Fertilizer Nutrients Research Articles

Nutrient Status of Nitrogen, Phosphorus, Potassium and Soil Fertility Levels in Three Different Land Uses in Dolo District, Sigi Regency

This research was conducted to determine nutrient status and soil fertility levels in Dolo District, Sigi Regency, map the soil nutrient status and soil fertility levels in Dolo District, Sigi Regency and as a reference for recommendations for land management in accordance with nutrient status and fertility levels in the three uses. different lands in Dolo District, Sigi Regency. This research was conducted in Langaleso Village and Kabobona Village, Dolo District, Sigi Regency, taking soil samples on cocoa land, deep coconut land and dry land in Dolo District, Sigi Regency. This type of research is a survey method and the data is presented descriptively. By trying to conduct observational surveys and soil sampling by purposive sampling. Soil samples were taken from 3 types of land use, namely cocoa land (K), Kelapa Dalam land (P) and dry land (T). Soil samples were taken at a depth of 0 - 20 cm and 21 - 40 cm. Where each land use is taken at two different locations, each two points of soil sampling and composited so that a total of 12 soil samples are obtained. The results of the research showed that the nutrient status that became an obstacle in soil fertility in Dolo District, Sigi Regency was Soil Reaction (pH) slightly acidic, Cation Exchange Capacity (CEC), C-organic, Nitrogen (N), Phosphorus (P), Potassium ( K) is classified as moderate, and base saturation (KB) is low so that the level of soil fertility on coconut, cocoa and dry fields in Dolo District, Sigi Regency is moderate and has unhealthy/less fertile soil quality.

Nodule Parameters, Quality and Nutrient Uptake of Vegetable Cowpea [Vigna unguiculata subsp. unguiculata (L.) Verdcourt] as Influenced by Foliar Application of Macro and Micro-nutrients

Background: Legumes are one of the major sources of dietary proteins for the people of India and is an inevitable component of vegetarians’ diet. Among them cowpea pods and seeds are rich source of protein and accrue delicacy in cuisines. Adequate amounts of fertilizers applied through most effective and economic means can raise productivity and profitability of cowpea cultivation. Hence the present study was formulated with an objective to study the effect of water-soluble macro and micro nutrient fertilizers on nodulation, quality and nutrient uptake of vegetable cowpea. Methods: Field experiment was conducted at Coconut Research Station, Balaramapuram during the period from 12 November 2020 to 31 January 2021. The experiment was laid out in randomized block design with 13 treatments in 3 replications. The treatments comprised of recommended dose of fertilizers (RDF) as control and RDF + foliar application of NPK 19:19:19 (0.5%) or potassium nitrate (0.5%) alone or in combination with ZnSO4 (0.05 %) and solubor (0.025%). Result: Foliar nutrition of micro and macro nutrients had significant effect on nodulation, quality and nutrient uptake. Foliar nutrition of 19:19:19 resulted in the production of higher number of nodules than KNO3. Among the treatments, RDF (20:30: 10 kg NPK ha-1) + foliar application of 19:19:19 (0.5% ) + solubor (0.025% ) at 45 DAS resulted in higher number of nodules and nodule fresh weight per plant, however higher number of effective nodules was recorded in RDF + foliar nutrition of 19:19:19 (0.5%) alone at 45 DAS. The highest uptake of N, P and K by the crop was also recorded in RDF + foliar application of 19:19:19 (0.5%) + solubor (0.025%) at 45 DAS. Zinc uptake was the highest in RDF + foliar application of KNO3 (0.5%) 45 and 60 DAS and B uptake was the highest in RDF + foliar application of KNO3 (0.5%) + solubor (0.025%) at 45 DAS. The highest crude protein content was recorded in RDF + foliar nutrition of 19:19:19 (0.5%) + ZnSO4 (0.05%) and solubor (0.025%) at 45 DAS fb 19:19:19 (0.5%) at 60 DAS. The treatment, RDF + foliar application of 19:19:19 (0.5%) + solubor (0.025%) at 45 DAS resulted in the highest number of pods and green pod yield per plant in bush type vegetable cowpea.

