Fertilizer Application Methods Research Articles

Productivity of columnar apple tree depending on fertilizer application and drip irrigation methods

Mineral nutrition and water regime of soils affect significantly the yield and fruit quality of apple trees. In this connection, the present study was aimed at determining the effectiveness of different fertilization methods under drip irrigation on the productivity of columnar apple trees grown on sod-podzolic soils. Field experiments conducted in 2021–2023 involved the following variants: (1) without fertilizers and drip irrigation control (control); (2) drip irrigation; (3) drip irrigation + N90K90 (solid); (4) drip irrigation + N90K90 fertigation. It was found that both drip irrigation alone and fertilization methods have a different effect on the productivity of columnar apple trees, largely depending on the genetic features of the variety and weather conditions. The highest tree productivity was achieved in the variant of drip irrigation in combination with N90K90 in the form of solid fertilizers. The President and Ostankino varieties showed an increase in productivity by 11.2 % and 18.5 %, respectively, compared to the control. The vegetation productivity dynamics depended on the genetic features of the variety to a greater extent. Thus, in similar experimental variants, the total growth length of the President variety exceeded that of the Ostankino variety by 45.4 %. The application of drip irrigation and fertilization methods contributed to an increase in the vegetation productivity of the President variety by an average of 18.3 % compared to the control. Conversely, the Ostankino variety showed a minor decrease in the activity of growth processes in the experimental variants. The content of chlorophyll (a + b) in leaves varied by years, experimental variants, and the interaction of factors. Chlorophyll fluorescence in leaves (Fm/F0) was significantly influenced by the years of research. To a lesser extent, the efficiency of phytosystem II was infl uenced by irrigation and fertilization methods.

Soil Nutrient Changes in Black Soil of Northeastern China Under Long-Term Cultivation with Different Fertilizer Applications and Tillage Patterns: A Meta-Analysis

ABSTRACT As one of the four major black soil distribution areas in the world, the black soil region in northeastern China has shown a trend of nutrient degradation under excessive development. Understanding its nutrient changes and the factors affecting them is of great significance to the sustainable development of black soil. Soil nutrient profiles are influenced by several anthropogenic management patterns, including fertilizer application methods and tillage practices. A comprehensive analysis of the influencing factors can help to understand the mechanisms of nutrient changes in black soil cropland. Therefore, using soil organic carbon (SOC) as a proxy for nutrients, this study applied a meta-analysis based on 1138 observations from 60 papers to reveal the effects of anthropogenic management practices (application of organic fertilizers (OF), straw back (SB), application of chemical fertilizers (CF) and conservational tillage (CT)) on soil nutrients. The results showed that the most of soil nutrients increased significantly under management model. The application of chemical fertilizers decreased soil pH by 4.55% and increased soil available phosphorus (AP) content by 112.14%. Compared to the conventional model, application of organic fertilizers significantly increased SOC content, total nitrogen (TN) content and microbial biomass carbon (MBC) content by, 16.75%, 20.10% and 31.15% (p < .05), respectively. The effect values of SOC content were positively correlated with those of most soil nutrient contents under different anthropogenic management. This study helps to understand the response of nutrient content of northeastern black soils to different anthropogenic management models and provides reasonable references for sustainable farming patterns.

Studies on the effect of surface and subsurface methods of irrigation and method of fertilizer application on growth and yield parameters, yield, economics and water use efficiency in sugarcane

Studies on the effect of surface and subsurface methods of irrigation and method of fertilizer application on growth and yield parameters, yield, economics and water use efficiency in sugarcane

The nitrogen supply capacity and application methods of straw-chemical mixed fertilizer in the sweet corn variety ‘Zhetian 19’

