Optimum Application Rate Research Articles

Optimum Application Rate of Nitrogen, Phosphorus, and Potassium Fertilizers for Kenaf (Hibiscus cannabinus L.) Yield and Soil Chemical Properties in a Reclaimed Paddy Soil: A Pot Experiment

Kenaf (Hibiscus cannabinus L.) has been considered one of the alternative crops for bioenergy production, potentially replacing fossil fuel. However, there are few studies available on systematically investigating kenaf growth characteristics and its fertilization conditions so far. Our study investigated its biomass productivity and soil properties at the different fertilization regimes including three major treatments (N, P2O5, and K2O) with four application levels [0%-50%-100% (as recommended), and 200%] in a reclaimed paddy soil during pot experiment under upland condition in 2021. The results showed the maximum of kenaf biomass productivity was observed when 158 kg ha-1 of N, 156 kg ha-1 of P2O5 and 102 kg ha-1 of K2O were applied, showing 62.6 g d.w pot-1, 64.1 g d.w pot-1, and 64.9 g d.w pot-1, respectively. Our study revealed that kenaf biomass mainly showed positive correlations with electrical conductivity (EC) and total N contents in soils, suggesting that these could be major growth limiting factors for kenaf production. Our study provides a better understanding for producing the maximum kenaf biomass, filling the gap on a promising nutrient management strategy for its optimum production in southern reclaimed paddy soils.The effect of kenaf biomass productivity at different inorganic fertilization regimes in a reclaimed paddy soil during the pot experiment.

Nitrogen Application Effect on Maize Yield, NH3, and N2O Emissions in Northeast China by Meta-Analysis

Ammonia volatilization (NH3) and nitrous oxide (N2O) emission are the main underliers of nitrogen loss in farmlands, which can decrease nitrogen use efficiency and trigger environmental problems regarding greenhouse effects. Previous studies have regional limitations and lack universal guiding significance, as they are primarily based on individual experiments related to the effects of applying nitrogen fertilizer on maize. In this study, we performed a meta-analysis on a regional scale to investigate the overall impact of nitrogen fertilizer application on maize yield, N2O, and NH3 in Northeast China. The database included 85 studies and 1147 pairs of experimental data that were analyzed. The results showed that applying nitrogen fertilizer significantly increased maize yield, N2O emissions, and NH3 volatilization effects, and the growth rates (E) were 50.64%, 64.39%, and 69.25%, respectively. In Northeast China, the average emission factors of N2O and NH3 were 0.72% and 8.21%, respectively. The optimum nitrogen application rate for maize in Northeast China was 205 kg ha−1, resulting in 8.37% nitrogen loss (through N2O and NH3). Soil texture, alkaline nitrogen (AN) content in the soil, mean annual precipitation (MAP), nitrogen application rate, and fertilizer type were the key influential factors affecting changes in maize yield and N loss (N2O and NH3). Yield-scaled N2O and NH3 were found to be the significant emission reduction parameters that ensured maize yield. However, there was a remarkable ‘seesaw effect’ between yield-scaled N2O and NH3 under the same natural conditions (MAP and soil texture). Therefore, human activities such as reducing N surplus in soil, and N fertilizer application rate, along with selecting suitable fertilizer types should be given more attention to reduce yield-scaled N2O and NH3. Moreover, minimizing NH3 and N2O dual emission should be the main objective for green agriculture in Northeast China, rather than over-emphasizing on single emission reduction.

Balancing quality and productivity of Apocynum venetum with N and P fertilizer management under drip irrigation in arid conditions of Northwest China