Impact of Different Approaches of Nutrient Recommendations for Aerobic on Soil Fertility of Alfisols of Eastern Dry Zone of Karnataka

A field experiment to study the impact of different approaches of nutrient recommendations for aerobic on soil fertility of Alfisols of Eastern Dry Zone of Karnataka was conducted during Kharif 2020 at Zonal Agricultural Research Station (ZARS), GKVK, Bengaluru. The experiment was laid out in RCBD comprising twelve treatments replicated thrice. The results revealed that significantly higher grain yield (68.85 q ha-1) was recorded in treatment receiving fertilizer nutrients based on Soil Test Crop Response (STCR) inorganic approach for the targeted yield of 65 q ha-1 based on predicted soil test values which was superior compared to Low-Medium-High (LMH) approach and Blanket recommendation The higher post- harvest soil available nutrient status was registered in STCR integrated approach based on predicted soil test values compared to package of practice and LMH approach.

Process optimization of struvite recovered from slaughterhouse wastewater and its fertilizing efficacy in amendment of biofertilizer

The intensive discharge of slaughterhouse waste into water bodies increases Nitrogen (N), Phosphorus (P) in the wastewater and leads to various environmental problems. On the other hand, the increasing treatment effort after the extraction of these valuable nutrients in the commercial fertilizer reduces the dependence on scarce phosphate resources. The viable solution is to recover N, P as struvite (magnesium ammonium phosphate) from nutrient rich waste water as a small scale treatment unit application. The main parameters that have a significant impact on the process, including pH, Mg: P ratio, and precipitation time, were investigated from slaughterhouse wastewater using a central composite design and the experimental data's were statistically analysed. The results indicated that pH and Mg/P ratio level had a significant impact and thus 85% struvite precipitation efficiency was achieved at 9.6 pH and 1.5 dose mol ratio (mol Mg per mol P), in an inexpensive, stirred tank batch reactor with a retention time of 70 min. The fertilization efficiency was tested on the growth of Solanum melongena L with the obtained struvite and the integration of struvite with the Azospirullum rhizobium and Bacillus megaterium. Treatment of struvite, struvite with Azospirillum rhizobium and Bacillus megaterium increased growth parameters by 10%, 20%, and 25%, respectively, over control. The assessment of growth factors showed the most amazing number of fruits, shoots, and root length in a standard ratio of 60:40 of struvite to bio-inoculants compared to sole struvite fertilizer. Findings of this study would be beneficial to determine the feasibility of slaughterhouse waste as a phosphorus source for struvite recovery.

Delayed autumnal leaf senescence following nutrient fertilization results in altered nitrogen resorption.

Increased atmospheric nitrogen (N) deposition could create an imbalance between N and phosphorus (P), which may substantially impact ecosystem functioning. Changes in autumnal phenology (i.e., leaf senescence) and associated leaf nutrient resorption may profoundly impact plant fitness and productivity. However, we know little about how and to what extent nutrient addition affects leaf senescence in tree species, or how changes in senescence may influence resorption. We thus investigated the impacts of N and P addition on leaf senescence and leaf N resorption in 2-year-old larch (Larix principisrupprechtii) seedlings in northern China. Results showed that nutrient addition (i.e., N, P or N+P addition) significantly delayed autumnal leaf senescence, and decreased leaf N resorption efficiency (NRE) and proficiency (NRP), particularly in the N and N+P treatments. Improved leaf N concentrations were correlated with delayed leaf senescence, as indicated by the positive relationship between mature leaf N concentrations and the timing of leaf senescence. Following nutrient addition, larch seedlings shifted toward delayed onset, but more rapid, leaf senescence. Additionally, we observed an initial negative correlation between the timing of leaf senescence and NRE and NRP, followed by a positive correlation, indicating delayed and less efficient remobilization during the early stages of senescence, followed by accelerated resorption in the later stages. However, the latter effect was potentially impaired by the increased risk of early autumn frost damage, thus failed to fully compensate for the negative effects observed during the early stages of senescence. Improved soil P availability increased leaf N resorption and thus weakened the negative impact of delayed leaf senescence on leaf N resorption, so P addition had no significant impact on leaf N resorption. Overall, our findings clarify the relationship between nutrient addition-resorption and the linkage with leaf senescence, and would have important implications for plant nutrient conservation strategy and nutrient cycling.