The global production of crop straw has been steadily increasing as the demand for crops continues to grow, with current output reaching approximately 4 billion tons annually. Crop straw is a nutrient-rich resource, but if not properly managed, it can pose environmental risks. Effective utilization of straw remains a significant challenge in agricultural production. To address environmental issues such as pollution from straw burning, soil degradation, low crop germination rates, and the increase in soil-borne diseases, this study adopts the "organic-inorganic granular fertilizer" method. By converting straw into granulated fertilizer and returning it to the field, this approach not only repurposes agricultural waste but also enhances soil quality and crop yields. A three-year field experiment (2020–2022) was conducted to investigate the effects of various application rates of SCMF (Straw Chemical Mixed Fertilizer) and optimal fertilization methods on the photosynthetic process, yield, soil nutrients, and sugar content of sweet corn. In 2020, SCMF and urea were applied to plots according to different fertilization methods and rates: S0, SUT0.5, SUT, SUB0.5, SUB, CK0, and CK. In 2021, based on the optimal fertilization rate identified in 2020, different fertilization methods were tested: SUT, SUB0.5UT0.5, SUB, CK0, and CK.In 2022, under the optimal fertilization method, SCMF application rates were adjusted according to a 10 % variation in nitrogen fertilizer content: S1.2UB, S1.1UB, SUB, S0.9UB, S0, CK0, and CK.Considering the chlorophyll content, leaf area index, dry matter accumulation, yield, soil nutrient status, and sugar concentration in sweet corn from 2020 to 2022, the SUB treatment demonstrated superior performance. Compared to CK (247.2 kg N ha−1), the SUB treatment (229.2 kg N ha−1) enhanced both the yield and quality of sweet corn, while SCMF applications led to an increase in sugar content. In 2022, the SUB treatment resulted in a 9.5 % increase in chlorophyll content, and the leaf area index at 10 days after planting (DAP) was the highest observed. This increase in leaf area index contributed to a higher accumulation of dry matter (6.3 %) and ultimately led to an 8.7 % increase in sweet corn yield and a 9.7 % increase in soluble sugar content. The findings suggest that the SUB fertilization rate and method are optimal for achieving higher chlorophyll content, leaf area index, yield, and soluble sugar concentration in sweet corn. Additionally, soil nutrient analyses indicated that SCMF applications improved soil pH, total nitrogen, and organic matter content.Therefore, the SUB treatment resulted in increased chlorophyll content and leaf area index, enhancing photosynthetic efficiency and providing a larger area for dry matter accumulation and yield. The application of SUB reduced nitrogen fertilizer input by 20 % while increasing sweet corn yield, contributing to higher agricultural productivity and offering an innovative strategy for the efficient management of crop straw residues. Further research is required to investigate the dynamics of straw decomposition products in enriching soil nutrients, their absorption rate by sweet corn, and their influence on soil enzyme activity and microbial community structure.

Transforming Irrigated Agriculture in Semi-Arid and Dry Subhumid Mediterranean Conditions: A Case of Protected Cucumber Cultivation

Pressure from population growth and climate change stress the limited water resources in the Mediterranean region and threaten food security and social stability. Enhancing food production requires the transformation of irrigation systems and enhancement of local capacity for sustainable water and soil management in irrigated agriculture. The aim of this work is the conversion of traditional irrigation practices, by introducing the practice of optimal irrigation scheduling based on local ET estimation and soil moisture monitoring, and the use of continuous feeding by fertigation to enhance both water and nutrient use efficiency. For this, two trials were established between August and November 2023 in two different pedoclimatic zones (Serein and Sultan Yacoub) of the inner Bekaa Plain of Lebanon, characterized by semi-arid and dry subhumid conditions and different soil types. Greenhouse cucumber was tested to compare the prevailing traditional farmers’ practices with the advanced, technology-based, methods of water management. Results showed a significantly higher amount of water applied by the farmers to the protected cucumber, with a potential for average saving of 105 mm of water applied in each season by improved practices. Water input in the traditional practices revealed potential stress to plants. With more than 20% increase in cucumber yield by the transformed practices, a general trend was observed in the fertilization approach and amounts, resulting in lower nutrient recovery in the farmer’s plots. The science-based practices of water and nutrient management showed higher application and agronomic water use efficiency of full fertigation, exceeding 60%, associated with double and triple higher nitrogen use efficiency, compared to those results obtained by the traditional water and fertilizer application methods. The monitored factors can contribute to severe economic and environmental consequences from nutrient buildup or leaching in the soil–groundwater system in the Mediterranean region.

