Soybean seed protein concentration has declined over decades of yield-focused breeding, and new management strategies are desired to improve seed composition for end users. Sulfur and nitrogen metabolism are linked, and substantial quantities of each are required for seed storage protein production. In a field experiment at two sites in the Southeast U.S., sulfur applied at planting did not affect total protein production but increased seed protein concentration at one site, while yield was not affected. The variable impact on seed composition without a yield benefit suggests that sulfur application may not be a practical quality-improvement strategy for growers in the Southeast U.S., and these results highlight the complex relationship between sulfur availability and soybean seed quality.

Soybean physiology, seed yield and composition can vary greatly and are a function of genetics, environment, and management practices. N fertilizer is not often applied to soybeans, but it can affect yield and seed composition, and the outcome of N fertilization has varied widely among studies. To test if certain physiological responses might be linked with positive agronomic responses to N fertilizer, a field study was conducted in varied environments unique to the Southeast United States (US). Five genotypes from maturity groups V-VII were evaluated. Although the environment and genotype had significant effects on most of the physiological characteristics and yield components measured, nitrogen application interacted significantly with environment for seed protein concentration, seed oil concentration, yield, and percent of nitrogen derived from the atmosphere in leaves during the seed fill period. The direction of the nitrogen effect on protein concentration differed among environments, increasing protein concentration in one environment and reducing protein concentration in another environment. Nitrogen application effects did not vary among the genotypes included in this study. Photosynthetic and nitrogen fixation responses to nitrogen application were not clearly linked with seed protein concentration response. A tailored nitrogen recommendation for environment is the best option for improving seed protein in this region with diverse environmental conditions.

This is digital research data corresponding to a published manuscript, "Using NDVI For Variable Rate Cotton Irrigation Prescriptions", in Applied Engineering in Agriculture, 2022, Volume 38(5): 787-795. doi:10.13031/aea.15071. Irrigation timing is crucial for achieving high cotton yields and lint quality. This irrigation timing is more challenging in the southeastern U.S. Coastal Plain region due to its spatial variable sandy soils with low water and nutrient holding capacities and rainfall variability during the growing season. To address these challenges, we conducted a 2-year (2017 and 2018) study evaluating two irrigation scheduling methods under a variable rate irrigation system. The two irrigation methods were: (1) a uniform irrigation management based on weekly crop water usage, and (2) spatial crop coefficients derived from normalized difference vegetation indices (NDVI). We compared cotton yields and water use efficiency using the two irrigation scheduling methods at two different planting densities. The two plant populations were 5 and 11.5 plants m-1 of row to provide different NDVI readings and water requirements.

Management decisions like planting density and tillage could influence soybean seed composition through their impacts on competition and soil properties. To determine if either of these management decisions could help improve soybean [Glycine max (L.) Merr.] seed quality in the southeastern United States, field experiments were conducted to evaluate the impact of planting density and tillage on seed composition. Five soybean genotypes were examined in multiple environments across three plant densities from 204,000 to 476,000 plants ha(-1), and in conventional tillage compared to no-till. In two of the three environments, seed protein concentration was higher at higher plant densities. Tillage did not affect seed protein concentration, but conventional tillage improved yield when compared with no-till in two of four environments, resulting in higher protein yield under conventional tillage in these environments. Plant density may be an important management decision to consider for improving soybean seed protein in specific environments in the southeastern United States, and further research could help determine the specific environmental attributes that lead to a density benefit for seed protein.

Potential new sources of phosphorus (P) fertilizer are the recovered P from livestock wastewater through chemical precipitation and the ash from combusting animal manures. Although most of the research on P losses from conservation tillage include high water-soluble P compounds from commercial fertilizer sources, infor-mation on the use of non-conventional, low water-soluble, recycled P sources is scarce. Particularly for sandy soils of the United States (US) Southeastern Coastal Plain region, research driven information on P loss into the environment is needed to determine recommendations for a direct use of new recycled P sources as crop P fertilizers. The objective of this study is to investigate the potential P runoff from sandy soils under conservation tillage, fertilized with recovered P from liquid swine manure and turkey litter ash in comparison with com-mercial P fertilizer triple superphosphate (TSP). The field study included two typical sandy soils of the US Southeastern Coastal Plain region, the Noboco and Norfolk. Simulated rain corresponding to the annual 30-min rainfall in the study site (Florence County, South Carolina) was applied to plots treated with recovered P from liquid swine manure, turkey litter ash, and TSP, including a control with no P added. The runoff was monitored and sampled every 5 min during the test and composite soil samples were collected from the top (0-15 cm) and subsurface (15-30 cm) soil layers in each plot. Laboratory analyses were conducted to quantify both total P (TP) and soluble reactive P (SRP) in runoff samples, and the soil test P in the soil layers. Two-way analyses of vari-ances show significant treatment effects on both TP and SRP runoff. The quantities of SRP runoff from plots treated with the recovered P from swine manure and turkey litter ash represent respectively 1% and 7-8% of SRP runoff from plots treated with TSP. Hence, the use of the recovered P materials as crop P fertilizers through surface broadcast application present less environmental risks compared to commercial TSP.