Rice Blast, A Major Threat to the Rice Production and its Various Management Techniques

Rice (Oryza sativa L.) is the most important staple cereal crop which is consumed by more than 50% of world population. It contributes 23% and 50% of total calories consumed by world and Nepalese population respectively. Among various abiotic factors affecting rice, rice blast is the most disastrous, causing 70-80% yield loss. This disease was originated in China around 7000 years ago. In Nepal, it was first reported in Thimi, Bhaktapur in 1966. It is caused by a filamentous ascomycete fungus Magnaporthe oryzae (Anaemorphic form- Pyricularia oryzae). It infects all the developmental stage of plant and produce symptoms on the leaf, collar, neck, panicle and even in the glumes. It decreases the rice production by an amount, enough to feed 60 million people every year. Cloudy weather, high relative humidity (93-99%), low night temperature (15- 20°C), longer duration of dew is the most favorable condition for the outbreak of disease. The most usual approaches for the management of rice blast diseases are management in nutrient fertilizer and irrigation, application of fungicides and plantation of resistant cultivars. Besides, the use of extracts of C. arabica are reported to have an inhibitory effect on the disease. Seed treatment with Trichoderma viridae @ 5ml/lit of water have also been found effective. The chemical means of controlling blast disease shall be reduced, instead eco-friendly measures like biocontrol agents, resistant varieties, plant extracts can be practiced for disease control. Different forecasting model can be used in order to predict the disease prevalence.

Woven-fiber microfiltration coupled with anaerobic forward osmosis membrane bioreactor treating textile wastewater: Use of fertilizer draw solutes for direct fertigation

A lab-scale Anaerobic Forward Osmosis Membrane Bioreactor (An-FOMBR) system was established for treating synthetic textile wastewater having Chemical Oxygen Demand (COD) of 3000 ± 150 mg/L using Fertilizer Draw Solutes (FDSs). The study was conducted by using Ammonium Sulphate (SOA), Mono-ammonium Phosphate (MAP), and Mono-potassium Phosphate (MKP) each having 1 Molar (M) concentration which can be used for sustainable water reuse in terms of fertigation without regeneration of FDSs. For treatment of textile wastewater, color and COD removal was found to be in the range of 92.3–96.4 and 97.8–99.2%, respectively. Among the three FDS, MAP showed the best performance for 71 days with stable biogas production. Flux recovery using MAP as DS was less than 75.2% as compared to SOA 78.8 and MKP 82.8% after osmotic backwashing. Fertilizer nutrient concentrations (NH4+1-N, K+1, and total phosphorus) in product water were observed low at the initial cycles, requiring minimum dilution for direct fertigation. Furthermore, for reverse solute reduction, low-cost Woven Fiber Microfiltration (WFMF) was coupled with An-FOMBR and the flux of WFMF was optimized at 2 LMH which exhibited the salinity level within the range of 4.5–7.5 mS/cm and assisted the An-FOMBR in exhibiting a continuous long-term operation in comparison with conventional osmotic membrane process and hence can serve as a sustainable solution for treating high strength textile wastewater.

Yield Variability in Oil Palm Plantations in Tropical India Is Influenced by Surface and Sub-Surface Soil Fertility and Leaf Mineral Nutrient Contents

