NPK Fertilizer Research Articles

Long‐term fertilization regulates dissimilatory nitrate reduction processes by altering paddy soil organic carbon components

AbstractTo enhance rice yields, synthetic nitrogen (N) fertilizers are often applied in rice paddy fields. Under waterlogged conditions, denitrification, anaerobic ammonium oxidation (anammox) and dissimilatory nitrate reduction to ammonium (DNRA) are the main N transformation processes. However, the effects of long‐term fertilization on the dissimilatory nitrate reduction processes remain largely unclear. Here, we investigated rates of denitrification, anammox and DNRA and the abundance of bacterial and nitrate reduction‐related genes (16S rRNA, narG, nirK, nirS, nosZ and hzsB) in rice paddy fields under different fertilization regimes [i.e., non‐fertilization (CK), NPK fertilization (NPK) and NPK fertilization plus straw returning (NPKS)]. The rates of denitrification, anammox and DNRA in the CK treatment were 46.18, 0.35 and 1.29 nmoL N g−1 h−1, respectively, which were significantly (p < .05) increased by 7.32%–27.78%, 2.45–4.12 folds and 1.01–13.23 folds by NPK and NPKS treatments. This was largely consistent with the increased bacterial and nitrate reduction‐related gene abundances in the NPK and NPKS treatments. In addition, NPKS also significantly increased the relative contribution of DNRA to the total nitrate reduction relative to NPK and CK treatments, indicating that NPKS was more beneficial to N retention in the paddy field. Changes in rates of dissimilatory nitrate reduction processes in response to NPK and NPKS treatments were correlated to variations of soil total N, ammonium contents, pH, soil organic carbon (SOC) contents and nitrate reduction‐related genes, among which SOC contents had the highest explanation. Specifically, fulvic‐like compounds, alkyl C and methoxyl and nitrogen‐alkyl C were the key components determining denitrification, anammox and DNRA rates, respectively. Overall, our study suggests that long‐term NPK and NPKS fertilization stimulate rates of dissimilatory nitrate reduction processes mainly by altering soil C components and NPKS is more effective in maintaining soil fertility in the paddy field.

Effects of surface hardening on hardness and tensile strength of locally manufactured feed mill hammers

Animal feed is a major production cost of raising livestock and accounts for about 65 - 68 % of the total production cost, mainly ingredients and processing costs. During feed manufacturing, a hammermill is required for the grinding process to produce quality feed. However, the absence of durable hammers on the local market in Ghana and the high cost of imported hammers compels feed producers to resort to locally manufactured hammers which wear fast due to poor quality of the material. This study considers the application of two surface hardening techniques: (i) carburizing (charcoal and Barium Carbonate (BaCO3) as activator) and (ii) carbonitriding (charcoal, NPK fertilizer as a nitrogen source and Barium Chloride (BaCl2) as activator) in combination with three different quenching media (water, air and oil), to improve the material properties of locally produced hammermill hammers. The surface hardening experiments were performed at 900 oC for 3 h after which the samples were quenched. Tempering was performed afterwards at 160 oC for 1 h. Carbonitriding and water quenching treatment had the best effect on hardness and tensile strength of all the treatments. It yielded the highest surface hardness and tensile strength of 410.06 HV and 768.79 MPa, respectively, representing about a 218 % increase in hardness and a 47 % increase in tensile strength compared to the control sample, which were 128.92 HV and 522.41 MPa, respectively. The result implies hammers produced with this carbonitriding surface hardening and water quenched technique would have improved hardness and wear resistance compared to untreated hammers.