This is digital research data corresponding to a published manuscript, "Using NDVI For Variable Rate Cotton Irrigation Prescriptions", in Applied Engineering in Agriculture, 2022, Volume 38(5): 787-795. doi:10.13031/aea.15071. Irrigation timing is crucial for achieving high cotton yields and lint quality. This irrigation timing is more challenging in the southeastern U.S. Coastal Plain region due to its spatial variable sandy soils with low water and nutrient holding capacities and rainfall variability during the growing season. To address these challenges, we conducted a 2-year (2017 and 2018) study evaluating two irrigation scheduling methods under a variable rate irrigation system. The two irrigation methods were: (1) a uniform irrigation management based on weekly crop water usage, and (2) spatial crop coefficients derived from normalized difference vegetation indices (NDVI). We compared cotton yields and water use efficiency using the two irrigation scheduling methods at two different planting densities. The two plant populations were 5 and 11.5 plants m-1 of row to provide different NDVI readings and water requirements.

HighlightsCrop coefficients (Kcb) were calculated using Normalized Difference Vegetative Indices (NDVI) and compared to the FAO-56 method.Cotton yields using NDVI-Kcb based irrigation scheduling to a uniform checkbook irrigation were compared.Irrigated cotton yields were not significantly different between irrigation methods but were significantly higher in years requiring higher volumes of irrigation water.Cotton fiber quality was not significantly different for the two irrigation methods or plant populations.Abstract. Irrigation timing is crucial for achieving high cotton yields and lint quality. This irrigation timing is more challenging in the southeastern U.S. Coastal Plain region due to its spatial variable sandy soils with low water and nutrient holding capacities and rainfall variability during the growing season. To address these challenges, we conducted a 2-year (2017 and 2018) study evaluating two irrigation scheduling methods under a variable rate irrigation system. The two irrigation methods were: (1) a uniform irrigation management based on weekly crop water usage, and (2) spatial crop coefficients derived from normalized difference vegetative indices (NDVI). We compared cotton yields and water use efficiency using the two irrigation scheduling methods at two different planting densities. The two plant populations were 5 and 11.5 plants m2 to provide different NDVI readings and water requirements. In 2017, there were no significant differences in cotton yields due to the adequate rainfall during the growing season that required only three irrigations events. The mean irrigation depth for the NDVI method was significantly lower than the uniform method (56 and 64 mm, respectively, LSD = 4.2). In 2018, there was lower rainfall during the growing season requiring eight irrigation events and the cotton yields in the two irrigation treatments were significantly higher than the rainfed treatment. Irrigation depths in 2018 were not significantly different for the two irrigation methods. Water use efficiencies were not significantly different for the two irrigation methods. The planting density had little impact on the cotton yields, irrigation depth, water use efficiency, or cotton fiber quality. These results indicate that the NDVI-derived crop coefficient values were as effective in prescribing irrigation applications as the uniform irrigation method for irrigation management. The NDVI-derived crop coefficient irrigation method appears to be a useful tool for managing irrigation and developing irrigation prescriptions. Keywords: Cotton, Irrigation scheduling, Normalized difference vegetation indices, Variable rate irrigation