Oil palm (Elaeis guineensis Jacq.), an industrial oilseed crop, is the most prominent oil-producing crop in the world and one of the highest dry matter producers among C3 plants. It removes large amounts of soil nutrients to support its substantial biomass and oil production. Thus, maintaining adequate levels of limiting nutrients at favorable ratios in the soil is crucial to sustain the required palm nutritional status and oil production over extended periods. We evaluated the levels and ratios of the available soil and leaf nutrients in high-yielding (HYOPP) and low-yielding (LYOPP) oil palm plantations from two locations in southern India and assessed their relations to develop effective nutrient management for sustaining fresh fruit bunch (FFB) production. The FFB yield varied from 2.00 to 31.0 t ha−1 (location 1) and 6.84 to 30.9 t ha−1 (location 2), and the FFB yields of the high- and low-yield population at each location differed significantly. Wide ranges of soil properties, available nutrients, and leaf nutrients concentrations were observed at 0–20- and 20–40-cm soil depths at both locations. The soil nutrient ratios at both sampling depths of the HYOPP were significantly different than the LYOPP at location 1. The mean leaf N (2.09%) and K (0.68%) concentrations at location 2 were significantly higher than those in location 1 (1.85% and 0.54, respectively). The mean leaf concentrations at both locations followed the order N (1.85%, 2.09%) > Ca (1.65%, 1.36%) > K (0.54%, 0.68%) > Mg (0.49%, 0.47%) > S (0.16%, 0.18) > P (0.11%, 0.12%) > B (35.8 mg kg−1, 27.5 mg kg−1). We observed positive and significant correlations between the available N and P at 0–20 cm and between the available N and K as well as Ca and S at both soil depths for HYOPPs. In LYOPPs, the available N was significantly correlated with the available P, K, Ca, and Mg at both soil depths and with the available S at 0–20 cm. The FFB yield of LYOPPs was positively and significantly correlated with the available P and S at the 0–20-cm soil depth and with the available N and P at the 20–40-cm soil depth. Except for a negative correlation (p < 0.05) with exchangeable Ca at the 20–40-cm soil depth, the FFB yield in HYOPPs had no significant correlation with the available soil nutrients at both depths. The FFB yield of LYOPPs had a positive significant (p < 0.01) correlation with the leaf P and K concentrations, while the yield of HYOPPs had a negative correlation (p < 0.01) with the leaf P. Fertilizer accounts for a large part of the on-farm cost in oil palm plantations, and an evidenced approach for fertilizer management based on nutrient contents and ratios in the soil and in the plant is useful for sustainable and profitable production of palm oil.

Spring barley performance benefits from simultaneous shallow straw incorporation and top dressing as revealed by rhizotrons with resealable sampling ports

Plant residues with larger carbon (C) to nitrogen (N) ratios can stimulate microbial growth and thereby protect soil nutrients from leaching. In poorly fertilized soil, excessive immobilization may limit nutrient availability and thus plant growth. Little is known about the impact of a shallow straw incorporation on soil microbial regulation of top-dressing fertilizer nutrients and spring crop establishment. We aimed to evaluate if wheat straw in combination with mineral fertilizer has more positive effects on plant performance than mineral fertilization alone and if this relates to changes of the extractable C:N:P ratio and microbial activity close to the roots. In order to conduct small-scale sampling with minimal disturbance during growth of spring barley (Hordeum vulgare L.), we developed rhizotrons with resealable ports. Rhizotrons were filled with loamy-sandy soil and fertilized with an equivalent of 150 kg N and 80 kg P ha−1. Half of the rhizotrons received the top dressing together with 4500 kg wheat straw-C ha−1. Throughout a 90-day greenhouse experiment, we analyzed soil C:N:P dynamics, and carbon dioxide (CO2) and nitrous oxide (N2O) emission, together with microbial biomass, selected bacterial genes (abundance), and transcripts (activity) in bulk and root-affected soil at multiple times. We focused on nitrifiers and denitrifiers and linked our data to barley growth. Interactions between straw and roots caused shifts towards larger C:P and C:N ratios in root-affected soil. These shifts were associated with increased 16S rRNA transcripts and denitrifier activities. Straw increased microbial biomass by 124% in the topsoil and at the same time increased root biomass by 125% and number of tillers by 80%. We concluded that microbial activation at the root-straw interface may positively feed back on soil nutrient regulation and plant performance. Further research has to evaluate if plant roots actively prime mining of previously immobilized nutrients in the straw detritusphere or if effects of pathogen suppression and growth promotion are dominating.