INFLUENCE OF DIFFERENT NUTRIENT SOURCES AND GENOTYPES ON THE CHEMICAL QUALITY AND YIELD OF LETTUCE

<p>The aim of this study was to examine the effect of different fertilizers on the yield and antioxidant capacity of two lettuce genotypes “Santoro RZ” and “Kiribati RZ”.</p> <p>Lettuce genotypes are fertilized with organic fertilizer (Slavol) and organic-inorganic NPK fertilizer (Fitofert hemisuper plus ) during the vegetation. The analyzed parameters were root length and head weight of lettuce, total phenols, and flavonoids, as well as antioxidant capacity. Lettuce genotypes “Santoro RZ” and “Kiribati RZ” fertilized with organic fertilization showed the highest content of total phenols (358.13 ± 1.30 mg RU/100 g of fresh sample), the total content of flavonoids (114.22 ± 0.3 mg RE/100 g of fresh sample) and antioxidant capacity (neutralization of DPHH radicals 58.72 ± 1.88%).</p> <p>The results revealed that the yield and antioxidant capacity of lettuce can be improved by using organic fertilizers.</p>

Recycling potassium from cow manure compost can replace potassium fertilizers in paddy rice production systems

The prevalence of K deficiency and negative K balance in rice production increases the demand for K fertilizer. However, the primary source of K fertilizer, potash rock, is limited. Recycling K from cow manure compost (CMC) is a sustainable solution. Nevertheless, the effects of substituting K fertilizer with CMC on rice yield, soil K fertility, and partial K balance (PKB) are not well understood. Therefore, a field experiment with four treatments (control - unfertilized, MNP K - CMC plus NPK fertilizer, MNP ½ K - CMC plus NP and 50 % K fertilizer, and MNP - CMC plus NP fertilizer) was conducted from 2020 to 2022 to study the effects of replacing K fertilizer with K from CMC on rice growth, yield, plant K uptake, soil K fertility, and PKB. The results indicated that K input from CMC exceeded the recommended K fertilizer level, sufficient for optimal rice growth and yield over three growing seasons and plant K uptake in the last two seasons. Plant K uptake increased with total K input and reached a plateau when total K input approached the maximum plant K uptake. In the MNP treatment, PKB was negative in the first two seasons but became positive in the last season, owing to the equivalence between K input from CMC and plant K uptake. Key factors influencing PKB in this treatment were K input from CMC and plant K uptake. Increasing the CMC application rate during the first two seasons could lead to a positive PKB. In this treatment, soil exchangeable K changed correspondingly with PKB, decreasing in the first two seasons but increasing in the last season. Overall, determining the appropriate amount of CMC application for a positive PKB is vital for the sustainability of substituting K fertilizer with K from CMC in paddy rice systems.

Effect of Providing Pearl NPK Fertilizer on the Growth and Production of Sweet Corn (Zea mays saccharata Sturt)

This research was conducted in the experimental garden of the Faculty of Agriculture, Klabat University, from August to December 2018. The research aimed to determine the response to the growth and production of sweet corn due to the application of NPK Mutiara fertilizer and to obtain the correct dose of NPK Mutiara fertilizer for the growth and production of sweet corn. This research used a Randomized Block Design (RAK) with four levels of treatment, namely T0 (without Mutiara NPK fertilizer treatment) as a control, T1 (2 gr/plant), T2 (4 gr/plant), and T3 (6 gr/plant) where each treatment was repeated four times. The research results were that the dose of Mutiara NPK fertilizer did not influence plant height and number of leaves because the growth response of sweet corn was not large enough to have a real influence on plant height and number of sweet corn leaves. The Mutiara NPK dosage influences the flowering age and cob weight because the response of the sweet corn plants is large. The dose of Mutiara NPK fertilizer does not affect plant height and number of leaves but does affect flowering time and ear weight. The best dose of Mutiara NPK fertilizer is 6 gr/plant.

