Phytophthora kernoviae—pathogen of beech and rhododendron, also occurring on other trees and shrub species including oaks, and holm oak. Distribution is confined to the UK. Phytophthora megakarya—one of the species causing black pod of cacoa, and is probably responsible for the greatest cocoa crop loss in Africa.Phytophthora megakarya is an oomycete plant pathogen that causes black pod disease in cocoa trees in west and central Africa. This pathogen can cause detrimental loss of yield in the economically important cocoa industry, worth approximately $70 billion annually. It can damage any part of the tree, causing total yield losses which can easily reach 20-25%. A mixture of chemical and cultural ...Phytophthora megakarya has spread westwards from Cameroon through Nigeria and Togo, to the major cocoa producing countries of Ghana and Cote d'Ivoire, and southwards to Gabon and Equatorial Guinea. Phytophthora megakarya has become the main yield-limiting factor in cocoa production in the sub region, rapidly surpassing P. palmivora.This dataset contains a compilation of Phytophthora species found in sub-Saharan Africa. The primary source of data for Phytophthora species recorded in this …On the other end, several genome assemblies had high repeat content, namely, P. megakarya, Phytophthora hibernalis, and Phytophthora pinifolia contained 32.94, 32.46, and 33.00%, respectively. Fig. 1. Analysis of 31 Phytophthora species shows an abundance of repetitive elements. Species are shown in phylogenetic clade order; clade designations ...Cocoa [Phytophthora megakarya L.]) Septiana 1)* , Suskandini Ratih Dirmawati 1) , Rusdi Evizal 1) 1) Jurusan Agroteknologi Fakultas Pertanian Universitas Lampung, Jl. Prof. SoemantriEvaluation of the Epidemiological Factors Responsible for the Appearance of Phytophthora Palmivora and Phytophthora Megakarya, Causal Agent of Black Pods Disease in the Department of Méagui, Southwestern Côte D'ivoirePhytophthora megakarya is an increasingly important invasive pathogen of cocoa in West Africa, where it forms part of the black-pod disease complex together with the more widespread, but less aggressive, P. palmivora.Its purported centre of diversity, based on evidence from molecular studies and mating types, lies on the Cameroon-Nigeria border, from where it has spread throughout both ...Defense gene polymorphisms were identified which could contribute to pathogen recognition capacity. Cacao suffers significant annual losses to the water mold Phytophthora spp. (Oomycetes). In West Africa, P. megakarya poses a major threat to farmer livelihood and the stability of cocoa production.Oct 1, 1999 · Phytophthora megakarya is an important pathogen of cocoa in Africa. We used isozyme and RAPD markers to estimate the genetic diversity and structuring among 161 isolates, from the known distribution area of the fungus which corresponds to the cocoa belt in Ghana, Togo, Nigeria, Cameroon, Gabon and Sao Tome. The black rod disease of genus Phytophthora caused up to 20–25% loss (700,000 metric tons) in world cacao production. The role of tcGASA genes in conferring fungal resistance was also explored based on RNAseq data …Two well-established diseases cause the greatest losses: black pod rot, caused by several species of Phytophthora, and witches’ broom of cacao, caused by Moniliophthora perniciosa. Phytophthora megakarya causes the severest damage in the main cacao producing countries in West Africa, while P. palmivora causes significant losses globally.Effect of four strains of Trichoderma asperellum and Phytophthora megakarya infection on soluble phenol in leaves of cocoa seedlings. According to the Duncan test, means with the same letter are ...The species is listed as an alternative host for Phytophthora palmivora and P. megakarya in Ghana, both causing the black seed pod disease in cocoa trees (Opoku et al., 2002). Although there was no evidence of an increase of infection on the cocoa trees near the F. elastica trees, the authors suggest that further studies are needed to assess ...PDF | On Oct 1, 2014, J.B. Mbarga and others published A new oil-based formulation of Trichoderma asperellum for the biological control of cacao black pod disease caused by Phytophthora megakarya ...megakarya which is the most