Although Apocynum venetum L. is a valuable native species in China for economic and industrial purposes, less studies have been conducted to determine the optimum fertilizer application rate for cultivating it. The leaves of A. venetum are used as traditional Chinese herbs and the fiber is referred to as “king of wild fiber’’ because of its anti-microbial and anti-UV features. It grows in poor soils but currently populations of wild A. venetum in China are decreasing rapidly. Developing cultivation techniques for endangered A. venetum to achieve sustainable long-term use of this plant resource has become urgent and important. The role of nutrient supply in increasing yield and quality is currently unknown. To maximize the productivity and economic value of A. venetum, a 3-yr nutrient trial was conducted under drip irrigation to evaluate optimal fertilizer application for producing high yield (dry leaves) and better quality. The effects of N/P combination (N0-0 kg/ha, N1-17.4 kg/ha, N2-34.8 kg/ha, and N3-52.2 kg/ha; P0-0 kg/ha, P1-28.6 kg/ha, P2-57.2 kg/ha, and P3-85.8 kg/ha) on plant growth, yield, as well as the quality of drip-fertilized A. venetum, in northwest China were also investigated. Principal component analysis (PCA) and membership function analysis were implemented to develop a comprehensive evaluation model of nutrient interactions to determine the best N/P fertilizer application scheme for simultaneous yield and quality improvement of A. venetum. Overall, fertilization promoted the growth of A. venetum. With increasing fertilizer application, the growth, leaf yield, and quality of A. venetum tended to increase and then decrease. The maximum leaf yield was achieved under T6 (N2P2) treatment that was increased by 213.1 %, 184.3 %, and 88.3 % compared with controls from 2018 to 2020, respectively. Under T6 as well, the best total flavonoid, rutin, and isoquercitrin contents were observed, which were increased by 52.17 %, 68.39 %, and 128.07 % on average for three years. Correlation analysis showed that agronomic traits (plant height, stem diameter, secondary branch, and reproductive branch number) were positively correlated with both yield (aboveground biomass, yield) and quality (rutin, isoquercitrin, and total flavonoids content). According to the comprehensive evaluation model, the optimum N/P fertilizer pairing combination was N2P2, which resulted in the best quality and highest yield of A. venetum. The current research determined the fertilizer application to cultivate A. venetum and elucidated the effects on productivity and quality. This study provides a foundation for developing cultivation practices of A. venetum and promoting its application.

Effects of Nitrogen Application in Recovery Period after Different High Temperature Stress on Plant Growth of Greenhouse Tomato at Flowering and Fruiting Stages

High temperatures have become a severe factor limiting growth and yield for tomatoes (Lycopersicon esculentum Mill.) due to unfavorable, above-optimum temperatures. Temperature and nitrogen application were the main regulatory factors in tomato plant cultivation. This research was undertaken to evaluate the effects of nitrogen application and high temperature on tomato morphology, dry matter accumulation and distribution, root vitality and nitrogen content of the above ground. Tomato variety “Jinfen No. 1” was planted and exposed to 4 day/night temperature levels (25 °C/15 °C as control CKT; 30 °C/20 °C, lightly high-temperature LHT; 35 °C/25 °C, moderate high-temperature MHT; 40 °C/30 °C, severe high temperature SHT) for 7 days after five nitrogen supply levels (N1–N5: 0, 1.3, 1.95, 2.6 and 3.75 g/plant, respectively; 2.6 g/plant is the recommended nitrogen-application rate, as control CKTN4). Within conditions, there was an extremely significant difference (p < 0.01) in all tomato plant parameters and an extremely significant interaction (p < 0.01) between high temperatures and nitrogen supply levels, except for plant height sampling on the 1st day in the recovery period. Dry matter accumulation decreased, and the accumulation rate slowed down. Dry matter accumulation under low nitrogen treatment was higher than in high nitrogen treatment. The proportion of dry matter in leaves decreased, the proportion of dry matter in stems increased and the difference in dry matter accumulation and proportion of dry matter between different nitrogen treatments decreased. Under LHT, the root activity of the tomato was increased under all nitrogen levels, while under MHT and SHT, high nitrogen and low nitrogen supply significantly inhibited root activity. Lightly high-temperature stress can increase root activity, and LHTN4 can increase by 5.15% compared with CKTN4. Appropriate nitrogen application can alleviate the damage caused by high-temperature stress on tomato plants and enhance the resistance of tomato plants, while excessive nitrogen application will aggravate the damage degree of tomato plants. In this study, the optimal nitrogen application rates under CKT-SHT treatment were 2.6, 2.6, 1.95 and 1.3 g/plant, respectively.