Improving microbial properties in Psamments with mycorrhizal fungi, amendments, and fertilizer

Psamments is sandy soil with a texture class of fine loamy sand or coarser in all layers, deposited sands such as dunes in beach lands with low soil biological fertility. Adding mycorrhizal, soil amendments, and inorganic fertilizers could improve soil fertility. This research aimed to investigate the effect of mycorrhizal, soil amendments, and inorganic fertilizers on soil organic carbon (SOC), microbial biomass carbon (MBC), glomalin-related soil protein (GRSP), and root infections in Psamments. This research was a pot experimental in screenhouse, arranged in a factorial completely randomized design with three factors: three of mycorrhizal doses, M0 = 0 spore pot-1, M1 = 3 spores pot-1 and M2 = 6 spores pot-1; three types of soil amendments, P0 = non amendment, P1 = cow dung 60 t ha-1, P2 = rice husk biochar (RHB) 25 t ha-1; and two doses of inorganic fertilizer, A0 = 0 kg ha-1, A1 = 100 kg ha-1 NPK (15:15:15) fertilizer, replied three times. The results showed that mycorrhizal combination with RHB and inorganic fertilizer increased MBC up to 23 times than control. The combination of mycorrhizal-cow dung-inorganic fertilizer was the highest of total-GRSP (4.4 times) and mycorrhizal dose 6 spores pot-1 with both amendments and inorganic fertilizer increase root infection up to 90%. It was proven that mycorrhizal with soil amendments and inorganic fertilizers could improve the microbial properties of Psamments.

Compost of peanuts residue and rice straw compost on soil Nitrogen forms and upland rice yield

<p>This study provides an innovation in making compost from rice straw (low quality) mixed with peanut residue (high quality) to improve the quality of rice straw compost. The purpose of this research was to discover the optimum composition of a mixture of peanut residue and straw for mineralization, absorption, and Nitrogen Use Efficiency (NUE) and its effect on upland rice plants. The study was conducted in three stages. The first stage determined the quality of five compost mixtures: C1, C2, C3, C4, and C5. The second phase of testing for cumulative N minerals was performed after 1, 2, 4, and 8 weeks of incubation. The third stage examined the impact of the compost mixture on the growth and yield of upland rice in comparison with two treatments, namely the control and NPK fertilizer. The results showed a similarity in the forms of mineralization, where the cumulative N mineral increased with the addition of peanut residue to the compost mixture. The use of a mixture of peanut residue and rice straw compost increased net mineralization by 37.27% (C5) to 59.48% (C1), N uptake by 49.19% (C5) to 62.95% (C3), and NUE by 15.04% (C4) to 51.48% (C3). A strong relationship was detected between the quality of the compost and the forms of N in the soil, particularly the nitrate content, total N minerals, and N microbial biomass, with correlation coefficients of 0.92, 0.88, and 0.94, respectively. A strong to very strong relationship was detected between N form and N uptake (r = 0.84), plant height (r = 0.79), number of tillers (r = 0.78), yield of rice plants (r = 0.93 (plant total dry weight), and r = 0.76 (grain weight). The optimum N uptake, NUE, and yield of upland rice were shown by C3 treatment of 405.28 mg pot<sup>-1</sup>, 42.21%, and 6.19 tons ha<sup>-1</sup>, respectively.</p>

Improving the Quality of Functional Food Crops and Land Efficiency by Intercropping System on Application of Integrated Fertilizer

The intercropping system and integrated fertilizers were applied in the research to improve land efficiency and the quality of sweet corn and vegetable soybean crops. The study was conducted in the Giwangan Village of Umbulharjo Yogyakarta, Indonesia, and was set up using a three-replication factorial Randomized Complete Block Design. Three organic fertilizer sources (cow manure, chicken manure, and composted waste) made up the first factor, and the second factor was NPK fertilizer doses (200, 300, and 400 kg ha-1). Two control treatments were also made, which resulted in 33 experimental plots. The observed data were subjected to analysis of variance and Duncan’s Multiple Range Test at a significance of 5%. The study’s findings demonstrated that the combination of 300–400 kg ha–1 NPK fertilizer and chicken manure increased variables such as the content of vitamin C and pro-vitamin A, number of seed rows, number of 2-3 seed pods, and sweetness level of soybean and sweet corn, as well as the land equivalent ratio, land equivalent coefficient, competition index, system productivity index, and relative yield mixture.

