Frontiers in Agronomy最新文献

{"title":"Establishing phosphorus critical values for tomato (Solanum lycopersicum) fertilization with phosphate fertilizers on the Sudan savanna soils using three soil phosphorus extraction methods and field experimentation in Kano State, Nigeria","authors":"Yahaya Mohammad Yusuf, D. K. Madukwe, F. Kebede","doi":"10.3389/fagro.2023.1181045","DOIUrl":"https://doi.org/10.3389/fagro.2023.1181045","url":null,"abstract":"Phosphorus (P) is an essential nutrient for tomato (Solanum lycopersicum L.) production, as it stimulates root growth by improving water use efficiency and nutrient uptake. It also helps control the metabolic processes of ATP (energy), sugars, and nucleic acids. Therefore, it is imperative to effectively manage the phosphorus requirements of tomatoes to bolster their productivity. The objective of this study was to evaluate the effectiveness of three different soil P testing methods that are suitable for the soils of Kano State, Nigeria, and to develop a critical P-value for fertilizer recommendations for tomatoes. Accordingly, sixty topsoil samples were collected for soil available P testing according to the Bray II, Mehlich 3, and Olsen methods. Moreover, to establish the phosphorus critical value (Pc) for tomatoes, a field experiment was conducted with seven different rates of P using triple super phosphate fertilizer (TSP), viz., 0, 15, 30, 45, 60, 75, and 90 kg P/ha, laid out in a randomized complete block design with three replications on 15 experimental sites representing the various agroecological zones of the state. Phosphorus fertilizer was applied and incorporated into the soil 1 week before tomato transplanting. Then, soil samples from 0 to 20 cm depth were taken 3 weeks after transplanting from all the plots across the experimental sites for separate Mehlich 3, Bray II, and Olsen extractable P analysis to determine the critical soil P (Pc) test. The study revealed that available P was varied and increased in the order of Olsen (2.19 ppm)< Mehlich 3 (5.37 ppm)< Bray II (5.44 ppm), and the Mehlich 3 and Bray II extraction methods were strongly correlated, whereas Olsen underestimated the available P, showing a weak correlation with both Mehlich 3 and Bray II. Furthermore, the study showed that phosphorus critical (Pc) values were 17.00, 14.00, and 4 ppm for Mehlich 3, Bray II, and Olsen respectively. Finally, Bray II was a more reliable method for estimating the available P on moderately acid soils as it showed the highest correlation r = 0.83 with the relative yield of the tomatoes and, therefore, was the most effective method for developing the equation for the soil test-based phosphatic fertilizer recommendation for maximizing tomato production in the soils of Kano State. Hence, the equation developed for the P fertilizer recommendation (Pr) for tomatoes in Kano State was found to be “Pr (kg P2O5 ha−1) = (14.0 − Pi) × 9.02”.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43252390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Agronomic and environmental aspects of organo-mineral fertilizers produced with a by-product of the intermediate process of tanning","authors":"F. Lima, A. O. Silva, Helen C. S. Amorim, Eduardo Sobrinho Santos Figueredo, Rafael Marta Carbone Carneiro, Madeliny Saracho Jara, M. Carneiro, L. Guilherme","doi":"10.3389/fagro.2023.1215448","DOIUrl":"https://doi.org/10.3389/fagro.2023.1215448","url":null,"abstract":"The by-product of the intermediate process of tanning (BPIPT) can be used in the manufacturing of environmentally-friendly organo-mineral fertilizers (OMF). However, the presence of potentially toxic elements (e.g., chromium, Cr), can hinder the use of BPIPT in agriculture. This study aimed: i) to evaluate soil chemical and biological properties following the application of fertilizers produced with a BPIPT, in contrast to other OMF produced with traditional organic matrices; and ii) to assess the impacts of such products on wheat growth and nutrition.Samples (0-0.2 m) of two Oxisols [Red-Yellow Latosol (LVAd) and Red Latosol (LVd)] were used in this study, consisting of two experiments (with five treatments and five replicates) using different OMF, in a sequence: 1) incubation of fertilizers in soil samples for 30 days, and 2) wheat cultivation (30 days) after the fertilizer incubation. The treatments consisted of an arrangement of mineral fertilizers based on nitrogen, phosphorus, and potassium (NPK fertilizers), associated with OMF based on BPIPT (OM-IPT and OM-IPT+S) or commercial manure (OM-CM and OM-CM+S), with or without sulfur (S), and a control treatment. Elemental availability in soils and microbial attributes were determined after the incubation of the OMF in the soils. After wheat cultivation, plant biomass, nutritional composition, β-glucosidase activity, and fluorescein diacetate hydrolysis (FDA) were measured.The application of BPIPT-derived OMF in the present study increased available Cr fraction contents in both soils. However, OM-IPT caused low soil acidification, enhanced wheat growth and nutrition, and stimulated microbial activity in soils (FDA and β-glucosidase), thus evidencing the agronomic and environmental benefits of this OMF and their potential to contribute to a cleaner, more sustainable agriculture.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42419544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Philippine-sourced clay particles as coating agents of cacao pods and carrier of entomopathogen against cacao pest, Helopeltis bakeri Poppius","authors":"Sharin C. Albacete, D. Amalin, Thaddeus M. Carvajal, J. Wise","doi":"10.3389/fagro.2023.1213131","DOIUrl":"https://doi.org/10.3389/fagro.2023.1213131","url":null,"abstract":"Evaluation of the efficacy of clay particles as a coating agent of cacao pods and carrier of entomopathogen, Metarhizium anisopliae Sorokin, was conducted for the control of cacao mirid bug (CMB), Helopeltis bakeri Poppius. Choice and no-choice tests were performed to evaluate Philippine-sourced clay particles as a coating agent of cacao pods to deter CMB feeding, in comparison with the commercially available particle film (US kaolin Surround®). To determine the most efficient local clay particles in protecting the pods from CMB feeding, six (6) treatments were evaluated namely, Philippine-sourced kaolin (PH kaolin), zeolite (PH zeolite), bentonite (PH bentonite), US kaolin, water (negative control), and a commercial synthetic insecticide thiamethoxam (Actara®) (positive control). All treatments were subjected to choice and no-choice tests. Among the Philippine clay particles tested in both tests, PH zeolite showed significant coating and deterred CMB from feeding. Since the US Kaolin and zeolite showed significant feeding deterrent effects on CMB, these treatments were tested as carriers of entomopathogenic fungi, M. anisopliae, including water (negative control) and thiamethoxam. Results showed that zeolite is a good carrier of the spores of M. anisopliae as its effects to deter CMB feeding started 24 hours after exposure. This was confirmed by positive M. anisopliae extraction from dead CMB through potato dextrose agar (PDA) plating.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43436951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the effects of APSIM model configuration on model outputs across different environments","authors":"R. Chapagain, T. Remenyi, N. Huth, Caroline L. Mohammed, Jonathan J. Ojeda","doi":"10.3389/fagro.2023.1213074","DOIUrl":"https://doi.org/10.3389/fagro.2023.1213074","url":null,"abstract":"Soil type plays a major role in nutrient dynamics and soil water which impacts crop growth and yield. The influence of soil characteristics on crop growth is usually evaluated through field experimentation (in the short term) and through crop-soil modelling (in the long-term). However, there has been limited research which has looked at the effect of model structural uncertainty of model outputs in different soil types.To analyze the impact of soil inputs on model structural uncertainty, we developed eight model structures (a combination of two crop models, two soil water models and two irrigation models) within the Agricultural Production Systems sIMulator (APSIM) across three soil types (Ferralsols, Alisols and Chernozems). By decomposing the mean proportion of variance and simulated values of the model outputs (yield, irrigation, drainage, nitrogen leaching and partial gross margin) we identified the influence of soil type on the magnitude of model structural uncertainty.For all soil types, crop model was the most significant source of structural uncertainty, contributing >60% to variability for most modelled variables, except irrigation demand which was dominated by the choice of irrigation model applied. Relative to first order interactions, there were minimal (<12%) contributions to uncertainty from the second order interactions (i.e., inter-model components). We found that a higher mean proportion of variance does not necessarily imply a high magnitude of uncertainty in actual