IMPACT OF Tithonia diversifolia AS GREEN MANURE AMENDMENT ON YIELD AND YIELD ATTRIBUTES OF MAIZE (Zea mays.)

Manures improve soil fertility and crop yield; however, the optimum rate and method of application are important. This experiment was conducted to determine the impact of different rates and modes of application of Tithonia diversifolia on the yield and yield component of two maize varieties. The trial was conducted at the Teaching and Research Farm of the, (federal university, Oye Ekiti, Nigeria during the 2020 and 2021 cropping seasons). The experiment was laid out in a factorial arrangement fitted into a randomized complete block design replicated 3 times. The trial comprised of two maize varieties (LNTP-W and SAUWUAZ), two methods of application of Tithonia diversifolia amendments (chopped and and unchopped). Grain yield and yield components were measured. The result showed that significant difference (P < 0.01) was observed among the maize varieties for number of seeds per cob, 100 seed weight and grain yield. Also the status of amendments showed significant (P < 0.01) impact on cob length while the quantity of the amendment also had significant (P < 0.01) impact on the number of rows per cob, number of seeds per cob, 100 seed weight and grain yield in both years. Significant (P < 0.01) interaction was observed between the maize varieties and quantity of amendments used. Also the status of the amendment x quantity had significant (P < 0.01) impact on the number of rows per cob. However, varieties x status x quantity showed significant impact on the number of seeds per row and number of seeds per cob in 2021.

Experimental Study of the Effect of Tack Coats on Interlayer Bond Strength of Pavement

The performance and lifetime of the flexible asphalt pavement are mainly dependent on the interfacial bond strength between layer courses. To enhance the bond between layers, adhesive materials, such as tack coats, are used. The tack coat itself is a bituminous material, which is applied on an existing relatively non-absorbent surface to ensure a strong bond between the old and newly paved layer. The primary objective of this study was to evaluate the effects of various types of tack coat materials on interlayer bond strength and to determine the optimal application rate for each type. The tack coat types used in this paper were RC-70, RC-250, and CSS-1h. Both laboratory-prepared and field-constructed hot mix asphalt concrete pavements using the tack coats were tested for the binding strength between the layers. A direct shear test was used for the testing. The results obtained from the study showed that the optimum application rate for RC-70 was 0.1 L/m2, and for RC-250, it was 0.2 L/m2, while the optimum application rate for CSS-1h was 0.1 L/m2. From the field test, the optimum application rate of the RC-250 tack coat was 0.1 L/m2.

Changes in canopy microclimate of faba bean under intercropping at controlled nitrogen levels and their correlation with crop yield.

The relationship between the microclimate of the intercropping faba bean canopy and yield, and its response to nitrogen application, was studied in the crop canopy to clarify that intercropping and nitrogen application changed the microclimate of the faba bean canopy and affected the yield. In field experiments in Eshan and Xundian, the growth index, light transmittance, interception rate of photosynthetic effective radiation, temperature, relative humidity, and yield of the faba bean were determined using three planting methods (wheat monoculture, faba bean monoculture, and wheat-faba bean intercropping) and four nitrogen application levels, N0 (0 kg/hm2 ), N1 (45 kg/hm2 ), N2 (90 kg/hm2 ), and N3 (180 kg/hm2 ). The results showed that the application of nitrogen improved the growth index of monoculture and intercropping broad beans significantly, reduced the canopy light transmittance and temperature significantly, and increased the interception rate and relative humidity of photosynthetic effective radiation significantly. Compared with N0, the yield of broad bean in both places was the highest in N1, which increased by 14% (Eshan) and 15% (Xundian). Multiple linear stepwise regression and path analysis showed that the decrease in canopy light transmittance during the faba bean pod-setting stage and the interception rate of photosynthetic effective radiation during pod-bulging stage, caused by excessive nitrogen application, were the main climatic and ecological factors limiting the increase in the intercropping faba bean yield in Eshan and Xundian respectively. The optimum nitrogen application rate recommended in production is 45kg/hm2 , to reduce the nitrogen application rate and maximize the productivity of the wheat and faba bean system. © 2023 Society of Chemical Industry.

