. Some provinces like Muthanna produces little and has a higher WF so, rice could be replace it with other crops such as vegetables that are provide most economic benefits and needed less water, and production should be concentrate in lower WF provinces like Qadysia and Najaf, while provinces for Najaf and Babylon has a relatively lower total WF of wheat but Anbar has higher WF and using more water for wheat rather than national averages. So, at these provinces, the wheat could be replace it with crops that are need less than water and provided most economic benefits. provinces for Babylon followed by Anbar have a relatively lower total WF of barley but, Dhi-Qar has a higher WF and uses more water of barley. Provinces of Najaf and Anbar has high WF while the Muthanna has lower WF, the current study is expecte to contribute to national authorities into develop most accurate irrigation water managements policies.

Assessment on Water Footprint of Paddy Cultivation in Kedah

A measurable metric to gauge both the amount of water pollution and water consumption per unit of crop is the water footprint (WF). WF can be used as a thorough indicator of the utilization of freshwater resources. To increase the yield of crops, agriculture, consumed large amount of water. To prevent water shortages, it is crucial to understand how much water is consumed during agriculture. This study’s goal is to estimate the region of Kedah’s water footprint for paddy cultivation in the year 2017. By using CROPWAT 8.0 computer programming, climatic parameters were used for the estimation of water evapotranspiration for blue and green to proceed with the water footprint accounting. The methodological framework followed the crop water requirement (CWR) option based on the water footprint assessment manual. Focusing on the water footprint accounting phase, the blue, green and grey water footprint was calculated. The findings demonstrated that the three forms of water footprints differ significantly from one another. In Kedah, the value of the green water footprint (1201m3/ton) is higher than that of the blue water (130m3/ton) and the grey water (357m3/ton) footprints. 71% of green water footprint indicates that there is enough rainfall to support paddy growth.

Selection of Drought-Tolerant Pasture Species under Varying Soil and Moisture Conditions in Bauchi State, Nigeria

Livestock production is an agricultural system that serves as humanity’s protein and calorie source. Its production is the main economic stay for some people and a complementary source for others. However, land misappropriation and draught constrain the sustainable production of pasture for feeding livestock. Further aggravated by farmer/herder clashes and wetlands extinction. The need for an experiment for the selection of the best pasture species in the Sudan Savannah region that can thrive well under diverse soil textures and moisture status becomes imperative. This trial was conducted in the screen house of Babcock University, objectively to test the performances of Sorghum almum, Andropogon gayanus, Brachiaria mulato and Centrosema pascuorum under Sand, Sandy Clay Loam, and Sandy Loam textures and four water regimes: 100%, 75%, 50%, and 25%. Standard agronomic recommendations were practised throughout the experiment. Data collected included plant height, fresh and dry shoot and root weights, number of leaves, and leaf length. Data generated were analyzed using ANOVA. According to the results, Sandy Loam soil (Soil type from Gamawa) was the best for supporting all the pasture species, followed by Sandy Clay Loam (Soil type from Zaki). S. almum outperformed other pasture species significantly irrespective of soil textural type and water stress level treatments, followed by B. mulato. For water levels; 100% and 75% had the most promising biomass outcome. Based on the results, a 75% water regime which represents 25% deficit of the actual crop water requirement is recommended for the production of the tested pastures in the area.

Water footprint of paddy cultivation under controlled runoff conditions: A case study in Kurunagala district, Sri Lanka