The Effect of Doses of Cow Manure and NPK Fertilizer on the Growth and Yield of Purple Eggplant (Solanum Melongena L) Cultivars Mustang F1

The aim of this study was to determine the effect of doses of cow manure and NPK fertilizer on the growth and yield of purple eggplant plants (Solanum melongena L) Mustang cultivar F1, as well as to determine the relationship between the components of growth with components of purple eggplant plants (Solanum melongena L). The study was conducted in the village of Cigintung, Kuningan District, Kuningan Regency from September 07, 2019 to November 24, 2019. The location was at an altitude of 400 m above sea level (asl) with clay type, rainfall type C (Slightly wet). The method used was an experimental method with a factorial Randomized block Design (RBD), the treatment consisted of two factors that were repated three times. The first factor is cow manure consisting of three levels (K 1 = 10 tons/ha, K 2 = 15 tons/ha, K3 = 20 tons/ha). The second factor is NPK fertilizer consisting of three levels (N 1 = 100 kg/ha, N 2 = 200 kg/ha, N 3 = 300 kg/ha). The results showed that the different treatment dosages of doses of cow nanure and NPK fertilizer do not have a real effect on all ages observations on plant height, number of fruit plants, fruit length, fruit diameter, fruit weight per plant, fruit weight per plot.

Response of micropropagated tissue culture banana (Musa spp.) to acclimatization using arbuscular mycorrhiza fungi

The production of banana seedlings through tissue culture provides a reliable source of numerous, disease free, quality plantlets. However, the micropropagation process is faced with a number of challenges. In this study we are focusing on the improvement of survival and growth of the resultant plantlets during the acclimatization process. The viability of arbuscular mycorrhiza fungi (AMF) symbiont in the acclimatization process was assessed. Tissue culture bananas (Kienyeji, Kiganda and Ng’ombe local cultivars) were inoculated with single species AMF Rhizophagus irregularis and Funneliformis mosseae as well as commercial AMF Rhizatech. The survival rate was assessed and plant growth evaluated at a two week interval. Destructive harvesting was conducted followed by assessment of root, shoot and total biomass. The results demonstrated that Kiganda treated with Rhisophagus irregularis and Funneliformis mossae recorded better survival rates compared to treatments with NPK fertilizer and commercial AMF (Rhizatech). Kienyeji cultivar however had a better survival rate when treated with commercial AMF (Rhizatech). Ng’ombe cultivar was very resilient having 100 % survival rate when treated with indigenous AMF, commercial AMF (Rhizatech) and NPK. There were significant differences in the shoot dry weight, root dry weight and biomass in the three banana cultivars. Kiganda and Kienyeji cultivars had the highest biomass when treated with Funneliformis mossae of 0.52 g and 0.83 g respectively. The results in this study confirm that the use of AMF in the acclimatization process improves the overall seedling output of the micropropagation process during the nursery stage of production.

Soil Chemical Properties and Microbial Behavior under Short-Term Organic and Mineral Fertilization within Different Crops

Agronomic practices can have a negative impact on soil health and quality and ecosystem resilience. The objectives of the study were (1) to evaluate the soil chemical properties and microbial abundance under short-term application of organic and mineral fertilizers and different cultivated crops and (2) to observe the antifungal efficacy of microorganisms isolated from the studied soil. A field trial was conducted in the 2021–2022 period on a preluvosoil-type soil in four randomized blocks with eight fertilizer treatments based on manure compost (MC) and MC + mineral fertilizer (V1—control-soil; V2—NPK only; V3—15 t/ha MC; V4—15 t/ha MC + NPK; V5—30 t/ha MC; V6—30 t/ha MC + NPK; V7—60 t/ha MC; and V8—60 t/ha MC +NPK) and four crops (winter wheat—Triticum aestivum L., maize—Zea mays L., soybean—Glycine max L., and a mixture of perennial grasses and legumes). In almost all treatments, the soil pH decreased during the summer–autumn period. The organic carbon (Corg) and humus contents increased compared to the initial state of the soil after the application of different doses of MC and MC + NPK fertilization in almost all treatments. The microbial load of the soil was influenced by the fertilization regime and crop species, but there were no significant differences between the variants. The highest bacterial load was recorded in soil cultivated with a mixture of perennial grasses and grain legumes, i.e., in the variant with 15 t/ha MC, followed by soil cultivated with maize and fertilized with 30 t/ha and 60 t/ha MC. A higher number of fungi was observed in the mixture of perennial grasses and legumes, and Rhizobium population was higher, especially in the winter wheat plots, despite the fertilization regime. The antifungal efficacy of the microorganisms isolated from the samples was medium to low, except in the winter wheat experiment, where the efficacy against Fusarium culmorum was medium to high and against other pathogens was medium. In the other crops within the experiment, the antagonistic activity of the soil microorganisms was medium to low.