Effect of Nitrogen Application Rate on Grain Yield, Dry Matter and Nitrogen Accumulation and Remobilization in a Winter Wheat-Fresh Maize Cropping System

Three-harvest in two years is a traditional farming system in the Jinzhong Basin of Shanxi Province of the eastern Loess Plateau in China. Recently, an innovative farming system of winter wheat-fresh maize with two-harvest per year, making full use of temperature and light resources, is proposed. However, there is little known of the optimal nitrogen application rate for the innovative farming system to increase crop yield and improve ecological environment. In current study, six nitrogen application rates were carried out, consisting of winter wheat/fresh maize season 0/0 kg·ha-1 (N0, Control), 75/75 kg·ha-1 (N75), 150/150 kg·ha-1 (N150), 225/225 kg·ha-1 (N225), 300/300 kg·ha-1 (N300) and 375/375 kg·ha-1 (N375). The grain yield, dry matter and nitrogen accumulation and remobilization were analyzed to determine the optimal nitrogen application rate in the winter wheat-fresh maize cropping system in the Jinzhong Basin. The results showed that in the winter wheat and fresh maize season, compared with the N0, N75 and N375 treatments, total dry matter accumulation at winter wheat maturity and fresh maize harvesting increased significantly by 82.9%-94.5% and 26.1%-197.1%, respectively, and dry matter remobilization in leaves and stem+sheath (+tassel) increased significantly under the N150 treatment. Total nitrogen accumulations under the N150, N225 and N300 treatments increased significantly by 58.2%-162.9% and 55.7%-301.7% compared with those under the N0 and N75 treatments, respectively. Nitrogen remobilization in the kernel and stem+sheath (+tassel) under the N150 treatment increased significantly compared with the N0 and N75 treatments. In addition, nitrogen partial factor productivity of winter wheat and fresh maize under the N75 and N150 treatments increased significantly by 36.7%-534.1% and 45.2%-390.4% compared with the other nitrogen treatments, respectively, and nitrogen uptake efficiency also increased significantly by 79.1%-321.4% and 58.3%-239.5%, respectively. The yield of winter wheat and fresh maize under the N225 treatment was the highest, which significantly increased by 54.1% and 71.6% compared with that under the N0 treatment, respectively. In summary, nitrogen application rates of 150-225/150-225 kg·ha-1can be potential recommended use amounts with higher crop yield and nitrogen use efficiency in winter wheat-fresh maize cropping system in the Jinzhong Basin.

Combinatorial Effect of Fertigation Rate and Scheduling on Tomato Performance under Naturally Ventilated Polyhouse in Indian Humid Sub-Tropics

Protected cultivation is a resource-efficient method of crop production, however, at the same time, it is resource intensive. An optimum rate and time of fertilizer application is required in order to maximize crop yield vis-à-vis resource use efficiency. However, these aspects are scarcely studied for tomato under low- and medium-tech greenhouses in Indian humid sub-tropics. In this regard, a two-year study was conducted to assess the effect of four NPK fertilization rates (i.e., 120, 100, 80, and 60% of the recommended dose of fertilizers, RDF) and three fertigation scheduling approaches—fertigation at different stages in different proportions of NPK, along with an additional treatment, i.e., farmers’ practice (soil-based application of recommended NPK) for tomatoes under a naturally ventilated polyhouse. The plant growth attributes, the tomato yield- and quality-related traits, the nutrient (NPK) accumulation by the plants, the water use efficiency (WUE), and economics were studied in response to different fertigation rates and scheduling approaches. These parameters were affected by both the rates of NPK fertilization and their time of application (scheduling) over the different growth stages. Among the different rates and time of fertigation, the recommended dose of fertilizer (100% RDF) (i.e., 300 kg N, 150 kg P2O5, and 150 kg K2O per ha and their scheduling as 15% N, 10% P2O5, and 10% K2O of RDF during 15–45 days after transplanting (P1); 40% N, 40% P2O5, and 40% K2O of RDF during 47–76 DAT (P2); 30% N, 40% P2O5, and 40% K2O of RDF during 77–107 DAT (P3); and 15% N, 10% P2O5, and 10% K2O of RDF during 108–138 DAT (P4)) was found to be the optimum for fruit yield, WUE, and economics of tomato under protected condition.

