Potash Research Articles

Effects of different fertilization patterns on soil improvement and vegetation restoration of desertified grassland in northwest Liaoning Province, China

Improving soil fertility is one of the key approaches for ecological restoration of the wind-sand area in northwest Liaoning Province. Taking wind-sand area in northwest Liaoning Province as test object, we conducted a fertilization experiment with treatments of inorganic fertilizer (nitrogen, phosphorus and potassium fertilizers), organic fertilizer, combined application of organic and inorganic fertilizers, and organic fertilizer combined with a biologically organic matrix (γ-polyglutamic acid), and no fertilizer as control. We measured soil organic matter content and extractable cations concentrations, vegetation coverage, and biomass under different fertilization treatments and determine the suitable fertilization mode. The results showed that compared to the control, inorganic fertilizer rapidly increased vegetation coverage and biomass, but high levels of inorganic fertilizer (150 kg N·hm-2) led to soil acidification and Ca2+ leaching. Organic fertilizer increased soil organic matter content, exchangeable K+, Ca2+, and Mg2+ contents, as well as coverage and biomass vegetation, especially combined with γ-polyglutamic acid. Overall, the combination of low levels of inorganic fertilizer (50 kg N·hm-2) and moderate levels of organic fertilizer (30000 kg·hm-2) was the best fertilization practice for the rapid and stable restoration of grassland in wind-sand area. Moreover, the extra addition of γ-polyglutamic acid (60 kg·hm-2)could effectively improve soil fertility.

Production and postharvest quality of <i>Passiflora edulis</i> Sims under brackish water and potassium doses

<abstract> <p>The aim of this research was to assess the yield and postharvest characteristics of 'BRS Sol do Cerrado' sour passion fruits based on irrigation with varying levels of saline water and potassium fertilization. The study was conducted under field conditions at an experimental farm in São Domingos, Paraíba, Brazil. A randomized block design was implemented in a 5 × 4 factorial arrangement, with five levels of electrical conductivity of water (ECw): 0.3, 1.1, 1.9, 2.7, and 3.5 dS m<sup>−1</sup>, and four potassium doses (KD): 60, 80,100, and 120% of the recommended amount, with 3 replications. The potassium dose equivalent to 120% of the recommended dose in combination with low-salinity water resulted in the highest fresh mass accumulation in the sour passion fruit. Water electrical conductivity up to 2.7 dS m<sup>−1</sup>, along with the lowest recommended KD, led to increased levels of soluble solids and ascorbic acid in the sour passion fruit. Irrigation with water of 3.5 dS m<sup>−1</sup> and using 80 to 100% of the recommended KD enhanced the total sugar content in the sour passion fruit. On the other hand, irrigation with water of 3.5 dS m<sup>−1</sup> combined with 60% of the recommended KD resulted in a higher pulp yield in the 'BRS Sol do Cerrado' sour passion fruit 160 days post-transplantation. Adjustments in potassium fertilization management at different irrigation water salinity levels played a crucial role in maintaining both the production and quality of the sour passion fruit.</p> </abstract>

NPK fertilization modulates enzyme activity and mitigates the impacts of salinity on West Indian cherry.