Paddy cultivation is the largest global consumer of water, and it also significantly contributes to water pollution. Investigating the water footprint of paddy agriculture can provide insights into how pollutants affect the ecosystem. This study aimed to quantify the total water footprint for paddy grown in Sri Lanka's Low Country Intermediate Zone under supplementary irrigation. A lysimeter study was carried out to determine the amount of leached nutrients below the root zone. The experimental design was a Complete Randomized Block Design (CRBD) with two factors (cropping season and gradient) and two levels (Yala and Maha; upper and lower). The green and blue water footprints for both sites were estimated using the CROPWAT 8.0 model by crop water requirement option. The results revealed that the loss of NO3-N through leaching accounted for 8.61 ± 1.84 kg/ha (8%), and the leaching losses of PO43-- P were 0.49 ± 0.1 kg/ha (2%) under controlled runoff conditions during the experimental period. The nitrogen fertilizer-induced grey water footprint (WFgrey) for one tonne of rice produced was 193 ± 27 m3/t, and the phosphorous fertilizer-induced WFgrey was 61 ± 7 m3/t. The study identified nitrate as the critical element for water pollution. The estimated total water footprint (WFtotal), which was the sum of green, blue, and grey water footprint, was 1409 ± 95 m3/t under controlled runoff conditions, while the global average value is 1325 m3/t. The estimated value is about 6% higher than the global average value. Therefore, these findings demonstrate the need for further research.

Water Requirements and Comprehensive Benefit Evaluation of Diversified Crop Rotations in the Huang-Huai Plain

An intensified farming system can significantly increase crop productivity but can also cause major groundwater overdraft for irrigation and the loss of crop diversity. It is imperative to develop alternative crop rotations beyond the simplified conventional winter wheat–summer maize (W–M) rotation for alleviating the groundwater over-extraction in China’s Huang-Huai Plain. This study systematically quantified crop water requirement (ETc) and irrigation water requirement (ETaw) of eight crops from 2013 to 2018 based on the SIMETAW model applied to the Shangqiu area in the Huang-Huai Plain. Fourteen crop rotations (CI (i.e., crop harvests per rotation cycle year) 1.5 or 2) were constructed based on the ROTAT model. Results showed that compared to W–M rotation, the alternative rotations (CI = 1.5) significantly reduced the annual ETc in wet, normal, and dry years by 9–21%. Replacing winter wheat in the double cropping system did not significantly decrease annual ETc. Wheat–soybean rotation had similar annual ETc and ETaw accompanied by higher economic output and equivalent yield about 1.2 times, with 9% more protein output than the W–M rotation. There were eight crop rotations having greater comprehensive evaluation index (CEI) than W–M rotation by Entropy-TOPSIS when considering 10 indicators including water requirements, yield, economic benefits, water use efficiency, energy, and nutritional values. Spring potato–summer soybean had the highest CEI of 0.627. Sweet potato and potato showed advantages when included in rotations by increasing yield. “Wheat–soybean”-based rotations (CI = 1.5) also performed well in profitability and protein output. Replacing summer maize with soybean is promising for profitability and nutrition output without increasing irrigation requirements. Therefore, decreasing the cropping index, or involving soybean or sweet potato in rotations can be a useful way to improve sustainable land use, save water, and ensure food products in this water stressed region.

Modeling Soil Hydraulic Properties Using Dynamic Variability of Soil Pore Size Distribution

The knowledge of temporal variability of soil hydraulic properties (SHPs) in agricultural fields can help in reliable assessment of crop water requirement, thus improving irrigation water usage efficiency. The Fokker–Planck equation (FPE) and its modified forms are popularly used to describe temporal variation in SHPs. These models consider statistical description of soil pore size distribution (PSD) as a probability density function to estimate SHP evolution with time. In this study, we compare four different models to describe the temporal evolution of PSD and SHPs for multiple datasets across the world with different soil types, tillage conditions and crop cover. Further, field experiments were carried out at an experimental agricultural field at IIT Kanpur for rice crops, and the performance of these models was also evaluated for Indian conditions. It is observed that existing models have low accuracy for small pore radii values, and the prediction ability of these models is more affected by soil type rather than tillage conditions. More observations can improve the performance of FPE-based numerical and analytical models. The POWER Model is the least accurate because of its inherent power law assumption of PSD, which results in incorrect values for low pore radii. The FPE analytical model can be reliably used for predicting PSD and SHP evolution at most of the field sites.