Long-term organic fertilization reshapes the communities of bacteria and fungi and enhances the activities of C- and P-cycling enzymes in calcareous alluvial soil

Soil microbial communities and extracellular enzymes are pivotal in governing the dynamics of soil carbon (C) and phosphorus (P) cycling. Nevertheless, comprehending the underlying regulatory factors and intricate interactions among these vital indicators remains an inadequately explored aspect, especially within the scenario of long-term fertilization. Long-term fertilization experiments were conducted on calcareous alluvial soil. The five fertilization regimes selected were as follows: without fertilization treatment (CK); inorganic NK fertilization treatment (NK); inorganic NPK fertilization treatment (NPK); organic fertilization treatment (M); and combined inorganic NPK with organic fertilization treatment (NPKM). The soil physicochemical properties, β-glucosidase (BG), and alkaline phosphomonoesterase (ALP) activities were determined, together with microbial (bacterial and fungal) community DNA sequences and subsequent bioinformatics analysis after 38 years of different fertilization. The results showed that the content of soil organic carbon (SOC) and available P and the activities of BG and ALP were the highest after M and NPKM treatments, which were 79–104 %, 26–36 times, 161–171 %, and 75–91 % higher than CK, respectively. Hierarchical clustering analysis showed that the bacterial and fungal community structures in M and NPKM treatments were similar, but the community structures in non-organic fertilization treatments (CK, NK, and NPK) were significantly different from those in organic fertilization treatments. The indicator species and correlation analysis combined revealed that most indicator species in organic fertilizer treatments were significantly positively correlated with soil BG and ALP, while most indicator species in non-organic fertilizer (CK and NK) treatments were significantly negatively correlated with soil BG and ALP. Organic fertilization treatments favored the growth of the bacterial genus Lysobacter and the fungal genera Acremonium and Mortierella and were significantly positively correlated with BG and ALP activities. Redundancy analysis revealed that SOC is the most important factor in shaping microbial community structure. Co-occurrence network analysis showed organic fertilization had higher network complexity, more keystone taxa, and more associations among microbial taxa compared with non-organic fertilization (CK + NK). Structural equation models revealed that microbial community structure is the direct driving factor of BG and ALP activities and their interactions, and SOC modulated the relationship between microbial community structure and BG and ALP activities. This study highlights how the application of organic fertilizer enhanced the C- and P-cycling enzyme activities, reshaped the soil microbial communities, and regulated these crucial indicators and their interactions by SOC.

Response Land (Ipomoea reptans Poir) as a Result of Fertilizing NPK and Manure of Various Doses Under the Shade of Citrus Plants

Organic fertilizers can improve soil fertility, but the availability of nutrients is generally low due to low nutrient content. So that the response of plants to organic fertilizers will be slower, because organic fertilizers are slow release. Therefore, it is necessary to add fast-release inorganic fertilizers such as Pearl NPK fertilizer to increase plant growth. This study aims to determine: (1) Get the right dose of NPK Mutiara 16-16-16 in increasing the growth and yield of land water spinach, (2) Get the right dose of cow manure to increase the growth and yield of land water spinach, (3) Obtain the interaction between the dose of NPK Mutiara 16-16-16 and the right cow manure in increasing the growth and yield of ground land water spinach plants. The results showed that: The application of NPK Mutiara at various doses showed that the increasing dose of NPK Mutiara fertilizer increased yields, this was clearly seen in the plant height and plant yield per plot with the application of NPK Mutiara at a dose of 300 kg/ha (m3). However, the dose of 20 tons/ha (p2) gave higher yields compared to the dose of 10 tons/ha (p1) in the variables fresh plant weight, fresh canopy weight, yield per plot, and marketable yield. There was no interaction between giving NPK Mutiara 16-16-16 and cow manure fertilizer.