Advances and prospects of biochar in improving soil fertility, biochemical quality, and environmental applications

With the global food deficit increasing and rising climate change issues, there is a need to find green solutions to improve soil fertility and productivity while enhancing soil biochemical quality and reducing the ecological impact of agriculture. Biochar is a potentially cost-effective, carbonaceous resource with many agricultural and environmental applications. As a soil amendment, it improves soil physical and biochemical properties and increases soil fertility and productivity—particularly over the long-term—increasing soil aggregation, water retention, pH, and microbial activities, thus, improving overall soil quality, potentially helping to reduce chemical fertilizer needs over time. The extent of biochar’s impact on soil physiochemical properties varies depending on biochar source, type, size, inherent soil characteristics, cropping system, etc. Moreover, biochar has significant potential in soil and water remediation, especially through its unique adsorption and chemical properties capable to capture and immobilize pollutants such as metal(loid)s, organic pollutants, and hazardous emerging contaminants such as microplastics. Further, biochar has also emerged as a key strategic, cost-effective material to tackle global issues such as climate change mitigation, reducing the net greenhouse gas emission to minimize global warming potential. However, a knowledge gap remains as to understanding the long-term persistence of biochar on agroecosystem, optimal biochar application rate for the diversity of biochar-soil-crop-environmental conditions, interaction of biochar with inherent soil carbon stock, specific mechanisms of biochar’s effect on soil biotic properties, quantification of carbon sequestration, greenhouse gas emissions, synergy or potential antagonistic effects with other carbon sources such as compost, manure, residues, etc., its modification for environmental applications and associated environmental and human risks over long-term. Further research is needed to evaluate the long-term impacts of types and sizes of biochar on overall soil quality to recommend suitable application practices based on soil management and cropping system. Also, its environmental applications need to be finetuned for wider and target specific applications to tackle pressing environmental issues such as soil and water pollution.

Effects of concentration-dependent graphene on maize seedling development and soil nutrients

The long-term use of chemical fertilizers to maintain agricultural production has had various harmful effects on farmland and has greatly impacted agriculture's sustainable expansion. Graphene, a unique and effective nanomaterial, is used in plant-soil applications to improve plant nutrient uptake, reduce chemical fertilizer pollution by relieving inadequate soil nutrient conditions and enhance soil absorption of nutrient components. We investigated the effects of graphene amendment on nutrient content, maize growth, and soil physicochemical parameters. In each treatment, 5 graphene concentration gradients (0, 25, 50, 100, and 150 g kg−1) were applied in 2 different types (single-layer and few-layers, SL and FL). Soil aggregates, soil accessible nutrients, soil enzyme activity, plant nutrients, plant height, stem diameter, dry weight, and fresh weight were all measured throughout the maize growth to the V3 stage. Compared to the control (0 g kg−1), we found that graphene increased the percentage of large agglomerates (0.25–10 mm) in the soil and significantly increased the geometric mean diameter (GMD) and mean weight diameter (MWD) values of > 0.25 mm water-stable agglomerates as the increase of concentration. Soil available nutrient content (AN, AP, and AK) increased, peaking at 150 g kg−1. Graphene boosted nutrient absorption by maize plants, and aboveground total nitrogen (TN), total phosphorus (TP), and total potassium (TK) contents rose with the increasing application, which raised aboveground fresh weight, dry weight, plant height, and stalk thickness. The findings above confirmed our prediction that adding graphene to the soil may improve maize plant biomass by enhancing soil fertility and improving the soil environment. Given the higher manufacturing cost of single-layer graphene and the greater effect of few-layer graphene on soil and maize plants at the same concentration, single-layer graphene and few-layer graphene at a concentration of 50 g kg−1 were the optimal application rates.