aggressive in the country (80% losses). This study was aimed at dete rmining the clonal resistance of six cocoa clones (IMC67, SCA12, TAFO79/501, TAFO79/467 ICS40 ...current name Phytophthora megakarya type material of Phytophthora megakarya: ATCC :42100, CBS :238.83, IMI :202077 NCBI BLAST name: downy mildews Rank: species Genetic code: Translation table 1 (Standard) Mitochondrial genetic code: Translation table 1 (Standard) Plastid genetic code: Translation table 11 (Bacterial, Archaeal and Plant Plastid)Feb 14, 2017 · Phytophthora megakarya (Pmeg) and Phytophthora palmivora (Ppal) cause black pod rot of Theobroma cacao L. (cacao). Of these two clade 4 species, Pmeg is more virulent and is displacing Ppal in ... Basic information. EPPO code: PHYTMG. Preferred name: Phytophthora megakarya. Authority: Brasier & Griffin. Taxonomy. Kingdom Chromista ( 1CHROK ) Phylum Oomycota ( 1PSDFP ) Class Oomycetes ( 1OOMYC ) Order Peronosporales ( 1PEROO )Phytophthora megakarya (Pmeg) and Phytophthora palmivora (Ppal) cause black pod rot of Theobroma cacao L. (cacao). Of these two clade 4 species, Pmeg is more virulent and is displacing Ppal in many cacao production areas in Africa. Symptoms and species specific sporangia production were compared when the two species were co-inoculated onto pod pieces in staggered 24 h time intervals. Pmeg ...The black pod disease caused by Phytophthora megakarya is responsible for 80% of the cocoa production loss in Cameroon. To assess the resistance of cocoa plants against this pathogen, necrotic lesions, phenolic content and qualitative alteration of phenolics were conducted in ICS84 and ICS95 clones (two Trinitario introduced from …The cocoa black pod disease is caused by a fungus Phytophthora sp, which comprises two main species (Phytophthora palmivora and Phytophthora megakarya) commonly found in Ivorian cocoa plots and which cause significant damage. Despite numerous studies, this disease continues to spread and even more so Phytophthora …Phosphonic Acid: an Alternative Approach to the Control of Black Pod Disease of Cocoa Caused by Phytophthora Megakarya; Phytophthora Palmivora Establishes Tissue-Specific Intracellular Infection Structures in the Earliest Divergent Land Plant Lineage; Effect of Storage on the Antimicrobial Potencies of Some Botanicals Against Phytophthora ...Plants are prone to be attacked by various pathogenic microorganisms, leading to significant crop yield losses. Pesticides are used to control agricultural …Control of Phytophthora megakarya, the causal agent of cocoa black pod in Cameroon is commonly obtained by fungicide spraying of either copper compounds or a mixture of metalaxyl-M with copper ...Cocoa black pod rot, due to several Phytophthora spp., like Phytophthora megakarya, is the most important disease worldwide and the main cocoa disease in Africa, responsible for yield losses up to 50-80% in the absence of control measures. In thisPhytophthora megakarya is an oomycete plant pathogen that causes black pod disease in cocoa trees in west and central Africa. This pathogen can cause detrimental loss of yield in the economically important cocoa industry, worth approximately $70 billion annually. It can damage any part of the … See moreDownload scientific diagram | Spatial distribution of Phytophthora megakarya infections (2009-2016) in a cacao plantation in Kédia, established in 2006 from publication: Combining field ...Many Phytophthora species have a soil borne phase in their natural life cycles even though disease expression often occurs on aerial plant parts. In Cameroon, black pod rot of cacao (Theobroma cacao L.), is caused by P. megakarya. Primary inoculum ofsusceptibility leaf to Phytophthora megakarya. (Singh and Islam, 2010) proving th at the in vitro . culture of P. nicotianae and T. harzianum together . led to a variety of interactions. P. ...Studying spatial and temporal plant disease dynamics helps to understand pathogen dispersal processes, a necessary undertaking in epidemiology in order to improve disease control recommendations. In this study, plantations devoid of primary inoculumResearch on resistance to black pod caused by Phytophthora megakarya has been carried out in Cameroon for 40 years. It has yielded a significant database which is