Salt stress causes several physiological and biochemical disorders and impairs plant growth. However, adequate fertilization can improve the nutritional status and may reduce significantly the harmful effects caused by salt stress. From this perspective, this study aimed to evaluate the impact of different combinations of nitrogen, phosphorus and potassium fertilization on the antioxidant activity and accumulation of organic and inorganic solutes in West Indian cherry leaves, in the second year of production. The experimental design was in randomized blocks, with treatments distributed in a 10 × 2 factorial arrangement corresponding to ten fertilization combinations (FC) of NPK (FC1: 80-100-100%, FC2:100-100-100%, FC3:120-100-100%, FC4:140-100-100%, FC5:100-80-100%, FC6:100-120-100%, FC7:100-140-100%, FC8:100-100-80%, FC9:100-100-120%, and FC10:100-100-140% of the recommendation) and two levels of electrical conductivity of irrigation water (ECw) (0.6 and 4.0 dS m-1), with three replications. The multivariate analysis showed that irrigation with water of different electrical conductivities (0.6 and 4.0 dS m-1) resulted in different responses concerning the enzyme activity, production of organic compounds, and accumulation of inorganic solutes in the leaves. Under irrigation with low salinity water, there was greater accumulation of K+, soluble carbohydrates, and proline, and lower activity of antioxidative enzymes, especially SOD and APX. Under high salinity water, greater enzyme activity and higher concentrations of Na+ and Cl- were observed. The results indicate that the response of West Indian cherry to salinity was more towards redox homeostasis than osmotic homeostasis through the accumulation of compatible solutes. Fertilization combination FC5 (100-80-100% corresponding to 200, 24 and 80 g plant-1 of NPK) modulates the enzyme activity of SOD and APX attenuating the impacts of salinity, being an efficient combination to preserve redox homeostasis in West Indian cherry plants grown under salt stress.

Composição mineral de maracujazeiro-azedo cultivado sob irrigação com águas salinas e adubação potássica

ABSTRACT Salt stress is one of the main abiotic factors responsible for limiting agricultural production worldwide, especially in regions with a semi-arid climate, where climatic conditions intensify the effect of salts on plants. The objective of this study was to evaluate the mineral composition of sour passion fruit plants grown under irrigation with saline water and potassium fertilization in a semi-arid region of Brazil. The experiment was carried out under field conditions in São Domingos, PB, Brazil. A randomized block design was adopted, in a 5 × 4 factorial scheme, with five levels of electrical conductivity of irrigation water - ECw (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1) and four potassium doses - KD (60, 80, 100 and 120% of the K2O recommendation) with 3 replicates. There was an increase in sodium and chloride contents in the stem and leaves of sour passion fruit plants with the increase in ECw levels. Fertilization with 120% of the K2O recommendation associated with irrigation using water with EC of up to 1.1 and 1.6 dS m-1 increased potassium content in the stem and leaves and leaf nitrogen content, respectively, in ‘BRS Sol do Cerrado’ sour passion fruit plants. Fertilization with 60% of the K2O recommendation increased phosphorus content in the leaves of sour passion fruit plants under water salinity of up to 2.2 dS m-1. In the leaves, nutrient contents varied according to the order of concentration N>Cl>P>Na>K, while in the stem the order was N>Cl>P>Na>K, at 160 days after transplanting.

Interação nitrogênio e potássio em latossolo sob cultivo de trigo BRS 394

ABSTRACT Potassium and nitrogen are essential nutrients and their uptake and distribution within plants must be coordinated for optimum growth and development. We evaluated the interaction between nitrogen and potassium fertilization on the development of BRS 394 wheat, and the nitrate and ammonium levels in Oxisol soils. A 52 factorial design was used in a greenhouse experiment, with four replicates in randomized blocks, corresponding to five doses of nitrogen (0, 70, 140, 210, and 280 mg dm-3) and five doses of potassium (0, 50, 100, 150, and 200 mg dm-3). The variables analyzed were shoot dry mass; chlorophyll index; nitrate reductase; nitrogen, potassium, and protein concentrations in the leaves; and nitrate and ammonium levels in the soil. There was an interaction between nitrogen and potassium doses on the chlorophyll index, with nitrogen doses between 152.67 and 163.53 mg dm-3 and potassium of 191.50 mg dm-3 providing the highest chlorophyll index. The other variables were influenced separately by the nitrogen dose. The highest nitrate reductase enzyme activity was 1.30 µmol NO h-1 g-1 Fresh Matter, which was reached at a nitrogen dose of 95 mg dm-3. Shoot dry mass, concentrations of nitrogen and total protein in the leaves, and concentrations of nitrate and ammonium in the soil were adjusted to the linear regression model as a function of nitrogen fertilization. The dose of nitrogen that promoted the best development of BRS 394 wheat and the highest concentrations of nitrate and ammonium in Oxysol soils was 280 mg dm-3.