Responses of crop production and soil health to chemical nitrogen fertilization in a maize-wheat rotation system

Chemical nitrogen (N) fertilizer is generally applied at high rates to maximize crop yields and also many non-grain farmlands are being converted into grain production to ensure grain production safety in China now. To test the effects of chemical N on crop production and soil health, a 3-year trial with urea and controlled-release fertilizer was conducted in a maize (Zea mays L.)-wheat (Triticum aestivum L.) system shifted from vegetable farmland by evaluating the effects of N fertilization on crop yields, typical soil properties, and soil bacterial community using 16S rRNA gene sequencing. The maximum crop yield and aboveground N uptake efficiency was achieved at 150 kg N ha-1 for wheat and 200 kg N ha-1 for maize. After three cropping seasons, the soil N properties were notably altered. For each kg of N applied, soil pH decreased at a rate of 0.0004–0.0012 pH units. The soil total N (TN) and total carbon (TC) content reached a higher stability at certain cumulative N application rates. However, the C/N ratio linearly decreased as N rate increased. Consequently, N application significantly decreased soil bacterial diversity owing to the decrease of α-diversity indexes of Shannon and Pielou_e. At the phylum level, chemical N application significantly depleted members of Acidobacteria, Chloroflexi and Nitrospirae, but the growth of Actinobacteria, Gemmatimonadetes, Firmicutes and Patescibacteria were improved. Compared with urea, the controlled-release fertilizer did not significantly change crop yields, soil bacterial diversity, soil TN and TC content. Overall, our results indicated that chemical N promoted crop yields at optimum application rates, but excessive N application could result in a decline in soil health, specifically accelerated soil acidification, a decrease in soil bacterial diversity, and soil C and N imbalance.

Statistical Study of the Effectiveness of Surface Application of Graphene Oxide as a Coating for Concrete Protection

Improving the protection of concrete by applying graphene oxide (GO) as a surface treatment has become the objective of the present study. This study focuses on performing a statistical analysis to study different levels of GO application as an exterior coating, thus observing the effectiveness of the coating and the optimization of the treatment material for concrete protection. Four tests were performed to define concrete durability, such as pressurized water penetration, capillary absorption, freeze-thaw resistance and carbonation resistance. The results showed an increase in concrete durability with any level of GO application on the surface, considering that the optimum amount of application for water impermeability and freeze-thaw resistance is 26.2 µg/cm2, since it was possible to reduce pressurized water penetration by 45%, capillary water absorption by 57% and freeze-thaw detachment by 25%. However, the optimum application rate for carbonation resistance is 52.4 µg/cm2, reducing carbonation by almost 60%. In conclusion, if the concrete is going to be exposed to less aggressive environments, the application of a mild surface coating of GO is sufficient for its protection, and if the concrete is going to be exposed to more aggressive environments, it is necessary to increase the amount of GO. The performance of GO as a coating significantly increased the degree of protection of the concrete, increasing its service life and proving to be a promising treatment for concrete surface protection.

Application of optimal solution concentration in mineral fertilizer suspension foliar feeding in winter wheat

Taking into account plant biological properties, soil properties, soil-climatic conditions, and fertilizer properties, the development of the optimal rate, duration, and methods of application of suspensions made from mineral fertilizers, the optimization of the soil nutrient environment, the formation of the necessary chemical composition in the plant, and scientific research aimed at managing plant nutrition, special attention is paid. In Uzbekistan, scientific research aimed at evaluating the effective use of mineral fertilizers in increasing the yield of agricultural crops, including wheat, is being conducted, and certain results are being achieved. It is critical to develop an optimal system of using mineral fertilizers to ensure the cultivation of high-quality grain crops from autumn wheat varieties in the irrigated typical gray soils of the Tashkent province, as well as to determine the nutrient environment formed in the soil during specific periods of autumn wheat development phases and the amount and ratio of nutrients in the plant. Fertilizer is an effective and fast-acting factor that increases the quality of the crop. Therefore, it is important to develop the optimal norm for using a suspension of mineral fertilizers in foliar feeding, taking into account the characteristics of the soil and variety, to grow a high-quality grain crop from wheat, as well as to study the effect of these norms on the growth development, seedling thickness, grain yield, and quality of autumn wheat.