Effects of Long-Term Nitrogen Fertilization and Application Methods on Fruit Yield, Plant Nutrition, and Soil Chemical Properties in Highbush Blueberries

Nitrogen (N) fertilizer is routinely applied in highbush blueberry (Vaccinium corymbosum L.) production. The recommended N fertilizer rate increases as the plants mature, and is usually determined based on regional growing conditions. However, the effects of N fertilizer rates and application methods over the long term remain poorly understood. In this study, ammonium sulfate was applied as an N source at the recommended rate (100%), which corresponds to a maximum of 155 kg N ha−1 for plants older than eight years, along with higher rates at 150% and 200% of the recommended level, as well as a control treatment of no N. Treatments were applied to the blueberry cultivar ‘Duke’ as either broadcast (BROAD) or fertigation (FERT), and impacts were analyzed after 12 and 13 years of treatment. In the 14th year, the 100% N rate was uniformly applied as BROAD across all plants to separate the effects of different N rates from those caused by long-term soil condition changes. The BROAD treatment at the 100% N rate achieved the highest yield, and the FERT treatment at 200% resulted in the lowest yield in the 12th year, suggesting that excessive N rates can reduce fruit yield. However, no significant yield differences were observed in the 13th year. Higher N rates were associated with reduced titratable acidity in fruits and fewer flower buds. The soil pH declined across all N treatments, with the FERT at 200% showing the most significant reduction. All N treatments generally increased soil electrical conductivity (EC). High N rates also decreased plant accumulation of magnesium, calcium, and copper, with the latter reaching deficiency levels. These findings emphasize the importance of adhering to recommended N application rates and adjusting soil pH and EC to mitigate the adverse effects of prolonged N treatments.

Performance Assessment of the Small and Medium-Scale Coconut Weeder Cum Fertilizer Applicator Developed by Rajarata University of Sri Lanka

The enhancement of coconut yield significantly hinges on proper weeding and chemical fertilizer application. In Sri Lanka, several mechanical methods have been introduced for weeding and fertilizer application of coconut, but the traditional manual approach persists most popular, despite being time, labor cost intensive. Moreover, the introduced technologies were suited for large-scale coconut cultivation and could not cope with medium or small-scale. Furthermore, most of them are designed for a single application; weeding or fertilizing. Thus, the Faculty of Agriculture, Rajarata University of Sri Lanka (RUSL), developed a coconut weeder cum fertilizer applicator for medium and small-scale coconut cultivations. However, it has not been properly evaluated and recommended for farmers. Consequently, this study sought to evaluate the performance of the above machine by conducting a comparative performance evaluation with the conventional method. A healthy, well-maintained, proper-spacing coconut plantation was selected from the faculty research unit, and each weeding and fertilizer application method was replicated ten times. In terms of performance parameters: effective field capacity, field efficiency, and weeding efficiency in mechanical and manual methods were 0.172 ha h-1, 61.86%, 66.62%, and 0.048 ha h-1, 55.34%, 60.35%, respectively. Statistical analysis indicates the mechanical method had higher field capacity and efficiency than the manual method, while weeding efficiency was not significantly different (p≤0.05). In addition, the machine had a fertilizer spreading uniformity of around 99.98% when operating at an optimum speed of 1.45 km h-1. Fertilizer application rate and performance index as a weeder were 1.7 kg/min and 1145.86, respectively. Furthermore, the fuel consumption rate of the machine was 0.733 L h-1 and its break-even point was recorded as 2.85 ha yr-1. Consequently, the coconut weeder cum fertilizer applicator proves suitable for medium and small-scale coconut cultivations in Sri Lanka.