Influence of Integrated Nutrient Management on Physico-Chemical Properties of Soil, Growth, Flowering and Yield of Guava Grown as a Component Crop in Coconut-Based Cropping System

An experiment on integrated nutrient management in guava grown as a component crop in a coconut-based cropping system was conducted under the coastal condition of Odisha. Adoption of integrated nutrient management like the application of organic manures with or without NPK fertilizers resulted in improvement in the physico-chemical properties of soil, which was reflected in terms of pH, organic carbon content, available nitrogen, phosphorus and potash content. Among the different combination of integrated nutrient management applied in guava, the plant height, canopy spread, flushing intensity, yield and yield attributing parameters. The maximum available soil nitrogen, available phosphorus and available potassium contents were estimated to be maximum in the treatment applied with 50% RDF +50% N through vermicompost + FYM +bio fertilizer, while the soil pH was highest owing to application of 75% RDF + 25% N through vermicompost + FYM which was at par with results obtained with application of 75% RDF + 25% N through vermicompost and 75% RDF +25% N through vermicompost + FYM +bio fertilizer.

Bio-desalination of sea water using floating plants; A laboratory experiment on three mangroves species

The plant species mangrove has been knowed to be effective for the bio-desalination process. However, there is currently no scientific evidence supporting the ability of mangrove bio-desalination when implemented through the floating method. This laboratory-scale study aimed to evaluate the bio-desalination of several mangrove species using the floating method. This study consisted of four treatments and three replicates. Treatments included a control group without mangroves (treatment A) and three treatments using mangroves (treatments B, C, and D), Bruguiera sp., Rhizophora sp., and Avicennia sp., which were positioned floating in a tank using a tray. During the eight weeks of rearing, nutrients were provided through 60 mL liquid NPK fertilization. The results showed that there was a decrease in salinity concentration in all mangrove treatments between 22.5-23.9 ppt from the initial salinity of 30 ppt. Different results were observed for the treatment without mangroves, and the salinity concentration tended to increase until the end of the research to 31.6 ppt. The highest Salinity Reduction Efficiency (SRE) was achieved by Avicennia sp.. (25.1%), followed by Rhizophora sp. (22.8%), and the lowest in Bruguiera sp. (20.3%). The results of this study showed that bio-desalination using mangroves had a significant effect on SRE, and each treatment indicated a significant difference (p<0.05). The results of this study provide initial evidence of the potential of the mangrove floating method for bio-desalination of seawater into brackish water.

Impact of Long-term Use of Fertilizers and Manure on Distribution of Soil-inorganic Phosphorus Fractions in a Vertisol

The field experiment was conducted during the kharif season under the AICRP on Long-Term Fertilizer Experiment at the Research Farm, Department of Soil Science and Agricultural Chemistry, JNKVV, Jabalpur (M.P.), India. The investigation was carried out to assess the distribution of P fractions in Vertisol after the harvesting of the soybean crop. Eight treatments were imposed with four replications in a simple randomized block design. The treatments were applied in combination with different doses of fertilizer viz., T1 (50% NPK), T2 (100% NPK), T3 (150% NPK), T4 (100% N), T5 (100% NP), T6 (100% NPK+FYM), T7 (100% NPK-S), and T8 (control). Through the findings, the soil pH and electrical conductivity (dS m-1) did not show significant changes even after the long-term application of various fertilizer levels compared to their initial values. The treatment with 100% NPK + FYM exhibited the highest organic carbon (g kg-1) content and available N, P, and K (kg ha-1) content over the control. The various forms of phosphorus in the soil were observed in the following order: Ca-P > Fe-P > Al-P > Occluded-P > Saloid-P . The Ca-P content was highest when 100% NPK fertilizer and farmyard manure (FYM) were used together. The analysis showed that the presence of saloid-P significantly influences the availability of phosphorus in Vertisol soil. Based on the current investigation, it is recommended to use integrated nutrient management, which includes both 100% NPK fertilizer and FYM, to prevent phosphorus deficiency in soybean cultivation in Vertisol.