Капельное орошение молодых плантаций виноградников в условиях Республики Крым

Purpose: to determine elements of irrigation technology for young vineyard plantations using the drip irrigation method on various types of soil in the Republic of Crimea and test them under the conditions of this region. Materials and methods. The research was carried out in the village of Pavlovka, Belogorsky district of the Republic of Crimea. The establishment of field experiments and observations were carried out using generally accepted methods for setting up and conducting field experiments. Results. As a result of the research, the water-physical properties of soils of the Republic of Crimea were analyzed and rational elements of the technology for irrigating young vineyard plantations using drip irrigation on various types of soils (limits of optimal soil moisture, dripper consumption, wetted depth, irrigation period and water application rate) were calculated. When calculating the irrigation regime for the drip irrigation method, it is necessary to take into account the wetted layer depth, the physical properties of soil, the planting pattern, the moisture contour shape, the dripper flow rate and pre-irrigation soil moisture. The elements of irrigation technology for young vineyard plantations vary significantly, for example, the recommended flow rate of drippers varies from 2–4 l/h on chernozems to 6–8 l/h on light chestnut soils and steppe solonetzes, while the duration of irrigation varies from 2–3 h on light chestnut soils up to 6–9 h on ordinary chernozems. Conclusions. When testing the results, it was found that the drip irrigation method has a positive effect on the survival rate of table grape cuttings. On average, this indicator for varieties was 98.8%. For soil and climatic conditions of the Republic of Crimea, the varieties Sport, Podarok to Irina, Baikonur and Zabava turned out to be the most responsive in terms of their morphological characteristics. During the growing season of the first year young table grapes (in a medium-dry year), 16 irrigations of 30 cubic m/ha with an irrigation rate of 480 cubic m/ha were carried out, while the total water consumption excluding the use of moisture from soil was 3740 cubic m/ha.

Optimal nitrogen fertilizer application rates for second-generation cranberry hybrids

Optimal nitrogen fertilizer application rates for second-generation cranberry hybrids

Формализация параметров модуля фертигации в системах капельного орошения

Purpose: to formalize the parameters on which the choice of optimal fertilizer application rates depends with fuzzy sets for constructing a fuzzy model and a control system for the fertigation module. Materials and methods. The use of Soft Computing methods is required by the need to represent the input variables values in the form of fuzzy sets, with further structural and parametric identification of a fuzzy model for controlling the concentration of nutrients in the solution. This will enable to compile fuzzy knowledge bases in the form of “IF – THEN” rules and, using fuzzy logic methods, to determine the well-defined values of output variables: the necessary application rates of nitrogen, phosphorus and potassium with irrigation water. Results. As input variables, the parameters on which the choice of optimal fertilizer rates depends are determined. At the output of the model, three variables determining the norms of nitrogen, phosphorus and potassium of the nutrient solution are used. For each of the selected input and output variables, the measurement ranges and the linguistic term values are selected and membership functions are constructed. Conclusions. The conducted formalization of input and output values will make it possible to build the structure of the fertigation module control model, to form fuzzy rule bases and to implement fuzzy logical inference according to the Mamdani algorithm. This will allow defuzzification of the output variables using the center of gravity method in order to obtain a clear numerical value at the output. It is also possible to carry out parametric identification of the obtained model from the training sample by adjusting the membership functions parameters of the. Thanks to the use of IoT technologies, it will be possible to carry out external control and, if necessary, manual control of the fertigation system.

Biochar: An Eco-friendly Approach for the Alleviation of Nitrate Leaching and Augmentation of Soil Health