currently being exploited for the modelling of disease resistance levels of the major clones selected as candidate parents for the creation of new resistant and consequently more productive cocoa varieties.Phytophthora megakarya isolates were uniformly virulent in an assay using susceptible cacao pod husks inoculated with zoospores, while the P. palmivora isolates showed greater divergence in virulence. The virulence of P. megakarya was associated with earlier production of sporangia and an accelerated induction of necrosis. While zoos-Root inoculation of six Phytophthora parasitica isolates on Rpi-amr3 transgenic 224 Nicotiana benthamiana lines. 225 Representative photos for the P. parasitica root inoculation tests are shown ...Cocoa black pod rot, due to several Phytophthora spp., like Phytophthora megakarya, is the most important disease worldwide and the main cocoa disease in Africa, responsible for yield losses up to ...Objective: The in vitro and in vivo effects of seed extracts of Thevetia peruviana (Apocynaceae) on the growth and the germination of spores of Phytophthora megakarya causal agent of black pod of cocoa was evaluated. Methodology and results: Five extracts obtained by soxhlet apparatus (extracts of hexane, ethyl acetate, acetone, methanol and aqueous extract) were used.Although several Phytophthora species can infect cacao plants, only a few are considered important because of the extensive damage that they cause. In cacao plants, black pod is caused by four species of the genus Phytophthora: P. palmivora, P. megakarya, P. citrophthora and P. capsici/P. tropicalis .oomycete named Phytophthora megakarya known as the very aggressive between the Phytophthora species can reduce the production by 80 or 100% of the total production if n measure is taken. Many ...Phytophthora on cocoa pods. Adebola and Amadi (2011, 2012) reported using the fungi Aspergillus sp., Paecilomyces sp. and Penicillium digitatum (Pers.) Sacc. isolated from rhizosphere soils, to control black pod in the field. megakarya These antagonists/agents provide beneficial protective effects by using different mechanisms of suppression andAlthough several Phytophthora species can infect cacao plants, only a few are considered important because of the extensive damage that they cause. In cacao plants, black pod is caused by four species of the genus Phytophthora: P. palmivora, P. megakarya, P. citrophthora and P. capsici/P. tropicalis .The black pod disease caused by Phytophthora megakarya is responsible for 80% of the cocoa production loss in Cameroon. To assess the resistance of cocoa plants against this pathogen, necrotic lesions, phenolic content and qualitative alteration of phenolics were conducted in ICS84 and ICS95 clones (two Trinitario introduced from Trinidad) and ...Enter words / phrases / DOI / ISBN / keywords / authors / etc. Search. Advanced searchAn aqueous leaf extract of Talinum triangulare was screened for the presence of bioactive molecules, using gas chromatography coupled with pulse and flame ionization detectors. It had high carotenoids; moderate benzoic acid derivatives, hydroxycinnamates and flavonoids; and low terpenes, alkaloids, phytosterols, allicins, glycosides, saponins, and lignans contents.Objective: The in vitro and in vivo effects of seed extracts of Thevetia peruviana (Apocynaceae) on the growth and the germination of spores of Phytophthora megakarya causal agent of black pod of cocoa was evaluated. Methodology and results: Five extracts obtained by soxhlet apparatus (extracts of hexane, ethyl acetate, acetone, methanol and aqueous extract) were used.Phytophthora megakarya, on the other hand, occurs only in Africa, but represents a major threat to cacao production, the countries of West Africa being the largest producers of cacao in the world ...Phytophthora megakarya was first designated as the species P. palmivora MF3 ( Griffin, 1977) or P. palmivora L type and was described in 1979 as causing a disease of cacao (Brasier and Griffin, 1979). P. palmivora was considered to be the only causal organism of black pod of cocoa. The US Nematode Collection Search site is now available here.. We thank you for your patience and apologize for the delays in making the site available again.Phytophthora spp. in Clade 