Novel biotechnology on transgenic plants capable of metabolizing phosphite (Phi), a reduced form of P, could improve the effectiveness of P fertilizers and reduce the P footprint in agriculture with the benefit of suppressing weed growth. However, potassium Phi (K-Phi) salts used as fertilizer are highly soluble in water. At the same time, sandy soils of the Southern Coastal Plain are vulnerable to leaching losses resulting from long-term Pi fertilizer application. We performed a replicated leaching trial using five soil materials that included three surface and two subsurface layers from cultivated topsoil (Ap horizon) with contrasting Phi and Pi sorption capacities. Each soil received three treatments K-Phi at rates 0 (control), 24, and 49 kg P ha−1 and leached twice with de-ionized water. All K-Phi-treated soils leached Phi except for the controls. A phosphorus saturation ratio (PSR) calculated from P, Al, and Fe in acid extracts indicated increasing environmental risk of Phi leaching in soils with lower Phi and Pi sorption capacities at rising rates of applied K-Phi. Because plants rapidly absorb Phi, further studies on the environmental impact of K-Phi fertilizer use should include the interaction of plants with soil properties and soil microbial activity at optimal Phi application rates for growing transgenic plants able to use Phi as a nutrient source.

Conservation tillage is reported to increase soil organic carbon (SOC) and total nitrogen (TN) contents, but long-term (>30 yr) field results quantifying the responses in Coastal Plain Ultisols are sparse. The distribution, accumulation, and topsoil storage of SOC and TN after 37 yr of crop production using conventional (CvT) or conservation tillage (CnT) on a Norfolk loamy sand (fine-loamy, kaolinitic, thermic, Typic Kandiudults) were quantified. Soil samples were collected annually from the 0-5-, 5-10-, and 10-15-cm depth increments beneath corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and cotton (Gossypium hirsutum L.) crops. Overall, SOC and TN accumulation in the 0-5-cm depth were highest for Norfolk soil under CnT. Focusing on total long-term changes for the 0-15-cm sampling depth beneath various corn crops shows that CnT and CvT sequestered 24.7 and 21.4 Mg C ha(-1), respectively. Between 1978 and 2016, there was a highly significant (P < .0001) exponential increase in SOC within the top 5-cm soil depth. However, the exponential curves began to plateau suggesting the Norfolk topsoil was approaching its organic carbon (OC) storage capacity. These field measurements strongly indicate that additional topsoil SOC increases with current tillage and crop management practices are limited.

The soil nitrogen (N) availability and urease activity (UA) in a humid ecosystem with variable rainfall distribution and poor soil fertility are not well understood. A complete appreciation of N cycling in the soil–water–plant continuum is needed to better manage N and water in regions that will be strongly affected by climate change. A sorghum (Sorghum bicolor L.) study located in Florence, South Carolina, USA, was conducted using a variable-rate pivot system. We hypothesized that supplemental irrigation (SI) and N would enhance UA and N uptake while minimizing the concentration of N in porewater (TINW). The aim of the study was to assess the impact of SI (0, 50, and 100%) and N fertilization (0, 85, and 170 kg N ha−1) on: UA; total N (TNS); total inorganic N (TINS); TINW; and N uptake of sorghum. Results support our research hypothesis. The greatest UA was from 0% SI and 170 kg ha−1 (18.7 µg N g−1 ha−1). Porewater N (mg L−1), when averaged across SI and N showed a significantly lower concentration at lower soil depth (9.9 ± 0.7) than the upper depth (26.1 ± 2.4). The 100% SI had the greatest biomass N uptake (NUPB) of 67.9 ± 31.1 kg ha−1 and grain N uptake (NUG) of 52.7 ± 20.5 kg ha−1. The greatest NUPB (70.9 ± 30.3 kg ha−1) and NUG (55.3 ± 16.5 kg ha−1) was from the application of 170 kg N ha−1. Overall, results showed that proper use of water and N enhanced soil N dynamics, and improved biomass productivity and N uptake of sorghum.