Quantitative and qualitative analysis of bottle gourd (Lagenaria siceraria): Impact of organic liquid fertilizer

At present, organic farming practices are getting more attention around the world owing to their sense of nutrition. Interestingly, nutrition refers to the taking of nutrients from food and utilizing for growth and molecular metabolism. Currently, organic farming involves the judicious combination of green manures, animal manures, bio-fertilizer, bio-botanical pesticides and crop rotations as well as crop residues. Among them, Panchakavya, Bijamrutha and Jivamrutha have come in to the line of natural agriculture. Therefore, the present study explored the bottle gourd (Lagenaria siceraria) growth along with these products for various treatments. In this bottle gourd, three different components were used for Panchagavya, Beejamrutha and Jeevamrutha at ten different concentrations. Along with this, one control was maintained for this plant. Various morphological parameters were used to identify plant growth such as plant height, root length, shoot length, and flowers count. Finally, harvested vegetables are used for quality analysis such as ascorbic acid, vitamin-C, phenolic compounds, antioxidants and nutrient analysis. From this study, plants using organic fertilizers shows significantly increased nutrient content and plant growth compared to control. The combination of Panchakavya + Bijamrutham + Jeevamrutha achieves excellent growth with eco-friendly and low cost liquid fertilizer nutrient enrichment.

Effects of coffee husk and cocoa pods biochar on the chemical properties of an acid soil from West Cameroon

ABSTRACT Evaluation of liming and fertility properties of biochar on acid soil was studied in this work. Selected soil properties such as pH, electrical conductivity (EC), exchangeable acidity (Ex Ac), exchangeable Al (Ex Al), exchangeable Fe (Ex Fe), available P and, soil organic carbon (SOC) were examined under the effect of biochar amendments. The acid soil was treated with biochar issued from coffee husk (CH) and cocoa pods (CP) pyrolyzed at 350°C and 550°C for 4 hours at amendment rate of 0, 20, 40 and 80 g kg−1 and an incubation time of 7, 14, 30, 40 and 60 d. Biochar amendments significantly increased soil pH, soil EC with respect to control and decrease in exchangeable acidity was observed. Results show that biochar improved available P in acid soil, though re-adsorption occurred with increasing incubation time. A significant increase in SOC is observed as compared to control. The impact of biochar on these acid soil chemical properties is due to the properties which are dependent on the biochar type and pyrolysis temperature. Thus, biochar can play the dual role of a liming agent and a source of P fertilizer nutrients.

Vertical and temporal variations of soil bacterial and archaeal communities in wheat-soybean rotation agroecosystem.

Soil microbes are an essential component of terrestrial ecosystems and drive many biogeochemical processes throughout the soil profile. Prior field studies mainly focused on the vertical patterns of soil microbial communities, meaning their temporal dynamics have been largely neglected. In the present study, we investigated the vertical and temporal patterns of soil bacterial and archaeal communities in a wheat-soybean rotation agroecosystem at a depth of millions of sequences per sample. Our results revealed different vertical bacterial and archaeal richness patterns: bacterial richness was lowest in the deep soil layer and peaked in the surface or middle soil layer. In contrast, archaeal richness did not differ among soil layers. PERMANOVA analysis indicated that both bacterial and archaeal community compositions were significantly impacted by soil depth but unaffected by sampling time. Notably, the proportion of rare bacteria gradually decreased along with the soil profile. The rare bacterial community composition was the most important indicator for soil nutrient fertility index, as determined by random forest analysis. The soil prokaryotic co-occurrence networks of the surface and middle soil layers are more connected and harbored fewer negative links than that of the deep soil layer. Overall, our results highlighted soil depth as a more important determinant than temporal variation in shaping the soil prokaryotic community and interspecific interactions and revealed a potential role of rare taxa in soil biogeochemical function.

Understanding the Effect of Different Abiotic Stresses on Wild Marigold (Tagetes minuta L.) and Role of Breeding Strategies for Developing Tolerant Lines.