Preparation of Biofertilizers from Banana Peels: Their Impact on Soil and Crop Enhancement

Disposing of banana peels (BPs) as bio-organic waste is an environmental challenge. Rich in potassium, BPs are often discarded despite their agricultural value. Reports on the valorization of BP are increasing, but no review has focused on BP fertilizer preparation methods. This study aims to review and analyze these methods to guide researchers and agriculturists in optimizing BP utilization, promoting sustainable waste management, and effective agricultural practices. This review has uncovered significant findings. A composite of banana and orange peels emerged as the most favoured and widely used approach, closely followed by dried BPs. This study highlighted the substantial impact of fertilizer application methods such as top and basal dressing. Most of the results revealed that the peels significantly improved the growth parameters of various plants. However, for biochar, the plant height was insignificant between treatments, further emphasizing the importance of the application method used. Banana peels are a valuable resource for biofertilizer synthesis. The banana–orange peel composite exhibits outstanding fertilizer properties. More new studies should go beyond the seedling stage, especially to harvest. This would give more information on the performance and viability of BP fertilizers.

Crop-specific management history of phosphorus fertilizer input (CMH-P) in the croplands of the United States: reconciliation of top-down and bottom-up data sources

Abstract. Understanding and assessing the spatiotemporal patterns in crop-specific phosphorus (P) fertilizer management are crucial for enhancing crop yield and mitigating environmental problems. The existing P fertilizer dataset, derived from sales data, depicts an average application rate over total cropland at the county level but overlooks cross-crop variations. Conversely, the survey-based dataset offers crop-specific application details at the state level yet lacks inter-state variability. By reconciling these two datasets, we developed long-term gridded maps to characterize crop-specific P fertilizer application rates, timing, and methods across the contiguous US at a resolution of 4 km × 4 km from 1850 to 2022. We found that P fertilizer application rate over fertilized areas in the US increased from 0.9 g P m−2 yr−1 in 1940 to 1.9 g P m−2 yr−1 in 2022, with substantial variations among crops. However, approximately 40 % of cropland nationwide has remained unfertilized in the recent decade. The hotspots for P fertilizer use have shifted from the southeastern and eastern US to the Midwest and the Great Plains over the past century, reflecting changes in cropland area, crop choices, and P fertilizer use across different crops. Pre-planting (fall and spring) and broadcast application are prevalent among corn, soybean, and cotton in the Midwest and the Southeast, indicating a high P loss risk in these regions. In contrast, wheat and barley in the Great Plains receive the most intensive P fertilization at planting and via non-broadcast application. The P fertilizer management dataset developed in this study can advance our comprehension of agricultural P budgets and facilitate the refinement of best P fertilizer management practices to optimize crop yield and to reduce P loss. Datasets are available at https://doi.org/10.5281/zenodo.10700821 (Cao et al., 2024).

Fertilizer Micro-dosing: Evaluating the Yield Response of Sorghum to Different Levels of Fertilizers Applied on the Planting Pit at Mereb-Lekhe District

Next to drought, poor soil fertility is the single major cause of crops nutrient starvation in Tigray specifically at Mereb-lekhe district. Farmers of the study area use different organic and inorganic fertilizers separately and in combination to overcome soil fertility problems for sorghum production. However, the pace of sorghum production stays constant and occasionally decreases with time. Fertilizer efficiency; the type, rate and method of fertilizer application they use were thought to be the reasons for the steady or declining sorghum production. Hence, this study was initiated to determine the yield response of sorghum to microdose fertilizer application. The experiment was set in a randomized complete block design with three replications. The treatments were; farmers’ practice or blanket recommended nitrogen (N) and phosphorous (P) (50kg ha-1 Urea &amp; 100 kg ha-1 DAP), recommended compost at a rate of 7ton ha-1, 75% of recommended NP, 50% of recommended NP, 25% of recommended NP, 75% recommended NP+25% recommended compost, 50% recommended NP+50% recommended compost and 25% recommended NP+75% recommended compost. All treatments were applied with microdosing method except the recommended N and P is broadcasting method. The highest sorghum grain yield (4201 kg ha-1) and straw yield (19107 kg ha-1) were obtained from treatment recommended compost at a rate of 7 ton/ha and 50% recommended NP+50% recommended compost, respectively. This study showed that combined application of organic and inorganic fertilizer gave a better economic advantage for sorghum crop. Hence, it could be concluded that use of compost at a rate of 7 ton ha-1 and the 75% recommended N and P could increase production and productivity of sorghum by the application of micro dosing than broadcasting method.