HighlightsA decision support system using the USDA-ARS Irrigation Scheduling and Supervisory Control and Data Acquisition (ISSCADA) system was evaluated for spatially managing corn irrigation in the U.S. Eastern Coastal Plain.The ISSCADA system was compared to traditional scheduling methods based on measured soil water potentials.The ISSCADA system with feedback on allowable soil water depletion shows potential as a tool for growers for managing variable-rate irrigation systems.Abstract. Variable-rate irrigation (VRI) systems are capable of applying different water depths both in the direction of travel and along the length of the irrigation system. VRI systems maybe useful for improving crop water management and efficiency. Although VRI technology is available and has high grower interest, it has had limited adoption. To address this, researchers have developed a decision support system that uses remote sensing of plant, soil, and microclimate to schedule VRI irrigations. In this research, we evaluated the use of the USDA-ARS Irrigation Scheduling and Supervisory Control and Data Acquisition (ISSCADA) system for spatially managing corn irrigation in the U.S. Eastern Coastal Plain. The ISSCADA system consists of center pivot mounted infrared thermometers (IRT) to measure crop canopy temperatures and in situ soil water sensors. An integrated crop water stress index (iCWSI) was calculated from the canopy temperatures. The ISSCADA system analyzes the iCWSI and soil water measurements to provide an irrigation recommendation. The ISSCADA system was evaluated using (1) iCWSI values and (2) a hybrid ISSCADA system that incorporated both iCWSI values and soil water depletion criteria. These ISSCADA treatments were compared to traditional irrigation management using measured soil water potentials. The ISSCADA system was evaluated for four years. In 2016 and 2017, corn yields and water use efficiency were not significantly different between the irrigation treatments due to adequate rainfall during the growing season. In 2018 and 2019, mid-season drought conditions and sporadic rainfall patterns required frequent irrigations. In both years, the irrigation treatment corn yields were not significantly different from each other but were greater than the rainfed yields. In 2018, the irrigation treatments produced corn yields of 10.7, 10.4, and 10.1 Mg ha-1 for the hybrid, ISSCADA, and SWP treatments, respectively. Over the four-year study, the water use efficiencies of the irrigation treatments were not significantly different from each other or the rainfed treatment and ranged from 16.6 to 22.7 kg ha-1 mm-1. In the two years that the hybrid ISSCADA system was used for managing irrigations, it produced higher corn yields and required less irrigation than the standard ISSCADA treatments. Results from this experiment will help to evaluate and refine the ISSCADA system to provide a tool for growers to use in managing spatial irrigation with VRI systems. Keywords: Crop water stress, Decision support system, Variable rate irrigation.

Low use-efficiency and high environmental significance of phosphorus (P) requires a better understanding of its stocks and behavior in soils. We investigated P fractions in sandy Coastal Plain Ultisols, where long-term conservation agriculture driven by conservation tillage and residue return for similar to 40 yr and the integration of cover cropping for 4 yr has been demonstrated to improve soil organic matter. Soils were collected from fields at 0- to 5- and 5- to 15-cm depths to study the effects of tillage (conservation vs. conventional) and cover crop (with vs. without) on soil stocks of various chemically defined P pools and the phosphatase potential activities. Conservation tillage increased KCl-extractable inorganic P (KCl-Pi) stocks in top soils (0-5 cm) when compared to conventional tillage, but had no effects on other pools at both soil depths. Cover cropping caused significant accumulations of NaOH-extractable organic P (NaOH-Po) in top soils (0-5 cm). Nonetheless, neither conservation tillage nor cover crop changed the contributions of the chemically defined pools to soil total P with NaOH-Po dominating at both soil depths followed by NaOH-extractable inorganic P (NaOH-Pi) and HCl-extractable Pi (HCl-Pi). Conservation tillage increased phosphatase potential activities by 128% in the 0- to 5-cm soils, whereas no cover crop effects were observed. Conservation tillage improved P availability potentially through its effects on microbial activities, whereas cover cropping increased P stocks and availability by promoting Po accumulations.

Ash from power plants that incinerate poultry litter has fertilizer value, but research is lacking on optimal land application methodologies. Experiments were conducted to evaluate calcitic lime and flue gas desulfurization gypsum (FGDG) as potential fillers for poultry litter ash land applications. The ash had phosphorus (P) and potassium (K) contents of 68 and 59 g kg−1, respectively. Soil extractable P and K were measured in an incubation pot study, comparing calcitic lime to FGDG at filler/ash ratios of 1:3, 1:2, 1:1, 2:1, and 3:1. After one month, soils were sampled and annual ryegrass (Lolium multiflorum Lam.) seeds were planted to investigate how plant growth and uptake of P and K were influenced by the fillers. Application of ash alone or with fillers increased soil extractable P and K levels above unamended controls by 100% and 70%, respectively. Filler materials did not affect biomass or P and K concentration of the ryegrass. A field study with a commercial spinner disc fertilizer applicator was conducted to compare application uniformity of ash alone and filler/ash blends. Overall, test data suggested that uniform distribution of ash alone or with fillers is feasible in field applications using a commercial fertilizer spreader.