Wild marigold has a growing demand for its essential oil in the flavor and fragrance industries. It can be grown over a broad range of climates, but the changing climatic conditions lead to abiotic stresses, thus restricting its productivity. Abiotic stresses at elevated levels result in the reduction of germination, growth, and essential oil quality of wild marigold leading to heterogeneous and inferior grades of “Tagetes oil.” Drought, salinity, and heavy metal stress at elevated levels have common effects in terms of ROS formation, which are the major cause of growth deterioration in wild marigold. Temperatures above 35°C inhibit seed germination. Irradiance stress reduces the biomass and essential oil yield. Waterlogging adversely affects the survival of wild marigold in high rainfall regions. The application of plant nutrients (fertilizers) modulates the biomass and essential oil yield. Wild marigold employs multiple tolerance mechanisms to cope up with the adverse effects of abiotic stresses such as the increased activity of antioxidants to maintain cellular redox homeostasis, enhanced lipid peroxidation in the cell membrane to maintain cell wall architecture, production of secondary metabolites, and accumulation of osmolytes. In this review, we tried to understand how abiotic stresses affect wild marigold. Understanding the physiological changes and biochemical characteristics of stress tolerance will contribute to the development of stress-tolerant lines of wild marigold.

QUEFTS Model-based Estimation of the Nutrient Requirements and Fertilizer Recommendation for Chinese Onion

Accurate estimation of the nutrient requirements of Chinese onion is essential to increase its nutrient utilization efficiency and yield. In this study, the yield and nutrient uptake data were collected from major Chinese onion growing regions during 2001 to 2018, and the relationship between Chinese onion yield and nutrient uptake was evaluated using the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model. The QUEFTS model predicted the linear-parabolic platform curve of the balanced nutrient uptake of Chinese onion and estimated the demand of nitrogen (N), phosphorus (P), and potassium (K) for the potential target yields ranging from 40 t/ha to 120 t/ha. The nutrients required for the target yield increased linearly before reaching 60% to 70% of the potential yield. Nutrient requirements for producing 1 t of Chinese onion were 1.91 kg N–0.28 kg P–1.71 kg K. The corresponding nutrient internal efficiency (IE, yield per unit nutrient uptake) was 524.6 kg/kg, 3585.7 kg/kg, and 584.3 kg/kg for N, P and K, respectively. Subsequently, a nutrition decision-making software, Nutrient Expert (NE), for the Chinese onion was developed based on the improved QUEFTS model. Field verification studies for NE fertilizer recommendation were conducted in multiple Chinese onion growing plots for 2 consecutive years. Results showed that the QUEFTS model can be used to accurately estimate the nutrient requirements for Chinese onion within a defined range of target yield.

The Development of Hydroponic Nutrient Solutions Control Using Fuzzy and BPNN for Celery Plant

As the increasing number of human populations, most live in urban areas with limited farmlands. Hydroponic is one of the solutions to grow crops in urban areas. Electrical Conductivity (EC) and scale of acidity (pH) in the hydroponic nutrient solution are the important things to be controlled. Controlling EC and pH in hydroponic can increase the quantity and quality of the crop. This research suggested a new method to merge fuzzy and Backpropagation Neural Network (BPNN) to control nutrient solutions in a Nutrient Film Technique hydroponic, with sensors EC and pH as input. The training data of BPPN are obtained from the implementation of the fuzzy technique. Controlling nutrient solutions can use fuzzy methods, but it has a weakness: use greater power because sensors require continuous detection. By using BPNN method, sensors only detect once to perform the same control action. In this research, the outputs of both methods are the duration of pumps in active conditions to optimize the nutrient solution. Based on experiments, the best BPNN model has eight hidden layers with a learning rate of 0.8. The result accuracies which had been obtained by alkaline solution (pump A) was 90.77 %, 91.93% for acid solution (pump B), and 91.13% for nutrient fertilizer (pumps C and D). The result showed that the use of power for BPNN is less than fuzzy. The average total power used for BPNN method is 68.43% lower than the fuzzy method.