Estresse salino e adubação potássica no desempenho agronômico da cultura do amendoim

ABSTRACT In semi-arid regions, the use of brackish water for irrigation can reduce crop yields. However, the use of mineral fertilizer has been tested to mitigate salt stress. In this context, the objective was to evaluate the effect of salt stress at different phenological stages on the yield of peanut under potassium fertilization. The experiment was carried out from August to November 2021, in the experimental area of the Universidade da Integração da Lusofonia Afro-Brasileira (UNILAB), Redenção, Ceará, Brazil. The experimental design was completely randomized (CRD), in a 6 × 3 factorial scheme, with 6 replicates. Six strategies of irrigation with brackish water were applied from the following stages: vegetative (S1); flowering (S2); gynophore appearance (S3); pod formation (S4); fruiting (S5) and without salt stress (S6), and three doses of potassium: 0, 50 and 100% of the recommended dose. The use of brackish water in the vegetative stage led to lower pod length, pod mass, number of pods, number of marketable pods and yield. The dose corresponding to 100% of the recommended potassium dose mitigated salt stress in the pod formation and flowering stages, promoting a greater number of marketable pods, number of non-marketable pods, total number of pods and pod mass. The use of water with lower salinity throughout the cycle promoted greater pod mass, number of marketable pods and yield.

Impact of "3414" fertilization on the yield and quality of greenhouse tomatoes.

This study aimed to explore the effects of different nitrogen, phosphorus, and potassium ratios on the yield and nutritional quality of greenhouse tomatoes under a water and fertilizer integration model. Greenhouse tomatoes were used as the research object, and the "3414" fertilizer trial design was employed to assess tomato growth, yield, quality, and soil indicators across various treatment combinations. The goal was to determine the optimal fertilization scheme and recommend appropriate fertilizer quantities for tomato cultivation and production. The results revealed that different fertilizer ratios significantly affected both the quality and yield of tomatoes. Overall, the tomato yield tended to increase with higher fertilization amounts, with potassium exhibiting the most pronounced effect on yield increase, followed by phosphorus and nitrogen. The comprehensive analysis of principal components indicated that the N2P2K1 treatment yielded the highest nutritional quality and yield. Therefore, the best fertilization combination identified in this study consisted of nitrogen fertilizer at 197.28 kg hm-2, phosphorus fertilizer at 88.75 kg hm-2, and potassium fertilizer at 229.80 kg hm-2. These findings provided the scientific basis for optimizing fertilization practices in greenhouse tomato cultivation and production in the Jilin Province.

Estimating thresholds of nitrogen, phosphorus and potassium fertilizer rates for rice cropping systems in China.

Determining the fertilization rate plays a pivotal role in agronomic practices as they directly impact yield targets, soil fertility, and environmental risks. In this study, we proposed a method that utilizes allowed ranges of partial nutrient balance and yield to estimate the threshold of nitrogen (N), phosphorus (P), and potassium (K) fertilizer applied to rice (Oryza sativa L.) fields in China. Based on a dataset of 6792 observations from rice fields, we determined the minimum and maximum rates of N, P and K suggested for single (mono-season rice), middle (summer-season rice rotated with winter-season upland crop), early and late (double-season rice cropping system) rice, ranging between 114-146 and 220-292 kg N ha-1 per season, 56-74 and 112-149 kg P2O5 ha-1 per season, and 170-230 and 329-347 kg K2O ha-1 per season, respectively. These values serve as the lower and upper fertilization thresholds, guiding yield goals and environmental protection. Furthermore, if rice straw is returned to fields, the demand for K fertilizer can theoretically decrease by 183 kg K2O ha-1, with corresponding decreases of 50 kg N ha-1 and 26 kg P2O5 ha-1, respectively. A recommended fertilization approach, excluding returned straw nutrients from the upper fertilization thresholds, suggested average application rates of 194 kg N ha-1, 105 kg P2O5 ha-1, and 157 kg K2O ha-1, which align well with the nutrient requirements of rice. Additionally, substituting organic N for chemical N is an effective approach to conserve chemical fertilizer N, potentially reducing chemical N usage by 20%-40%. Utilizing slow-release N is also a favorable option to enhance N use efficiency and optimize N balance. This study offers valuable insights into the development of fertilization restriction indicators, aiming to achieve a delicate balance between environmental impact and agricultural productivity through the adoption of balanced fertilization rates and utilization of organic residues.