Our study investigated the efficacy of barberry biochar in reducing nitrate leaching in arid and semi-arid area. The experiment was conducted in factorial design investigating the effect of two biochar particle sizes (less than 1mm and more than 2.8 mm) and three biochar amounts (1%, 2%, and 3% by mass ratio) on nitrate leaching in soil. Our findings revealed significant reductions in nitrate leaching upon the application of barberry biochar. The experimental treatments had a significant effect on nitrate concentration in leached water in both sampling stages. Although the initial sampling indicated non-significant variances between particle size, clear statistical differences emerged in the second sampling. The smaller biochar particle sizes (less than 1 mm) recorded greater reductions by 76.3% in nitrate leaching compared to larger ones (exceeding 2.8 mm) that resulted in 66.2% reduction. Our results indicated that a 1% weight of biochar produced the lowest leaching rate, with reductions of 79.7% in the first sampling and 82.6% in the second sampling. Finer biochar particle sizes (< 1mm) were the most effective at reducing nitrate leaching, which achieved to an 80.9% reduction. Overall, barberry biochar shows potential in mitigating nitrate pollution, enhancing soil quality, and promoting agricultural sustainability. It is important to consider the optimal biochar application rate and particle size to maximize its effectiveness in reducing nitrate leaching while minimizing any potential negative impacts on crop yield. Further research is required to optimize biochar application rates, particle sizes, and long-term effects in diverse agricultural systems. Implementing biochar as a soil amendment holds promise in improving soil health, water quality, and overall sustainability.

Effect of Nitrogen in Combination with Different Levels of Sulfur on Wheat Growth and Yield.

As macronutrients, management of nitrogen (N) and sulfur (S) is prime in importance when wheat is cultivated. Both have a significant impact on the improvement of growth and yield attributes. In addition, S and N also play an imperative role in the enhancement of seed protein contents. However, the need of the time is the selection of their optimum application rate for the achievement of maximum wheat productivity. That is why the current study was planned to examine the impact of variable application rates of S and N on wheat. There are 12 treatments, i.e., control (no nitrogen (0N) + no sulfur (0S)), 40 kg/ha N (40N + 0S), 80 kg/ha N (80N + 0S), 120 kg/ha N (120N + 0S), 30 kg/ha sulfur (30S), 40N + 30S, 80N + 30S, 120N + 30S, 60 kg/ha sulfur (60S), 40N + 60S, 80N + 60S, and 120N + 60S, applied in three replications. The results showed that plant height, grains/spike, spike/m2, and 1000 grain weight were significantly improved by the addition of 120N + 60S. A significant enhancement of grain N contents, N uptake, and protein contents of wheat validated the efficient role of 120N + 60S over 0N and 0S. In conclusion, 120N + 60S is a better treatment for the achievement of maximum wheat yield. More investigations under variable soil textures and climatic conditions are suggested under different climates to declare 120N + 60S as the best amendment for wheat growth and yield improvement.

Deteriorating Harmful Effects of Drought in Cucumber by Spraying Glycinebetaine

In order to alleviate the shortage of irrigation water in dry regions, refining water use efficiency (WUE) is a key issue in sustainable productivity. Furthermore, glycinebetaine (GlyBet) is a vital osmoprotectant produced in crops for improving drought tolerance; however, little is known about its role in improving plant WUE under field conditions in non-accumulating plants such as cucumber. In order to elucidate the effectiveness of GlyBet concentrations (0, 2000, 4000, and 6000 mg/L) in mitigating the deleterious effects of drought (e.g., well-watered (1250 m3/fed), moderate drought (950 m3/fed), and severe drought (650 m3/fed)), field experiments were conducted at Elmia village, Dakahlia, Egypt in the 2020 and 2021 seasons on vegetative growth, some physiological attributes, as well as yield and quality. Drought considerably decreased vegetative growth, yield and its components, leaf relative water content, and photosynthetic pigment concentrations compared with well-watered plants while increasing electrolyte leakage. The most harmful causes were severe drought. However, exogenous spraying with GlyBet substantially boosted the mentioned attributes, but reduced electrolyte leakage within well-watering. Commonly 6000 mg/L contributed to the maximum growth and productivity, preserving cucumber plant water status above other concentrations or untreated plants. Under extreme drought, the application of 6000 mg/L GlyBet had a beneficial effect on moderating the damage of water deficit on cucumber plant growth and productivity. Overall, using GlyBet as a cost-effective and eco-friendly biostimulant six times (10, 20, 30, 40, 50, and 60 days from sowing) has the potential to mitigate drought damage while also increasing yield; however, more research is needed to determine the optimal rate and timing of application.