Proximal Soil Moisture Sensing for Real-Time Water Delivery Control: Exploratory Study over a Potato Farm

New sensing technologies are at the cusp of providing state-of-the-art infrastructure to precisely monitor crop water requirements spatially so as to optimize irrigation scheduling and agricultural productivity. This project aimed to develop a new smart irrigation system that uses an L-band radiometer in conjunction with an irrigation boom, allowing for a precision water delivery system using derived high-resolution soil moisture information. A potato farm was selected due to its sensitivity to water and an existing irrigation system where the radiometer could be mounted. A field experiment was conducted to capture the soil moisture variation across the farm using the radiometer. A greenhouse trial was also conducted to mimic the actual growth of potatoes by controlling the soil moisture and exploring the impact on their growth. It was found that 0.3 cm3/cm3 was the optimal moisture level in terms of productivity. Moreover, it was demonstrated that on-farm soil moisture maps could be generated with an RMSE of 0.044 cm3/cm3. It is anticipated that through such technology, a real-time watering map will be generated, which will then be passed to the irrigation software to adjust the rate of each nozzle to meet the requirements without under- or over-watering.

Climate resilience of dry season cereals in India

India is the world’s second largest producer of wheat, with more than 40% increase in production since 2000. Increasing temperatures raise concerns about wheat’s sensitivity to heat. Traditionally-grown sorghum is an alternative rabi (winter season) cereal, but area under sorghum production has declined more than 20% since 2000. We examine sensitivity of wheat and sorghum yields to historical temperature and compare water requirements in districts where both cereals are cultivated. Wheat yields are sensitive to increases in maximum daily temperature in multiple stages of the growing season, while sorghum does not display the same sensitivity. Crop water requirements (mm) are 1.4 times greater for wheat than sorghum, mainly due to extension of its growing season into summer. However, water footprints (m3 per ton) are approximately 15% less for wheat due to its higher yields. Sensitivity to future climate projections, without changes in management, suggests 5% decline in wheat yields and 12% increase in water footprints by 2040, compared with 4% increase in water footprint for sorghum. On balance, sorghum provides a climate-resilient alternative to wheat for expansion in rabi cereals. However, yields need to increase to make sorghum competitive for farmer profits and efficient use of land to provide nutrients.

Climate Change and Its Impact on Crop Water Requirement of Mulberry (Morus spp., Moraceae) Crop in Yadgir District, Karnataka, India

This study was carried out to examine trends in crop water requirement under several climate change scenarios to provide projections of changes in crop water requirement of mulberry. According to Indian Network for Climate Change Assessment (INCCA) and Inter-Governmental Panel for Climate Change (IPCC), scenarios which may be included for assessment were developed from their reports. A CROPWAT-8.0 model was utilized to determine the required water requirements for crops in a variety of climate change scenarios. The estimated and demonstrated growing and reducing trend in crop water requirements of Mulberry over the last 35 years was seen in the Yadgir district in overall displayed. As regards Mulberry, there has been a rising ETc tendency in all study area even if different climate change scenarios are used. It was found that climate variability has an impact on the Mulberry crop's water needs. To help address this, it was suggested that to reduce the risk of yield loss due to changing water availability, water conservation efforts such as rainwater harvesting, soil and water conservation, and increased ground water recharge should be implemented in the study area.

Effect of Different Irrigation Levels and Mulching Methods on Performance of Organically Cultivated and Drip Irrigated Papaya

An experiment was conducted at research field of Deendayal Upadhyay Centre of Excellence for Organic Farming, CCS HAU, Hisar during the year 2021-22 to study the effect of different irrigation levels and mulching methods on performance of organically cultivated and drip irrigated papaya. The experiment comprised of nine treatments three different irrigation levels viz. 50%, 75% and 100% of crop water requirement and three mulching methods. The results showed that the plant height (238 cm), stem girth (45.93 cm), crown diameter (242.67 cm), number of fruits (42.33), yield per plant (53.80 kg) and total yield (134.50 t ha-1) were observed maximum for meeting 100% of crop water requirement with the application of straw mulch and minimum for meeting 50% of crop water requirement without mulch condition. The soil moisture was found maximum for meeting 100% of crop water requirement with the application of plastic mulch minimum for meeting 50 % of crop water requirement without mulch condition. From the results, it is also observed that the irrigation water use efficiency (59.02 kg m-3) was found maximum for meeting 50 % of crop water requirement with straw mulch and minimum (42.64 kg m-3) for meeting 100% of crop water requirement without mulch under drip irrigation system.