Combinations of nitrogen and potassium fertilization in the cultivation of cotton genotypes

Combinations of nitrogen and potassium fertilization in the cultivation of cotton genotypes

Estratégias de irrigação com água salobra no cultivo da abobrinha italiana sob adubação potássica

ABSTRACT Zucchini may present different responses to the presence of salts in its phenological phases, and the supply of potassium can interfere with assimilate allocation dynamics, maximizing production. In this context, the aim of this study was to evaluate the effect of brackish water irrigation strategies at different phenological stages under potassium fertilization on the yield and quality of italian zucchini fruits. A completely randomized design was adopted in a 4 x 3 factorial scheme, with the application of different irrigation strategies (S1, S2, S3 and S4) based on crop phenology using two electrical conductivities (ECw) (W1: 0.3 dS/m; W2: 2.6 dS/m). (S1= W1 throughout the crop cycle; S2= W1 up to flowering and early fruiting, and W2 during the full fruiting and harvesting phases; S3= W2 during flowering and early fruiting, and W1 during full fruiting and harvesting; S4= W1 up to flowering and early fruiting, W2 during the full fruiting phase, and W1 during harvesting), with three potassium doses (K1= 0, K2= 7.5, and K3= 15 g/plant), and four replications. Saline stress at any stage reduces fruit quality, in addition to resulting in lower productivity and water use efficiency. Doses of 50 (K2) and 100% (K3) potassium provided lower productivity and water use efficiency. Further analyses and research are required to determine the ideal dose for crops under similar conditions of this study.

Precision farming practices with data-driven analysis and machine learning-based crop and fertiliser recommendation system

Agriculture forms a major occupation in countries like India. More than 75% people rely on farming for their daily wages. Food security on a global scale is mostly dependent on agriculture. Hence, achieving good yield in the crops grown by farmers is the major concern. Various environmental factors have a significant impact on the crop yield. One such component that contributes majorly to the crop yield is soil. Due to urbanization and enhanced industrialization, the agricultural soil is getting contaminated, losing fertility, and hindering the crop yield. One exciting new way to maximise crop yields while decreasing input costs is precision farming, which makes use of machine learning (ML) and the IoT. Machine Learning (ML) is employed for agricultural data analysis. The goal of this research is to optimise agricultural practices by presenting an integrated crop and fertiliser recommendation system. The proposed ML based model “Precision Agriculture” aims at predicting the suitable crops that can be grown based on the class which the soil sample belongs to and suggests the fertilizers that can be used to further enhance the fertility of soil. Using proposed model, farmers can make decisions on which crop to grow based on the soil classification and decide upon the nitrogen–phosphorous– potassium (NPK) fertilizers ratio that can be used. Comparison of the SVM algorithm with Naive Bayes, and LSTM has shown that SVM performed with a higher accuracy. Decision support tools that integrate AI and domain knowledge are provided by the study, which is a substantial contribution to precision agriculture.