values. Despite the significant impact of the choice of crop model on yield and PGM variance (contributing over 90%), the small standard deviations in simulated yield (ranging from 0.2 to 1 t ha-1) and PGM (ranging from 50.6 to 374.4 USD ha-1) compared to the mean values (yield: 14.6 t ha-1, PGM: 4901 USD ha-1) indicate relatively low actual uncertainty in the values. Similarly, the choice of irrigation model had a contribution of over 45% to variance, but the relatively small standard deviations ranging from 11 to 33.3 mm compared to the overall mean irrigation of 500 mm suggest low actual uncertainty in the values. In contrast, for the environmental variables- drainage and nitrogen leaching, the choice of crop model had contributions of more than 60% and 70% respectively, yet the relatively large standard deviations ranging from 7.1 to 30.6 mm and 0.6 to 7.7 kg ha-1 respectively, compared to the overall mean values of drainage (44.4 mm) and nitrogen leaching (3.2 kg ha-1), indicate significant actual uncertainty.We identified the need to include not only fractional variance of model uncertainty, but also magnitude of the contribution in measured units (e.g. t ha-1, mm, kg ha-1, USD ha-1) for crop model uncertainty assessments to provide more useful agronomic or policy decision-making information. The findings of this study highlight the sensitivity of agricultural models to the impacts of moisture availability, suggesting that it is important to give more attention","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43721474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the early phases of epidemics by Phakospora pachyrhizi in Brazilian soybean","authors":"B. Kassie, D. Onstad, L. Koga, Tim Hart, R. Clark, G. W. van der Heijden","doi":"10.3389/fagro.2023.1214038","DOIUrl":"https://doi.org/10.3389/fagro.2023.1214038","url":null,"abstract":"Asian soybean rust, caused by the biotrophic basidiomycete Phakospora pachyrhizi, is a foliar disease that often causes considerable damage to soybean crops. The purpose of our work was to create a mechanistic model that can reliably represent epidemics of ASR in commercial soybean fields in Brazil. The most important inputs for the model are weather data (observations and forecast) and the initial observation of disease (or uredospore arrival). Our focus is on the first two or three cycles of infection after immigration into a soybean field. The model includes state variables for latent, infectious and senesced lesions, disease severity, uredospores, and soybean leaf area. Processes modeled include maturation through the latent and infectious periods, germination, sporulation, and processes affecting uredospores in the canopy. The model results were tested against field observations from trials at four locations in Brazil for the 2019/2020 growing season. The predictions generally matched the daily dynamics of disease progress in the field trials. The predictions reproduced the observed severity well with R2 value of 0.84. This high correlation indicates that our model is accurate enough to be used as a tool to predict the dynamics of ASR epidemics during the first few cycles after uredospore invasion into a soybean field. A sensitivity analysis was performed that showed that the model is sensitive to time and duration of the initial spore arrival. This indicates that spore traps or other observations should measure not only the first day of arrival but also subsequent days.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48480925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic analysis of Sinorhizobium meliloti LPU63, an acid-tolerant and symbiotically efficient alfalfa-nodulating rhizobia","authors":"J. H. Cafiero, María Salvetti Casasco, M. Lozano, C. Vacca, Silvina Laura López García, W. Draghi, A. Lagares, M. F. Del Papa","doi":"10.3389/fagro.2023.1175524","DOIUrl":"https://doi.org/10.3389/fagro.2023.1175524","url":null,"abstract":"The growth and persistence of alfalfa (Medicago sativa), a perennial legume capable of producing high yields of high-quality forage, is reduced in moderately acidic soils. The low performance of alfalfa at low pH is due to numerous factors that affect the host plant, their rhizobia, and the symbiotic interaction. Sinorhizobium meliloti LPU63 was isolated from acid topsoil (in Argentina) and showed to be a highly competitive and efficient N2-fixing rhizobium under both neutral and moderately acidic soil conditions. In this study, we obtained a draft of the LPU63 genome sequence using Illumina