EFFECTS OF INORGANIC FERTILIZER APPLICATION METHODS ON CHEMICAL COMPOSITION OF MAIZE LEAVES AS FODDER FOR LIVESTOCK

Fodder production requires nutrients for its tissue and cell developments, however its productivity is hampered by low nitrogen contents in the soil. Inorganic fertilizers are becoming expensive daily and beyond the reach of many livestock farmers that use maize leaves as fodder for their livestock. Foliar method of fertilizer application is expected to use less quantity of inorganic fertilizers compared to placement method, however, its effect on chemical composition needs to be investigated. This experiment was therefore conducted to determine the effect of method of fertilization on chemical composition of maize leaves as feed for livestock. The experiment consisted of four treatments, Treatment 1 (T1) was the application of inorganic fertilizer using side placement while Treatments 2 (T2), 3 (T3) and 4 (T4) were 20%, 40% and 60%, respectively of total amount of fertilizer applied in T1 using foliar method of application. The treatments were replicated three times making the total of 12 experimental units. The experimental design adopted was Randomized Completely Block Design (RCBD. The maize leaves were then analyzed for organic matter (OM), dry matter (DM), ASH, acid detergent fibre (ADF), neutral detergent fibre (NDF), acid detergent lignin (ADL), and crude protein (CP). The result revealed that, there was significant (p≤0.05) effect of method fertilization on the chemical composition of maize leaves (DM= 94.32-95.40%), (OM= 90.83-94.73%), (ADF= 25.15- 29.04%), (NDF= 19.05-31.72%,), (ADL= 3.10-4.33%), and (CP= (7.41-10.29%).It was concluded that application of fertilizer using foliar method at the rate of 100kg/ha NPK 20:10:10 and 50kg/ha urea could reduce rate of leaching and cost of maize production as forage for livestock.

The Application of Carbon-Based Fertilizer Changed the Microbial Composition and Co-Occurrence Network Topological Properties of Vineyard Soil

Charcoal-based fertilizer could be used extensively and is environmentally friendly. An experiment was designed to investigate the effects of different charcoal-based fertilizer application methods on soil microbiology and grape quality in a vineyard to guide the cultivation of ‘Shine-Muscat’. A control treatment without fertilization and six other treatments were set up. Four treatments applied carbon-based fertilizer as a base fertilizer with or without potassium fulvic acid, a complex microbial agent, or Bacillus subtilis, and two treatments were only applied with two applications of carbon-based fertilizer or compound fertilizer during the expansion period. The results showed that the bacterial phyla were mainly Proteobacteria and Bacteroidetes. Ascomycota, Basidiomycota, and Mortierellomycota dominated the fungal community. At the genus level, the composition of fungi, compared to bacteria, varied significantly, while the dominant flora differed among fertilization practices. Application of charcoal-based fertilizer enriched beneficial microorganisms, while chemical fertilizers enriched pathogenic microorganisms. The addition of microbial fungicides and biostimulants for a period reduced the size of the microbial network, lowered positive correlations, and enhanced resistance to adverse conditions and diseases and there was no significant correlation between agronomic traits and microbial network topology. A combination of soil microbial and grape agronomic traits suggests that a charcoal-based fertilizer base, with microbial fungicides applied, is the optimal fertilization regimen for grape.