Dependence of evapotranspiration validity on shallow groundwater in arid area-a three years field observation experiment

Groundwater resources strongly support crop water requirement and economic yield improvement in semi-arid and arid areas. Water resources management require more investigation in the response of evapotranspiration (ET) partitioning and water use efficiency to groundwater change. Observational data collected over a three-year period, including water and carbon flux, vegetable sap flow, meteorological factors, soil water content, and groundwater depth, were employed in this study. Additionally, an improved Shuttleworth-Wallace model was used for partitioning plant transpiration and bare soil evaporation (E) in a sunflower cropland with shallow groundwater. The ET of the sunflower was founded to be 353.5 ± 15.0 mm, and approximately 48.3 ± 7.4% derived from the groundwater evaporation. E amounted approximately 145.6 ± 6.1 mm over the growth season, and around 47.2% of which was lost during the seeding stage. Furthermore, its dynamics depended on crop growth and groundwater table depth (WTD). These large amounts of non-productive soil E had a negative impact on the water-carbon coupling. The presence of E had resulted in a lower ecosystem water use efficiency (WUEe), measured at 1.02 ± 0.33 g C kg−1 H2O, compared to canopy water use efficiency (WUEc) of 1.68 ± 0.41 g C kg−1 H2O. These results demonstrated that regulating WTD could improve WUEe by increasing WUEc and reducing soil E. To achieve the higher WUEe, an optimum WTD was range of 1.5–2.0 m for border-irrigated sunflower field grown on sandy loam, identified by an analysis of normalized evaporation difference at the varying WTD. This finding highlights the significance of maintaining specified WTD, providing valuable insights into the complex interplay between crop evapotranspiration components and shallow groundwater. Moreover, it offers guidance for precision agriculture irrigation practices.

Direct Seeded Rice as Resource Efficient Technology

In Asia, seedlings are typically transplanted into puddled soil to cultivate rice (Oryza sativa L.). Due of the manpower, water, and energy requirements of this manufacturing system, it is becoming less lucrative as these resources become more scarce. Additionally, it impairs the soil's physical qualities, negatively impacts the performance of succeeding upland crops, and increases methane emissions. Different issues, such as a declining water table, a manpower shortage during peak seasons, and worsening soil quality, need the use of alternate establishment techniques to maintain both natural resource and rice yield. Due to its low input requirement, ability to reduce greenhouse gas emissions, and ability to adjust to climatic hazards, the direct seeded rice (DSR) technique has gained a lot of attention and popularity in recent years. Dry seed must be sown into a ready seedbed, while pre-germinated seed must be sown into standing water and puddles of soil. Many farmers have switched from transplanted to DSR culture as a result of the introduction of early maturing cultivars, the application of effective fertiliser management techniques, and increased adoption of integrated weed management strategies. In certain industrialised nations, such the USA, Australia, Japan, China, and Korea, DSR technology is heavily mechanised. By switching from conventional rice to DSR, crop water requirements, soil organic matter turnover, improved nutrient management, carbon sequestration, weed management, greenhouse gas emissions, and crop intensification will all be significantly reduced. The transition from PTR to DSR is hampered by a number of factors, including a high weed infestation, the development of weedy rice, an increase in soil-borne diseases (nematodes), nutritional disorders, poor crop establishment, lodging, the prevalence of blast, brown leaf spot, etc. By addressing these limitations, DSR may show to be a very viable, economically and technically viable substitute for PTR.