4: portion of the seven-loci ML phylogeny featuring the type cultures of 212 described species (by T. Bourret).Notice the position of P. megakarya selected specimen CBS 238.83 = S&T BL 73.In most parts of the world where Theobroma cacao is grown, Phytophthora palmivora is the major concern for causing black pod rot (BPR).Phytophthora megakarya, on the other hand, occurs only in Africa, but represents a major threat to cacao production, the countries of West Africa being the largest producers of cacao in the world.Since cacao did not originate in Africa, P. megakarya obviously ...Aug 1, 2015 · Nana et al. (2015) estimated the MIC of clove EO on Phytophthora megakarya at 250 μL/L on solid medium. For P. parasitica, the highest anti-oomycete activity was highlighted for clove EO with ... Identification of Theobroma cacao genes differentially expressed during Phytophthora megakarya infection . × Close Log In. Log in with Facebook Log in with Google. or. Email. Password. Remember me on this computer. or reset password. Enter the email address you signed up with and we'll email you a reset link. Need an account? ...Phytophthora megakarya is the most aggressive and can cause between 60 and 100 % crop loss (Djiekpor et al. 1981; Dakwa 1988). In contrast, P. palmivora is less aggressive and can cause crop losses of 4·9-19 % (Blencowe and Wharton 1961; Dakwa 1984); this species is more aggressive than P. capsici (Lawrence et al. 1982).The arrival and subsequent dispersal of Phytophthora megakarya within young cacao plantations, previously free of black pod and containing cacao germplasm that is evaluated for its resistance to P. megakarya, is the subject of an ongoing study in• Premise of the study: Phytophthora megakarya is the agent of black pod disease of cacao and is the main pathogen of this crop in Africa. Population genetic studies are required to investigate how this pathogen emerged. To this end, we developed 12 novel polymorphic microsatellite markers for P. megakarya.Jul 1, 2020 · (A) Black pod rot symptoms by P. megakarya and P. palmivora. (B) Approximate geographical distribution of P. megakarya (yellow area) and P. palmivora (blue area). (C) Clock-calibrated phylogenetic tree with estimated times of divergence and WGD duplication events in P. palmivora and P. megakarya in million years ago, with numbers of families expanded and contracted across multiple Phytophtora ... The oomycete genus Phytophthora includes devastating plant pathogens that are found in almost all ecosystems. We sequenced the genomes of two quarantined Phytophthora species–P. fragariae and P. rubi.Comparing these Phytophthora species and related genera allowed reconstruction of the phylogenetic relationships within the …Phytophthora megakarya in nurseries. The results showed that heat-treated oyster shells powder at 1% (w/w) soil amendment significantly increased plant height, leaf number, leaf area, dry shoot and root weight more than chemical fungicide and control treatment after twelve weeks of growth. ThePhytophthora megakarya; cacao plant; plant defence; Trichoderma asperellum Introduction Theobroma cacao L., commonly known as cacao, is an important economic crop in numerous developing countries. Cameroon is the fifth largest world cacao producer and its production of merchantable cacao inPhytophthora megakarya (Pmeg) and P. palmivora (Ppal) are oomycete pathogens that cause black pod rot of cacao (Theobroma cacao), the most economically important disease on cacao globally.608 Productivity and cocoa/Phytophthora megakarya interaction Journal of Plant Pathology (2010), 92 (3), 607-617 Trinidad before being distributed widely to other coun-tries; Cameroon included (Eskes and Lanaud, 1997). Field observation of cocoa pod invasion by P. megakarya have revealed the existence of partial geneti- cally heritable tolerance (Despréaux et al., 1989).Phytophthora megakarya isolate used in this study was obtained from the microorganism bank of the Laboratory of Phytoprotection and Plant Valorization (LPPV) of the Biotechnology Centre of the University of Yaoundé 1, Cameroon. Zoospore suspensions of P. megakarya isolate PM5 were obtained as described previously .Feb 1, 2008 · In Cameroon, various species of Phytophthora exist but the most prevalent