Fertilizer and Crop Yield Prediction using Machine Learning

The agricultural sector is indispensable to feeding the growing global population, making efficient crop management and yield prediction imperative. Traditional farming practices often rely on subjective decision-making and generalized fertilizer application methods, leading to suboptimal resource utilization and yield outcomes. In this research, we introduce an innovative method Utilizing the capability the bunch of algorithms introduced for machine learning tasks to precise fertilizer recommendation and crop yield prediction. The developed system provides farmers with personalized fertilizer recommendations tailored to their specific soil and crop requirements, thereby minimizing waste and maximizing yield potential. Additionally, real-time monitoring and feedback mechanisms enable adaptive adjustments throughout the growing season, ensuring timely interventions to mitigate adverse outcomes and optimize productivity

Compost and Mineral Fertilizer Application Affects Soil Microbial Activity and Nutrient Mineralization in an Ultisol

ABSTRACT Organic additions help improve soil biophysical qualities, but they are insufficient to supply nutrient demand and could result in unintentional nutrient immobilization in soils, particularly soils with low fertility status. A 16-week laboratory incubation study was conducted to determine how the method of application of compost and inorganic fertilizers influence microbial respiration, nitrogen (N), and phosphorus (P) mineralization. Topsoil (500 g, 0–15 cm) was amended with compost (0, 5, and 10 g kg−1) and either inorganic N (50 kg N ha−1) or P (30 kg P ha−1). Two soil amendment strategies, applying compost and inorganic fertilizer separately to opposite sides of the soil using a divider and mixing them evenly throughout the soil, were compared for their effects on microbial activity and nutrient mineralization. The cumulative amounts of carbon dioxide (CO2) evolved were measured fortnightly using the static CO2 absorption method and inorganic N and P mineralization. N mineralization was unaffected by the method of compost and inorganic fertilizer application (p > .05), while at the end of day 42, available P in separate applications of compost and mineral N fertilizers was 33% greater than combined applications. Compost and inorganic P fertilizer had favorable N priming effects, but compost and inorganic N had negative effects. The different N priming effects of compost and inorganic N and P fertilizers may be attributable to microbial nutrient demand. The data suggest that composting with conventional fertilizers may change microbial nutrient demand and crop nutrient availability.

Research on fertilization decision method for rice tillering stage based on the coupling of UAV hyperspectral remote sensing and WOFOST.

The use of chemical fertilizers in rice field management directly affects rice yield. Traditional rice cultivation often relies on the experience of farmers to develop fertilization plans, which cannot be adjusted according to the fertilizer requirements of rice. At present, agricultural drones are widely used for early monitoring of rice, but due to their lack of rationality, they cannot directly guide fertilization. How to accurately apply nitrogen fertilizer during the tillering stage to stabilize rice yield is an urgent problem to be solved in the current large-scale rice production process. WOFOST is a highly mechanistic crop growth model that can effectively simulate the effects of fertilization on rice growth and development. However, due to its lack of spatial heterogeneity, its ability to simulate crop growth at the field level is weak. This study is based on UAV remote sensing to obtain hyperspectral data of rice canopy and assimilation with the WOFOST crop growth model, to study the decision-making method of nitrogen fertilizer application during the rice tillering stage. Extracting hyperspectral features of rice canopy using Continuous Projection Algorithm and constructing a hyperspectral inversion model for rice biomass based on Extreme Learning Machine. By using two data assimilation methods, Ensemble Kalman Filter and Four-Dimensional Variational, the inverted biomass of the rice biomass hyperspectral inversion model and the localized WOFOST crop growth model were assimilated, and the simulation results of the WOFOST model were corrected. With the average yield as the goal, use the WOFOST model to formulate fertilization decisions and create a fertilization prescription map to achieve precise fertilization during the tillering stage of rice. The research results indicate that the training set R2 and RMSE of the rice biomass hyperspectral inversion model are 0.953 and 0.076, respectively, while the testing set R2 and RMSE are 0.914 and 0.110, respectively. When obtaining the same yield, the fertilization strategy based on the ENKF assimilation method applied less fertilizer, reducing 5.9% compared to the standard fertilization scheme. This study enhances the rationality of unmanned aerial vehicle remote sensing machines through data assimilation, providing a new theoretical basis for the decision-making of rice fertilization.