Desenvolvimento e produtividade de gergelim (cultivar k3) em latossolo amarelo em função da adubação potássica

ABSTRACT Sesame (Sesamum indicum L.) is an oilseed crop species valued for its nutritional properties. Sesame production has been a strategic alternative for expanding agricultural diversification in Mato Grosso, Brazil. In this context, the objective of this study was to assess growth and seed yield of sesame plants (cultivar K3) grown in a Typic Hapludox soil under potassium (K) fertilizer application. The experiment was conducted in a randomized block design with four replications, using a 6×4 factorial arrangement consisting of six K2O rates (0, 30, 50, 70, 90, and 120 kg ha-1) and four application times (0, 20, 30, and 40 days after sowing). Agronomic parameters were evaluated, including plant height, first capsule height, numbers of branches and capsules per plant, capsule weight, 1000-seed weight, and seed yield. Soil samples were chemically analyzed after harvest. Individual factors (K2O rates and application times) and the interaction between factors had no significant effects on plant height, first capsule height, number of branches per plant, and capsule and 1000-seed weights. The timing of fertilizer application did not significantly affect plant growth and seed yield. However, K fertilizer application increased soil K contents, number of capsules per plant, and seed yield. The highest seed yield was found for the K2O rate of 90 kg ha-1.

Late quaternary morpho-stratigraphic record of diapir rise in the Cardona salt extrusion, NE Spain. Halokinetic sequences, raised terraces and uplift rates

Active diapirism has received very limited attention from the geomorphological and Quaternary Science perspective, despite the role played by this ground deformation process in the development of landforms and sedimentary environments, and the important practical implications associated with mobile salt structures (e,g., mining, hydrocarbon production, geostorage). The Cardona salt extrusion (NE Spain) was initiated in late Quaternary times from the post-shortening unroofing of the crest of a salt anticline by the entrenchment of the transverse Cardener River. Detailed mapping, outcrop analysis, geophysical data and trenching indicate that the diapir-flanking deposits show halokinetic complexes comprising two types of morpho-stratigraphic units: (1) an older flap of coarse-grained drapefolded colluvial deposits; and (2) younger lacustrine and fluvial deposits in peripheral depressions confined between the upturned colluvial flaps and the country rock slope. These synkinematic units record an overall relief inversion and correspond to the so-called wedge and hook halokinetic sequences, recording ratios between diapir rise rate and sedimentation rate lower and greater than 1, respectively. The radiocarbon ages obtained from several raised late Holocene strath terraces carved in the salt indicate uplift rates within the range of 36.5–12.1 mm/yr, consistent with geodetic data. The spatial variability of the uplift rates can be related to increasing flow rates towards the axis of the salt wall and potential along-strike variations. The relatively high diapir rise rates observed at Cardona diapir, unaffected by contractional displacement loading (tectonic squeezing), is attributed to the youthful stage of the salt extrusion and the low dynamic viscosity of the Cardona Saline Formation, with a low proportion of impurities and a significant amount of potash salts.

Rice (Oryza sativa L.) yield and potassium use efficiency as affected by potassium fertilizer sources

Rice (Oryza sativa L.) yield and potassium use efficiency as affected by potassium fertilizer sources

Fertilizer management practices in potato cultivation: a baseline study for the introduction of GE potato in Bangladesh.

Genetically engineered (GE) crops have the potential to contribute to agricultural sustainability, food security, and nutritional enrichment. However, these crops cannot be released for commercial cultivation without undergoing environmental risk assessments (ERA), thus biosafety evaluation. ERA assessments are performed comparatively with their natural non-GE counterparts. As Bangladesh is progressing with GE potato research, the present study aims to collect baseline information on non-GE potato cultivation with an emphasis on current agronomic practices focusing on fertilizer management and farmers' knowledge base. The survey had three parts, including information on the farmers, information on potato cultivation practices, especially fertilizer use, and lastly, the farmer's view on GE potato. From 2020 to 2021, data were collected through interviews with experienced growers in four potato-growing regions, the Central and Mid-East, North-West, Mid-West, and South-East regions (n = 1757) of the country. The study revealed that farmers of all regions used more than the recommended amounts of fertilizer; for instance, 67.1% more nitrogen fertilizer was applied as an extra dose during potato cultivation in Munshiganj (Central and Mid-East) than in the Dinajpur region (North-West). This overuse of nitrogen fertilizer can enhance plant vigor but makes the plants more susceptible to insect attraction and allows pests easier access to the plants. As a result, the excess dose of nitrogen fertilizer in Munshiganj may act as a catalyst to increase the probability of late blight. The findings also showed that 73.6% of farmers observed unexpected flowering in certain potato cultivars, which corresponded to the higher application of phosphate and potassium fertilizers aimed at late blight control. Furthermore, this study reported infestations of Solanaceous weeds, specifically Solanum torvum and Physalis heterophylla, in potato fields. Finally, our findings demonstrated that more than 68.7% of the potato growers intend to adopt disease-resistant GE potato as that may reduce the need for excess fertilizer use and thus reduce cultivation costs.