A 4-yr study was conducted to determine the degree of aggregation of thrips and injury in cotton, Gossypium hirsutum L., and their spatial association with a multispectral vegetation index (normalized difference vegetation index [NDVI]) and soil apparent electrical conductivity (ECa). Using the Spatial Analysis by Distance IndicEs analyses (SADIE), adult thrips were significantly (P < 0.05) aggregated in 4 out of 24 analyses for adult thrips (17%), 4 out of 24 analyses for immature thrips (17%), and 2 out of 15 analyses for injury (13%). The SADIE association tool showed that NDVI values were associated with adult thrips in 2 out of 20 paired datasets (10%), with immature thrips in 3 out of 20 paired datasets (15%), and with thrips injury in 1 out of 14 paired datasets (7.1%). Soil ECa values were generally more associated with thrips variables than NDVI, with shallow ECa positively associated with adult thrips in 6 out of 21 paired datasets (28.6%), with immature thrips in 8 out of 21 paired datasets (40.0%), and with thrips injury in 8 out of 14 paired datasets (57.1%). The greater frequency of positive associations between thrips variables and soil ECa suggests a greater potential for site-specific management, particularly in the Coastal Plain of the southeastern United States, where soil types are highly variable.

Over the last two decades, signs of precipitation irregularity were frequently reported across the Southeastern United States (US). Even though the region receives a relatively high annual precipitation, the precipitation events are not equally distributed in the time and space. Hence, rainfed agriculture, a common practice in the region is threatened by changes in precipitation frequencies during the crop growing seasons. With this situation, a better understanding of the actual patterns of precipitation irregularity is needed to support the local agriculture. This study uses a spatial regionalization approach to delineate precipitation regions for an area spanning the states of South Carolina, North Carolina, and Georgia. The data used include time-series of seasonal precipitation totals and seasonal numbers of precipitation events > 5mm over the period 1960-2017. A regionalization method which combines principal components and cluster analyses was applied to 208 precipitation stations selected across the study region. Finally, three precipitation regions were delineated based on statistics and similarity criteria. A comparative analysis of these three regions shows significant differences in the seasonal precipitation totals and the seasonal number of precipitation events. In addition, the differences were examined using a probabilistic approach. As a result, tables of probabilities and seasonal precipitation characteristics (precipitation totals and number of events > 5 mm) were generated for each region. These tables could provide information about the chances of precipitation deficits or excesses relatively to a crop and henceforth be useful for agricultural water use planning.

Abstract. Site-specific variable-rate irrigation (VRI) systems can be used to spatially manage irrigation within sub-field-sized zones and optimize spatial water use efficiency. The goal of the research is to provide farmers and consultants a tool to evaluate the potential benefits of implementing VRI. The specific objective of this research is to evaluate the potential water savings using VRI management compared with uniform irrigation management to maintain soil water holding capacity above 50% depletion using two irrigation scenarios: 1) a standard 12.5 mm irrigation per application; and 2) an application to refill the soil profile to field capacity. A 21-year simulation study was carried out on a selected field with varying degrees of soil and topographic variability. The simulated field had 12 soil mapping units with water holding capacities in the top 0.30-m ranging from 42 to 70 mm. The 21-year simulation covering all weather conditions for each soil produced only two significantly different irrigation management zones for scenario 1, and for scenario 2 only one management zone. However, when the 21-year period was divided into periods with different ratios of rainfall to reference evapotranspiration, the simulations identified 1 to 5 management zones with significantly different irrigation requirements. These results indicate that variable rate irrigation system design and management should not be solely based on long term average weather conditions. Years with differing weather conditions should be used for potentially identifying management zones for VRI systems. Irrigation application depths between management zones ranged from 17 to 38 mm. However, when the actual soil areas of the study field were utilized to calculate the total volume of irrigation water applied, it resulted in an increase in water usage in the 2 and 4 management zones ranging from -1.2% to 5.8%. Water usage with VRI over uniform irrigation was greater by -1.6% to 6.8% in the 12.5 mm irrigations and by -1.2% to 2.2% for the field capacity irrigations Keywords: Management zones, Precision farming, Variable-rate irrigation, Water conservation.