Yield Performance of Chia (Salvia Hispanica L.) In Response to Planting Spacing and Npk Fertilizers

Optimization of plant spacing, and fertilizer dose is very important for realizing maximum yield of a crop. An experiment was conducted at the Agronomy Field Laboratory of Bangladesh Agricultural University, Mymensingh during November 2020 to March 2021 to determine the effect of different spacing and NPK fertilizer levels on yield and yield attributes of chia seed. The experiment consisted of four different spacing viz. 30 cm × 15 cm (S1), 30 cm × 30 cm (S2), 40 cm × 15 cm (S3) and 40 cm × 30 cm (S4) and five levels of NPK fertilizer viz. No NPK (F0), 30: 20: 25 kg NPK ha-1 (F1), 60: 40: 50 kg NPK ha-1 (F2), 90: 60: 75 kg NPK ha-1 (F3) and 120: 80: 100 kg NPK ha-1 (F4). The experiment was laid out in a factorial randomized complete block design (RCBD) with three replications. The results revealed that 40 cm × 30 cm spacing produced the highest number of inflorescences plant-1, seed yield and haulm yield. The fertilizer level 90: 60: 75 kg NPK ha-1 showed the highest seed yield and haulm yield while 120:80 :100 kg NPK ha-1 exhibited the maximum number of inflorescences plant-1. The combination of 30 cm ×30 cm spacing and 90: 60: 75 kg NPK ha-1 produced the highest number of inflorescences plant-1 and seed yield whereas the combination of 40 cm × 30 cm spacing and 90: 60: 75 kg NPK ha-1 had the highest haulm yield. The present study concluded that cultivation of chia at a spacing of 30 cm × 30 cm and fertilized with 90: 60: 75 kg NPK ha-1 could be considered as the promising practice for reasonable seed yield.
 Bangladesh Agron. J. 2023, 26(1): 122-127

RESPONSE OF COTTON CULTIVARS TO SOIL AND FOLIAR APPLIED FERTILIZER IN KABBA, KOGI STATE, NIGERIA

The experiment was carried out at Kabba College of Agriculture experimental field in 2020 and 2021 cropping seasons to evaluate response of cotton cultivars to soil and foliar applied fertilizer. The experiment was performed in a randomized complete block design with two factors arranged in split plot arrangement in three replications. The first experimental factor was a cultivar, include two cotton varieties Hybrid and Lokoja local (abbreviated as C1 and C2) were used. The second experimental factor was the different nitrogen sources applied at five levels, NS1 = No Nitrogen source (control), NS2 = NPK (20:10:10 plus boron) fertilizer applied into soil alone = 80kg NPK & B, NS3 = NPK & B at 50% (40kg N) + Agric Zyme 50% (40 kg N), NS4 = NPK & B at 75% (60kg N) + Agric Zyme at 25% (20kg N) and NS5 = NPK & B at 25% (20kg N) + Agric Zyme at (60kg N). Data were collected on growth characters such as plant height, stem girth, number of leaves and leaf area fresh and dry weight of cotton. Yield characters observed were number of flowers per plant, cotton ball per plant, cotton yield per plant and cotton lint yield. All plots with NPK&B and Agric Zyme produce better growth and yield characters than the control. All plots with NPK&B alone or in combination with Agric Zyme at reduced level produced similar growth characters. Cotton with fertilizer application either singly or combined produced higher number of flowers and cotton balls compared to the control. Cotton grows through hybrid seeds gave more flowers and cotton balls more than Lokoja local seeds used. Cotton with fertilizer application were susceptible to pest attacked compared to cotton grow in the control plots. Cotton grows with the use of hybrid seed gave higher number of aborted flowers than the Lokoja local seed used. Though, cotton plant grows with NPK&B at 80 kg /ha gave the highest yield of cotton. All other plots with combined application of NPK&B and Agric Zyme produced yield comparable to plots with NPK&B at 80 kg /ha. Among cotton with combined application of NPK&B and Agric Zyme, plots treated with NPK & B at 25% (20kg N) + Agric Zyme at 75% (60kg N) gave the greatest yield. Cotton with hybrid seed produced cotton yield higher than the Lokoja local seed. The increment in hybrid cotton yield over Lokoja local seed is 58.52%. Cotton farmers in the study area should grow hybrid cotton using any of the treatment combinations especially NPK & B at 25% (20kg N) + Agric Zyme at 75% (60kg N).