The Effect of Organic Fertilizer Type, Nutrient Composition, and Application Method on Tomato Plant Growth in Plantation Areas in the Cianjur Region of West Java

This study investigated the effect of organic fertilizer type, nutrient composition, and application method on tomato plant growth in the plantation areas of the Cianjur region, West Java. A randomized complete block design (RCBD) with factorial arrangements was employed, and data were collected using Likert scale ratings from 110 tomato plants. The analysis revealed significant differences in plant growth among different organic fertilizer types, with biofertilizers exhibiting the highest mean growth score. Moreover, fertilizers with balanced nutrient compositions resulted in superior plant growth compared to those with imbalanced compositions. Additionally, foliar spraying emerged as the most effective application method, promoting higher plant growth compared to broadcasting and banding methods. These findings highlight the importance of considering organic fertilizer characteristics and application techniques in optimizing tomato plant growth in agricultural systems.

Effects of Nitrogen Fertilizer Management on Dry Matter Accumulation and Yield of Drip-Irrigated Sugar Beet in Arid Areas

Clarifying the optimal combination of N fertilizer application rate and application method can maximize the yield of drip-irrigated sugar beet in arid areas, which is of great significance for reducing farmland N pollution and achieving sustainable agricultural development. In this three-year field experiment in Xinjiang, China, the effects of three N application rates [75 kg ha−1 (N1), 150 kg ha−1 (N2), and 225 kg ha−1 (N3)] and three N application methods [the proportion of N applied at canopy rapid growth stage, taproot expansion stage, and sugar accumulation stage were (M1) 100%: 0%: 0%, (M2) 70%: 30%: 0%, and (M3) 50%: 30%: 20%] on the dry matter accumulation (DMA) and distribution, leaf senescence, yield, and agronomic N use efficiency (aNUE) of drip-irrigated sugar beet were explored. The results showed that N application (N1, N2, and N3 treatments) increased the shoot DMA by 27.7% (three-year average), 52.6%, and 83.1%, and the taproot DMA by 28.3%, 43.2%, and 61.6%, respectively (p &lt; 0.05), compared with CK (no N supply) treatment. The N application methods M2 and M3 increased the shoot DMA by 5.6% (three-year average) and 1.0% (p &gt; 0.05), respectively, and the taproot DMA by 7.2% and 3.6% (p &lt; 0.05), respectively, compared with M1. In addition, M2 could delay the end of shoot and taproot growth (te) and the occurrence of maximum growth rate (tm). In particular, the N3M2 treatment increased the leaf area index (LAI) by 20.4–75.9% (p &lt; 0.05) compared with other treatments by increasing the leaf area duration (LAD) and decreasing the leaf senescence rate (LSR). The taproot yield and sugar yield of N3M2 treatment reached the maximum at harvest time, but there was no significant difference in taproot yield and sugar yield between N3M2 treatment and N2M2 treatment. The aNUE in N2M2 treatment was the highest (p &lt; 0.05), which was 1.29–7.85 times higher than that of other treatments. Therefore, reducing the N application rate from 225 kg·ha−1 to 150 kg·ha−1 and applying 70% and 30% of 150 kg N ha−1 at the canopy rapid growth stage and the taproot expansion stage, respectively, could achieve the goal of increasing sugar beet yield and N use efficiency. This study will provide an important reference for the sustainable production of sugar beet under drip irrigation in Xinjiang, China.

Applying Boron by Fertigation or as a Foliar Fertilizer Is More Effective than Soil Applications in Northern Highbush Blueberry