Biochar and compost amendments to a coarse-textured temperate agricultural soil lead to nutrient leaching

Organic soil amendments benefit agricultural soils depleted in soil organic matter because they improve soil chemical and biological properties. Biochar and compost, used as organic amendments, differ in their contents of total vs. available nutrients and may therefore differ in their effects on soil properties. The effects of these amendments have seldom been assessed in coarse-textured temperate soils and in no-tillage agriculture. In this study, we conducted a 6-month laboratory experiment with a coarse-textured temperate soil with a history of conventional farming to determine the effects of biochar, compost, and their combination, which were spread evenly on the soil surface, on microbial activity and biomass, and nutrient release and leaching. Both biochar and compost increased microbial activity and nutrient release compared to the no-addition treatment, but compost effects were relatively short term (<two months), and biochar effects were relatively long term (>six months). Biochar and compost had additive effects on all properties when added in combination. Biochar addition to soil increased soil pH, microbial biomass, and the abundance of fungi, G+ bacteria, and actinobacteria after 6 months of incubation compared to the compost treatment and the no-addition treatment. Although biochar was expected to reduce loss of nutrients through leaching, the short exposure time and disturbance of the soil probably hindered its capacity to adsorb nutrients and to thereby limit leaching; as a consequence, the biochar acted only as a slow-release nutrient fertilizer during the 6-month incubation.

Nutrient fertilization by dogs in peri‐urban ecosystems

Abstract (Semi‐)natural ecosystems provide many important benefits to nature and people, but are often located near populated and urbanized areas across the globe. During recreational activities, many people bring dogs into peri‐urban forests and nature, but their nutrient inputs per unit space and time via dog faeces and urine into ecosystems remain scarcely quantified. Here, we estimate net fertilization rates of dogs in peri‐urban ecosystems, with a focus on nitrogen (N) and phosphorus (P) because of their evident effects on plant biodiversity. We used 487 direct‐count censuses over 1.5 years to collect accurate dog abundance data per hectare per year in four sites in peri‐urban forests and nature reserves in Belgium. Based on estimated dog densities and a systematic literature search of nutrient concentrations in urine and faeces, we calculate N and P fertilization rates from urine and faeces deposits, also propagating uncertainty and variability in these estimates. We find that canine N and P fertilization rates on average amount to 11 kg N (more or less equally from urine and faeces) and 5 kg P (predominantly from faeces) per hectare per year, respectively. These estimated amounts are substantial when compared to atmospheric inputs of N and extractable amounts via traditional nature management (e.g. mowing and hay removal). Our estimated dog N and P fertilization rates in peri‐urban forests and nature are substantial. Such levels of nutrient inputs may considerably influence biodiversity and ecosystem functioning, and co‐determine restoration outcomes. Our results underpin the need for managers and policy makers to more often (i) consider currently neglected nutrient inputs by dogs in management plans and restoration goals, (ii) communicate to dog walkers the role of their dog as ‘fertilizer’ and highlight the necessity to remove at least canine solid faecal waste, (iii) in sensitive oligotrophic ecosystems with species adapted to nutrient‐poor soils, establish nearby off‐leash dog parks, enforce the use of short leashes and/or apply dog bans such that high dog abundances can be avoided.

Economically Optimal Rates and Nutrients Use Efficiency Indices of Maize to the Application of Different Rates of Nutrients in Central Rift Valley of Ethiopia

The use of balanced fertilizers in adequate amount is very important to increase crop productivity and production in Ethiopia. The study was executed to quantify maize (Zea mays L.) grain yield response to different rates of nitrogen (N), phosphorus (P), potassium (K) and sulfur (S) under balanced fertilization of other nutrients. On farm trials were conducted at seven sites on 8 farmers’ fields in Negele Arsi districts, west Arsi zone of Oromia region for three consecutive cropping seasons (2014-2016). Six rates of N, P, S and eight rates of K treatments established separately for each nutrient were laid out in randomized complete block (RCB) design with three replicates per farm. Nutrient response function modelling showed that 184, 20 and 80 kg•ha−1 were the agronomic optimum rate for N, P, and K, respectively. Mean agronomic efficiency (AE) of N, P and K were recorded at the lower rates of these nutrients, application of 46, 10 and 20 kg•ha−1 N, P and K resulted in 19.1, 61.0, and 24 kg additional grain yield•kg−1 N, P and K, respectively. Also, the mean partial factor productivity (PFP) of N, P and K were 77.6, 370 and 158 kg additional grain•kg−1 applied N, P and K respectively. Economically optimal rate (EOR) of N, P and K were 48 - 114 kg•ha−1 N with CP 8 - 3.5, 12 - 20 kg•ha−1 P with CP 18 - 4.5 and 32 - 53 kg•ha−1 K with CP 8-4, from these rates net returns of US$487.23 - 143.30, US$698.16 - 498.3 and US$359.31 - 193.63 could be obtained respectively. To conclude, application of 84, 12 and 40 kg•ha−1 N, P and K could be recommended for the production of maize.