Evaluation of nano-nitrogen fertilizers and other nitrogen sources on the performance of Guinea grass plants grown in newly reclaimed soil under water deficiency

Water deficiency and chemical fertilizers' pollution are two of many factors causing imbalance in the ecosystem rhythm, which reflects on farm livestock quality and quantity, particularly in arid and semi-arid regions. Limited research is available on the use of different sources of nitrogen fertilizers on pasture crops; hence, an open field research experiment was carried out in newly reclaimed soil to investigate the effect of different sources of nitrogen fertilizers on maximizing protein level and production of Guinea grass (Panicum maximum Jacq.) plant under water deficiency. Present data from two successive seasons revealed that: plants received nitrogen in the form of nano particles recorded significant increases in yield, morphological parameters, leaf anatomy, and chemical composition (macro and micro nutrients, total carbohydrates, plant pigments and crude protein) over control (plants that received the recommended dose of NPK fertilizers) in both growing seasons. In addition, endogenous hormones; gibberellins (GA3) and abscisic acid (ABA) beside enzymes; superoxide dismutase (SOD) and peroxidase (POD) had been affected by different treatments. The lowest amounts of cellulose, hemicellulose and lignin were resulted from nitrogen nano particles treatment, while the rates of leaf photosynthesis, stomatal conductance, intercellular CO2 concentration, and water use efficiency were enhanced also by nitrogen nano particles treatment application. The present findings suggested that increasing crude protein level of Guinea grass plant grown in newly reclaimed soil by addition of the mentioned nanoparticles could be a promising approach to improve crop productivity under water deficiency and reduce environmental pollution.

Litter from Native Shrubs in the Senegal River Valley Induces Modifications in Nematode Communities and Enzyme Activities in Cultivated Sandy Soils

ABSTRACT To reduce plant-parasitic nematodes (PPNs), an alternative solution based on amendments from selected native shrub was used to favor mainly the increase of free-living nematodes (FLNs) that include high trophic (bacterivorous, fungivorous, omnivorous, and carnivorous) nematodes and influence soil microbial activities. The consequences of the subsequent reduce of PPNs of the soil were also determined. Experiments were performed in a shade house using six treatments consisting of shrub residues from Piliostigma reticulatum (Pil), Boscia senegalensis (Bos), and Crotalaria juncea (Cro); a Straw-based Compost (Cs); a Farmer practice (FP) using Nitrogen-Phosphorus-Potassium (NPK) fertilizer; and a control (C0, no amendments). Abundances of nematodes, trophic groups, and nematodes ecological indices were determined. Enzymatic activities (ß-glucosidase and acid phosphatase) and the fluorescein diacetate hydrolysis (FDA) were also determined. Soil amended by Bos and Cro increased the density of nematodes compared to control soil or amended with NPK fertilizer. Indices of taxonomic diversity (H') did not differ significantly between the treatments. However, soils amended with Bos and Cro had the highest enrichment index (EI), and the lowest Nematode Channel Ratio (NCR), indicating that these two shrub residues exhibited a higher food web in response to the available resources provided by the fungal decomposition pathway. Moreover, Bos favored omnivorous and increased enzymatic activities. Bos induce ‘bottom-up’ while Cro induce ‘top-down’ controls on nematode populations.