Boron (B) is often deficient in many fruit crops, including blueberry (Vaccinium sp.). The objective of the present study was to evaluate different methods for applying B fertilizers to two commercial cultivars of northern highbush blueberry (V. corymbosum Earliblue and Aurora) in western Oregon, USA. Treatments included soil application of sodium tetraborate in early April (before bloom), foliar application of boric acid in late April (during bloom or petal fall), weekly fertigation with boric acid from April through July, and a control with no B. The plants were irrigated by drip, and the fertilizers were applied for two consecutive seasons at a total rate of 1.5 kg·ha−1 B per year. Each method of fertilizer application increased the concentration of B in the soil solution relative to the control, but fertigation was the only treatment that increased extractable soil B to the recommended level of 0.5 to 1.0 mg·kg−1 B. In terms of plant nutrition, foliar application of B was the most effective method for increasing the concentration of B in the leaves, roots, and fruit, followed by fertigation. Soil application of B, on the other hand, was relatively ineffective and, after 2 years, only increased the concentration of B in the leaves of ‘Earliblue’. Although leaf B levels were initially deficient at the site (&lt;30 ppm B), none of the B application methods had any effect on yield, berry weight, fruit firmness, or titratable acidity of the fruit in either cultivar. However, foliar applied B resulted in higher concentrations of soluble solids in the fruit than no B or soil applied B in ‘Earliblue’, whereas B fertigation resulted in higher concentrations of soluble solids than soil applied B in ‘Aurora’. On the basis of these results, applying B by fertigation or as a foliar spray is recommended over the use of soil applications of B fertilizer in northern highbush blueberry.

Regulation of photoassimilate transportation and nitrogen uptake to decrease greenhouse gas emissions in ratooning rice with higher economic return by optimized nitrogen supplies

Mechanized harvesting of the main crop rice, with low stubble height in rice ratooning is scaling up, especially in Southeast China with a higher population density and less cultivated land. Currently, the common nitrogen fertilization for ratoon rice is concentrated within 20 days before and after the harvest of the main crop. However, this fertilization pattern may not be suitable for low stubble regenerative rice due to its extended growth period, leading to diminished nitrogen utilization efficiency and heightened greenhouse gas emissions, particularly nitrous oxide (N2O) emissions. It is imperative to explore a nitrogen fertilizer management model for clean production of low stubble ratoon rice (RR). In this study, we examined the effects of nitrogen fertilizer application rates and methods (single or split application) on yield and greenhouse gas emissions during the regrowth season. We employed a multi-criteria assessment approach combined with field measurements, energy analysis, environmental assessment, and economic evaluation on ratoon rice under various nitrogen fertilizer treatments. The results showed that the ratoon rice produced the highest total energy output under 67.5 N+22.5 N (Fertilize with 67.5 kg nitrogen ha−1 and 22.5 kg nitrogen ha−1 3 days after main season rice harvesting and during the heading stage of ratoon rice) treatment compared to the 90 N+0 N (conventional fertilization, apply 90 kg nitrogen ha−1 fertilizer 3 days after harvesting at once) treatment. It was also found that reducing nitrogen application during the tillering stage reduced CH4 emissions, fertilization during the heading stage of the ratoon rice did not increase CH4 emissions, Since fertilization during the heading stage of ratoon rice did not lead to an increase in the partitioning of photoassimilates (photosynthetic product assimilates) to the rhizosphere soil, significant differences in sugar and acetic acid levels were not observed in the rhizosphere soil. As a result, no change was found in the expression of the methanogenic mcrA gene in the microbial community. The study also demonstrated that the 67.5 N+22.5 N treatment was able to promote the absorption of nitrogen nutrients, reduction in N2O emissions by 16.61%, subsequently increasing resource use efficiency, final yield and net ecosystem economic benefit by 5.96%, 7.19% and 5.57%, respectively, thereby decreasing carbon and nitrogen footprints by 6.64% and 3.50% compared with the 90 N+0 N treatment in the ratoon rice. These results suggest that a reasonable ratoon rice cultivation scheme is a promising farming system that can simultaneously improve resource use efficiency and economic profits, reduce greenhouse gas emissions and environmental footprint, while still maintaining the high productivity in ratoon rice.

Effects of Nitrogen Fertilizer Doses and Application Methods on the Yield of Syr Suluy Rice in the Kyzylorda Region

Effects of Nitrogen Fertilizer Doses and Application Methods on the Yield of Syr Suluy Rice in the Kyzylorda Region