Controlling for experimental error attributable to field heterogeneity is important in high‐throughput phenotyping studies that enable large numbers of genotypes to be evaluated across time and space. In the current study, we compared the efficacy of different experimental designs and spatial models in the analysis of canopy spectral reflectance data collected on upland cotton (Gossypium hirsutum L.). Canopy spectral reflectance, as measured by normalized difference vegetation index (NDVI), was measured at first bloom on three upland cotton performance trials conducted in Florence, SC, during 2014 and 2015. The relative efficiency and estimates of genotype effects were compared among randomized complete block, an α‐lattice incomplete block, row–column incomplete block, nearest neighbor adjusted, and spatially correlated error models. The row–column model provided the greatest improvement in the precision of genotype effect estimates compared with the randomized complete block model. Genotype rankings based on NDVI varied substantially between the randomized complete block and alternative models, particularly at 5 and 10% selection intensities. These results suggest that the use of more complex experimental designs and spatial analyses should be routinely considered to minimize experimental error due to field heterogeneity and improve the precision and reliability of traits measured using high‐throughput phenotyping systems. These findings also indicate that further research into the effects of field heterogeneity on the relationship between NDVI and lint yield in upland cotton is warranted.

Grain sorghum is one of the top five cereal crops and an important grain crop throughout the world. It is generally considered more drought tolerant compared to other grain crops such as maize. Recently, in the U.S. eastern Coastal Plain region, there was an emphasis on increasing regional grain production in which grain sorghum played an important role. The region's soils have low water holding capacities that combined with high rainfall variability cause crops frequently to be exposed to water stress. In this research, an experiment was conducted to evaluate the yield response of two grain sorghum varieties at different supplemental irrigation depths and three nitrogen levels. During our 3-year study, seasonal rainfall was adequate to produce acceptable grain sorghum yields. Seasonal rainfall ranged from 421, 365, and 357 mm in 2012, 2013, and 2014, respectively. These rainfall amounts were greater than the seasonal calculated crop evapotranspiration requirement, but rainfall distribution was not adequate to maintain acceptable soil water potentials throughout the growing season. Supplemental irrigation was 51, 38, and 13 mm in 2012, 2013, and 2014, respectively, to maintain soil water potential above -30 kPa. These irrigation amounts did not increase grain sorghum yields. No significant differences were found in grain yield between the two sorghum varieties or for increasing nitrogen applications. This lack of response to nitrogen applications may have been related to adequate supplies in the soil from previous crops. Results from this study suggest that there would be little benefit for supplemental irrigation for sorghum production in the U.S. eastern Coastal Plain.

Core Ideas Effective use of water and N improved biomass and nutrient use efficiency of sorghum. Sorghum applied with N and 100% irrigation had the greatest biomass. Sorghum with 85 kg N ha –1 and 100% irrigation had the greatest nutrient use efficiency. Poor rainfall distribution and poor soil fertility in the humid coastal plain region may affect grain crop production. Nitrogen insufficiency and water stress can both reduce crop yield, but little information is available on whether supplemental irrigation (SI) and N fertilization can alleviate both water stress and nutrient deficiency in humid regions. A field sorghum [ Sorghum bicolor (L.) Moench] study was conducted under a variable‐rate center pivot. The objective of our study was to determine the combined effects of N fertilization (0, 85, and 170 kg N ha −1 ) and SI (0, 50, and 100% of the full irrigation rate) on aboveground biomass (AB), nitrogen uptake (NU), and nitrogen‐use efficiency (NUE) of two varieties (VAR) of grain sorghum in coastal plain region of the United States. Aboveground biomass and NU varied with SI ( p ≤ 0.001) and levels of N ( p ≤ 0.001). In irrigated treatments, the rates of 85 and 170 kg N ha −1 resulted in significantly higher AB, NU, and NUE. Averaged across years, VAR, N and SI, grain sorghum applied with 170 kg N ha −1 and 100% SI had the greatest AB of 3997 kg ha −1 . Sorghum with 85 and 170 kg N ha −1 and 100% SI treatment had the greatest NUE of 60.5 and 57.1%, respectively. Our results support our hypothesis that negative impacts of water stress and nutrient deficiency could be mitigated by SI and N fertilization. Effective water use in irrigation and maintaining a sufficient amount of N will improve the AB, NU, and NUE of grain sorghum.