Enhancing the Agronomic Performance of Potassium Fertilizer and Potassium-Bearing Minerals in Sandy Loam Soil by Adding Humic Acids and Mycorrhiza

Enhancing the Agronomic Performance of Potassium Fertilizer and Potassium-Bearing Minerals in Sandy Loam Soil by Adding Humic Acids and Mycorrhiza

Влияние осадков сточных вод на тест-растения и агрохимические свойства почв

Purpose: to assess the fertilizing value of sewage sludge. Materials and methods. The material used for research was sewage sludge from municipal wastewater treatment plants in Novocherkassk with a three-year stay period on the sludge map. The research was carried out as a part of a vegetation experiment on soils selected from agricultural lands in Aksai district Rostov region. According to the analysis, the soils are non-degraded, non-saline with a low humus content and an average nutrient content. The granulometric composition of soils is dominated by coarse silt fractions. Sewage sludge, on the contrary, is characterized by a high content of organic matter and nutrients; sand fractions predominate in the granulometric composition. Radish and watercress were used as test plants as they were the most sensitive to the presence of contaminants. Soil bioproductivity was assessed by seed germination, total biomass, and average biomass per plant. Results and discussions. The best germination of plant seeds was noted in variants with the application of sewage sludge to soils in comparison with both the control and the variant of using fertilizers in similar doses of the active substance. Under the influence of sewage sludge, changes in the qualitative composition of soils were noted: the amount of nitrates, phosphates, calcium ions and sulfates increased, and the content of organic matter increased. Conclusions. The positive effect of sewage sludge on plants has been determined: the radish yield increased by 55 % with the use of sewage sludge, and by only 10 % with the use of azofoska (nitrogen-phosphorus potassium fertilizer); the watercress yield increased by 29 % against the background of the use of sewage sludge and by 2 % against the background of the use of azofoska. In variants with the application of sewage sludge, an increase in the content of organic matter by an average of 30 % is observed. In soil samples with sewage sludge, an increase in the nitrogen content by 30–59 %, phosphorus by 67–78 % compared to the control was noted, and when azofoska was added, in comparison with control samples, the amount of nitrogen increased by 5–23 %, and phosphorus by on average by 50 %.

Growth and Yield of Sunflower under the Integrated Farmyard Manure and Potassium Fertilization

The study was conducted during the autumn of 2022 Session at the Students' Experimental Farm Department of Agronomy, Sindh Agriculture University Tandojam, using a Randomized Complete Block Design. Objective: To assess how varying levels of Farmyard Manure and potassium affect the growth and seed production of sunflowers. Methods: The study utilized five different Farmyard Manure treatments and three potassium stages. The variety HO-1 underwent the following treatments: T1 = Control (0-ton Farmyard Manure+ 0 kg ha-1 potash), T2 = 5-ton Farmyard Manure+ 30 kg ha-1 potash, T3 = 5-ton Farmyard Manure+ 60 kg ha-1 potash, T4 = 5-ton Farmyard Manure+ 80 kg ha-1 potash, T5 = 5-ton Farmyard Manure+ 120 kg ha-1 potash. Results: The best results were found in T5 (5 tons of Farmyard Manure + 120 kg ha-1 Potash), which had the largest plant girth (11.2 cm), largest head diameter (48.5 cm), tallest plant (247.4 cm), highest number of seeds per head (1971.3), heaviest seed weight (69.5 g) per head, seed index (34 g), and maximum seed yield (2725.7 kg ha-1). T4 closely trailed, showing positive results (5 tons of farmyard manure plus 80 kg ha-1 potash). Conclusions: In conclusion, the study demonstrates that the optimal combination for maximizing sunflower growth and yield is the application of 80 kg ha-1 of potassium and 5 tons of Farmyard Manure.