Nutrient accumulation in fruits and grains of black pepper at different ripening stages

ABSTRACT: Nutrients accumulation in plants/fruits varies according to the crop development stage and its quantification is important to determine nutrients exportation for fertilization planning and nutrient balancing. This study determined the accumulation of nutrients in different parts of Piper nigrum ‘Bragantina’ spikes harvested at two ripening stages (still-green and red-colored spikes). Assessments in separate parts of still-green spikes (fruits and peduncles) as well as in red-colored spikes (grains, flesh and peduncles) were performed. Piper nigrum spikes were harvested, dried, and the parts were thereafter separated for chemical analysis. N and Mn were the macro and micronutrient most accumulated in the fruits of still-green spikes and in the grains of red-colored spikes, while K and B were most accumulated in the other parts of black pepper assessed, regardless of the ripening stage. The process of removing the flesh from the fruits for white pepper production led to a difference in nutrient concentration and accumulation between the fruits of still-green spikes and the grains of red-colored spikes. A significant contribution of nutrient input can be achieved by maintained flesh and peduncles in the crop area, decreasing the dependence of external fertilizers and thus contributing to a more sustainable agriculture.

Evaluation of Pigeon Pea Varieties and Cultivars for Soil Nutrient Addition and Fertility Level in Case of Fadis District of Eastern Hararghe Zone

The study was conducted at Fadis research station of Fadis district in the eastern hararghe zone during 2019, 2020 and 2021. Pigeon pea is a deep-rooted and drought tolerant grain legume that adds substantial amount of organic matter to the soil and has the ability to fix up to 235 kg N/ha and produces more N per unit area from plant biomass than many other legumes. Seven pigeon pea cultivars and four variety were used as treatment materials. The objective of study was to quantify amount of soil nutrient (N) obtained/fixed because of the pigeon pea cultivars or varieties. Treatments of the experiments were pigeon pea cultivars and variety, ELR16555, ILRI16526, ELR16524, ILRI 11575, Tsegas variety, Local, Danda’a variety, ELR 11566, Belabas, ELR 16537 and ELR 11563 respectively. The experiment was laid out in randomized complete block design with three replications of each. Data like Plant height, Total biomass, canopy area, soil sample before and after were collected and analyzed using SAS version 9.1 (SAS, 2002). Different Pigeon pea cultivars shows highly significant difference among the treatment in terms of plant height at 5% significance level. Different Pigeon pea cultivars and variety shows highly significant difference among the treatment in terms of plant height at 5% significance level (table 2). The highest plant height (331.5cm) was recorded from Belabas variety followed by Tsegas (308.6cm) and Danda’a variety (294.4cm). On the other hand, ELRI 16555 cultivars shows the shortest plant height (213.0cm) followed by local check (221.7cm). The highest biomass (125000 kg/ha) was recorded from Tsegas variety and the lowest biomass (45000 kg/ha) was recorded from ELRI 16537 cultivars. The highest %OC, %TN and available phosphorus and CEC were recorded from the soil under the Tsegas pigeon pea variety followed by Belabas pigeon pea variety. On the contrary the lowest were recorded from ELR11575 and local check. Generally, from the result it is possible to conclude that the highest biomass yield and almost all of the highest desired soil parameters were recorded by Tsegas variety and it is possible to recommend for the farmers of Fadis District and similar agro- ecologies.