HiSeq4000. The whole genome phylogenetic analysis confirmed the taxonomic position of LPU63 as a S. meliloti strain and the multilocus sequence analysis confirmed that LPU63 is not related to the strains used in Argentina in bioformulations. The genomic analysis showed that beyond the canonical chromosome, pSymA, and pSymB, LPU63 strain has an accessory plasmid that codes for a repABC origin of replication and a conjugative T4SS, suggesting that this plasmid could be self-transmissible. In addition, the complete denitrification pathway (i.e., the gene clusters nap, nir, nor, and nos), including napC and nosZ, which could be used as an alternative respiration route under hypoxic conditions with moderate N2O emissions was found. Also, genes associated with plant growth-promoting activities (PGPR) and the degradation of phenylacetic acid (PAA) were identified. LPU63 is a highly melanogenic strain, a property that could enhance its survival under soil conditions, and the genome data showed a particular arrangement of the genes involved in melanin production. The information regarding LPU63 activities compatible with plant-growth promotion phenotypes, together with other characteristics mentioned here (melanin production, potential moderate N2O emissions), constitute the basis of future experiments toward the rational design of a novel bioinoculant for the environmentally sustainable production of alfalfa.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43507285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reinforcing the Hydrosocial Cycle to foster water governance and stakeholders’ interdependence in urban agroecosystems: a local test in Benidorm, Spain","authors":"S. Ricart, R. Villar, M. Hernández-Hernández, Antonio M. Rico-Amorós, J. Olcina-Cantos, C. Baños","doi":"10.3389/fagro.2023.1057211","DOIUrl":"https://doi.org/10.3389/fagro.2023.1057211","url":null,"abstract":"The Hydrosocial Cycle (HSC) has been widely applied and discussed as a consolidated research line to rethink the contemporary challenges that condition the urban and agroecosystem nexus. However, additional research directions are still open to guide policy and decision-makers in reinforcing stakeholders’ engagement and interaction to resolve tensions between water demands. This perspective paper suggests updating the HSC approach to improve the analysis of stakeholder interaction when addressing water scarcity in waterscapes. After briefly review the most relevant contributions of the HSC approach in the last two decades, we develop a preliminary framework to reinforce stakeholders’ interdependence analysis by designing a questionnaire to synthesize five main behavioral patterns conditioning stakeholders’ interactions: relevance, representativeness, recognition, assessment, and collaboration. Then, each pattern is organized in a triple-loop approach: to be, to do, and to share to characterize the mutual (mis)understanding of the stakeholders. The results of its application to Benidorm (south of Spain), a mass-tourism destination coexisting with rural development in tension for water supply, exemplified how 1) most stakeholders consider themselves important, but some of them are unaware of the role of others, 2) all stakeholders receive a higher punctuation in terms of functions rather than actions, and 3) all stakeholders agree on the benefits of the predisposition of parties (willingness) to achieve agreements in the short or medium term. Future research should consider how to address the lack of representativeness and power imbalance together with mechanisms to reinforce longitudinal studies in which actions from stakeholders could be contrasted.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42349276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A newly isolated cotton-infecting Polerovirus with cryptic pathogenicity encodes a weak suppressor of RNA silencing","authors":"M. Akinyuwa, Bailee K. Price, K. Martin, Sung-Hwan Kang","doi":"10.3389/fagro.2023.1235168","DOIUrl":"https://doi.org/10.3389/fagro.2023.1235168","url":null,"abstract":"Cotton is a multipurpose crop grown globally, including the United States. Cotton leafroll dwarf virus (CLRDV), a phloem-limited virus (Solemoviridae) transmitted by aphids, causes significant economic losses to cotton cultivation. CLRDV strains (CLRDV-typical and atypical) that were previously prevalent in other countries cause severe symptoms leading to high yield loss. Recently, a new isolate of CLRDV (CLRDV-AL) has been characterized from infected