and aggressive one is Phytophthora megakarya (Nyassé, 1997). Losses can reach up to 100% of the cocoa production in smallholders’ plantations when no control measures are taken (Despréaux et al., 1988, Berry and Cilas, 1994). In Cameroon, management of black pod ... Nana et al. (2015) estimated the MIC of clove EO on Phytophthora megakarya at 250 μL/L on solid medium. For P. parasitica, the highest anti-oomycete activity was highlighted for clove EO with ...Phytophthora pod rot (Black pod disease)-Ghana: Phytophthora megakarya and Phytophthora palmivora; Anonom, Asukuo, Kokoo proye Authors : A. Y. Akrofi , E. Moses Authors Info & Affiliations Publication : PlantwisePlus Knowledge BankOn the other end, several genome assemblies had high repeat content, namely, P. megakarya, Phytophthora hibernalis, and Phytophthora pinifolia contained 32.94, 32.46, and 33.00%, respectively. Fig. 1. Analysis of 31 Phytophthora species shows an abundance of repetitive elements. Species are shown in phylogenetic clade order; clade designations ...Phytophthora megakarya causes the severest damage in the main cacao producing countries in West Africa, while P. palmivora causes significant losses globally. M. perniciosa is related to a sister ...Phytophthora megakarya: Black pod disease: Syzygium aromaticum and Zanthoxylum xanthoxyloides : Pythium spp. Root rot: Thymus spp. Mikania scandens : Fusarium solani: Root rot, soft rot of plant tissues: 18 egyptian plant species : Metasequoia glyptostroboides : Eucalyptus erythrocorysThe goal of this study was to identify genes significantly regulated in response to Phytophthora megakarya early disease progression in a resistant (SCA6) and a susceptible (NA32) cacao genotype and to better understand basal differences in gene expression between these genotypes. Both SCA6 and NA32 are agronomically important genotypes.Studying spatial and temporal plant disease dynamics helps us to understand pathogen dispersal processes and improve disease control recommendations. In this study, three cacao plots devoid of primary inoculum of Phytophthora megakarya (causal agent of cacao black pod rot disease) upon establishment in 2006 were monitored for presence of disease on a weekly basis from 2009 to 2016. Ripley’s ...Phytophthora species produce a protein that has a similar sequence to the NEP1 of Fusarium oxysporium. Multiple copies of NEP1 orthologues have been identified in a P. megakarya strain and in four other Phytophthora species (P. citrophthora, P. capsici, P. palmivora and P. sojae) (Bae et al., 2005).PDF | On Aug 14, 2015, Wakam Louise Nana and others published Antimicrobial Activity of Syzygium aromaticum and Zanthoxylum xanthoxyloides Essential Oils Against Phytophthora megakarya.htm | Find ...Sep 1, 2002 · Phytophthora megakarya and Phytophthora palmivora cause black pod rot of cacao. P. megakarya occurs in Africa while P. palmivora is distributed world-wide. P. palmivora has a higher temperature maximum (34 °C) than P. megakarya (30 °C). Factors contributing to temperature maxima in Phytophthora species have not been studied in detail. Phytophthora megakarya only occurs in countries in West and Central Africa [3], yet since West and Central Africa produce around 70% of all cocoa beans worldwide, its economic impact is considerable. In Cameroon, cocoa black pod rot is only due to P. megakarya and losses can reach up to 80-90% when plantations are poorly managed [4, 5].Phytophthora megakarya is the most aggressive and can cause between 60 and 100 % crop loss (Djiekpor et al. 1981; Dakwa 1988). In contrast, P. palmivora is less aggressive and can cause crop losses of 4·9-19 % (Blencowe and Wharton 1961; Dakwa 1984); this species is more aggressive than P. capsici (Lawrence et al. 1982).In Cameroon, Phytophthora megakarya is the causal agent of black pod rot of cacao (Theobroma cacao L). Primary inoculum of P. megakarya is located in the soil. With the onset of the rainy season, this primary inoculum is activated and through rain splash cacao pods become infected.Nyassé, S., Despréaux, D., Cilas, C., Validity of a leaf inoculation test to assess the resistance to Phytophthora megakarya in a cocoa (Theobroma cacao L.) diallel mating design, Euphytica 123 (2002) 395 - 399. CrossRef Google Scholar