The DRIS methodology to determine the best balance of Nitrogen, phosphorus and potassium levels on the yield of Chickpea plant (Cicer arietinum L.)

This experiment was conducted during the spring growing season of 2020 conducted in the field at the Grdarasha farm field of Agricultural Engineering College, Salahaddin University in Erbil, located in the south of Erbil city, Latitude: 36.11284 N, Longitude: 44.01247 E. The soil texture class was silty clay loam, the type of soil vertisols, to study the effect of four levels of phosphorus TSP (0, 20, 40, 60) Kg P. ha-1,Three levels of K (0, 15, 30) Kg K. ha-1, and Three levels of N (0, 15, 30) Kg N. ha-1. There combination of yield components and nutrient balance of chickpea plants by using DRIS methodology, by using; split split block design with three factors (N, P, and K) 36 treatment with 3 replicates was used. The main results could be summarized as The combination between Nain plot potassium, Sub main plot nitrogen, and Sub sub main plot phosphorus levels affected the yield of the chickpea plant significant also the maximum yield was recorded in treatment combination (K2N1P2) was (1.55Mg ha-1). Whereas the lowest mean value (0.73Mg ha-1) was recorded from the treatment combination (K0N0P0). The combined effect of nitrogen, phosphorus and potassium fertilizer on nutrient balance indices (NBI) and yield in chickpea plants. The lowest nutrient balance index was recorded from the treatment combination (K2N1P2).

Yield Response of Cowpea (Vigna unguiculata L.) to Poultry Waste Application With Different Rates of Potassium and Phosphorus Inorganic Fertilizers

Poultry waste is a rich source of nitrogen nutrient compared to other elements. In crop cultivation, combined application of organic manures and inorganic fertilizers increase soil nutrients which are available to plants. Cowpea (Vigna unguiculata L. walp) is a significant grain legume production and it is used as a source of low cost protein for human consumption particularly in the developing countries. Thus, the experiment was conducted to determine the effects of poultry waste with phosphorus and potassium inorganic fertilizers on seed yield of cowpea (Vigna unguiculata L.). The pot experiment was designed in a Completely Randomized Design (CRD) with six treatments and seven replicates. Treatments included T1 – 100% inorganic fertilizer [35 kg ha-1 urea, 100 kg ha-1 triple superphosphate (100% TSP) and 75 kg ha-1 muriate of potash (100% MOP)], T2 – 10 t ha-1 poultry waste alone, T3 – 10 t ha-1 poultry waste + 25% TSP + 25% MOP, T4 – 10 t ha-1 poultry waste + 50% TSP + 50% MOP, T5 – 10 t ha-1 poultry waste + 75% TSP + 75% MOP, T6 – 10 t ha-1 poultry waste + 100% TSP + 100% MOP. The result confirmed that the poultry waste with potassium and phosphorus inorganic fertilizers had significant differences (P<0.05) on most of the agronomic parameters tested in this experiment. Results revealed that application of 10 t ha-1 poultry waste with 100% TSP and 100% MOP treatment (T6) showed the best treatment for cowpea yield in term of seed yield. But significant variation on seed yield was not observed between T5 (10 t ha-1 poultry waste with 75% TSP and 75% MOP treatment) and T6 (10 t ha-1 poultry waste + 100% TSP + 100% MOP) treatments. Therefore, application of 10 t ha-1 poultry waste reduces the usage of inorganic fertilizers (urea by 100%, TSP by 25% and MOP by 25%) for obtaining better seed yield in cowpea cultivation.