cotton plants in Alabama that are often asymptomatic and difficult to detect, implying a low titer and pathogenicity within the host. Different pathogenicity among certain strains within the same species often correlates with both environmental and molecular factors. Thus, better management and control of the vector-borne disease can be achieved by elucidating host-pathogen interaction, such as host immune response and pathogen counter-response. In this study, we demonstrate the ability of CLRDV-AL to suppress a major host defense response known as RNA silencing and compare the potency of silencing suppression to other strains of the same virus. Also, we discuss the difference in pathogenicity among them by evaluating the observations based on the amino acid variation within the functional domain. Our study provides and suggests a future direction for specifying the strategy to mitigate potential cotton disease severity.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43713388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging possibilities in the advancement of herbicides to combat acetyl-CoA carboxylase inhibitor resistance","authors":"Bikash Kumar Rajak, Priyanka Rani, Pranabesh Mandal, R. S. Chhokar, Nitesh Singh, Durg Vijay Singh","doi":"10.3389/fagro.2023.1218824","DOIUrl":"https://doi.org/10.3389/fagro.2023.1218824","url":null,"abstract":"Acetyl-CoA carboxylase (ACCase: EC 6.4.1.2) is one of the essential biotins containing enzymes required by plants for fatty acid synthesis and elongation. The unique enzyme is present in its homomeric form in all the Gramineae family, making it a suitable target for developing herbicides selectively against weeds of the Gramineae family. One such example is infestation of Phalaris minor in winter wheat crop fields, where aryloxyphenoxypropionates (FOP); cyclohexanediones (DIM) and phenyl pyrazoline (DEN) group of ACCase inhibiting herbicides are used. However, the increasing number of ACCase herbicide resistant weed populations has compelled agro-scientists to seek varied possibilities for weed control, through Integrated Weed Management (IWM) strategies. Developing new potential herbicides to regain sensitivity in weeds could be an approach to weed control. The current advancement in computational techniques could be of aid in developing new herbicide-like molecules by exploring the genomics, proteomics and structural details of catalytic sites of herbicide action in crops as well as weeds.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45394332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Poultry litter and cow dung biochar as P sources for cowpea cultivation in two Ghanaian soils","authors":"E. Nartey, N. Sulemana, Awudu Razak, T. Adjadeh, A. M. Akumah, C. Amoatey, M. Abekoe","doi":"10.3389/fagro.2023.1233255","DOIUrl":"https://doi.org/10.3389/fagro.2023.1233255","url":null,"abstract":"The main constraint to cowpea, Vigna unguiculata, production in West Africa is unavailability of applied phosphorus due to ligand exchange with clay minerals and precipitation reactions facilitated by low pH and low organic matter.To overcome this challenge, cow dung biochar (CB) and poultry litter biochar (PB) were applied as P sources for cowpea cultivation in Plinthustult and Kandiustalf soil in Ghana. The biochar types and triple super phosphate (TSP) were applied to meet the standard phosphorus requirement (SPR) and ½ SPR of the soils. Basal K from KCl was added to the TSP treatment. In addition to a non-amended soil, the treatments were triplicated and arranged in a completely randomized design in a screen house for an efficacy trial using cowpea as the test crop. Moisture content was maintained at 80% field capacity.Hundred cowpea seed weight was 20.3 g and 19.6 g for the TSP-amended Plinthustult at SPR and ½ SPR, respectively. This increased to 25.1 g and approximately 27 g at SPR and ½ SPR in the CB- and PB-amended Plinthustult, respectively. Hundred seed weight for TSP at both rates was similar in the two soils. The PB-amended Kandiustalf at SPR had seed with a weight of 27.02 g, 1.1 g heavier than the ½ SPR. The CB-amended Kandiustalf at both rates had 100 seeds weighing 25 g. Residual available P was 334.2 mg/kg and 213.2 mg/kg at SPR and ½ SPR, respectively, in the Plinthustult as opposed to a paltry 2.5 mg/kg at SPR in the TSP counterpart. The study recommends for the two biochar types to be applied at ½ SPR.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46877189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}