Phytophthora megakarya
P. megakarya is primarily known for the damage it causes to the cacao pod, but it is known to subsist on roots (Gregory et al., 1984) and can cause dieback of seedlings (Bowers et al., 2001). Since all Phytophthora spp. causing black pod disease of cacao in Africa were classified as P. palmivora prior to 1979 (Brasier and Griffin, 1979), it is ...The data indicated that Phytophthora species i.e. P. palmivora and P. megakarya were a significant source of variation in the results of the resistance tests. Interaction of the parents and the crosses with the Phytophthora species was not significant, indicating that the cultivars and their crosses did not change their relative ranking across ...Au Cameroun, l'espèce Phytophthora megakarya est la seule responsable de cette maladie et les pertes peuvent atteindre 100% si aucune mesure de contrôle n'est prise. En général, on ...
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Black pod rot of cocoa caused by Phytophthora megakarya causes significant losses in Cameroon. Normally (chemical) control efforts only begin when the first diseased pods appear. In theory, preventive control, focusing on reducing primary inoculum orPhytophthora megakarya is a(n) research topic. Over the lifetime, 121 publication(s) have been published within this topic receiving 2295 citation(s). Popular works include Taxonomy of 'Phytophthora palmivora' on cocoa, Isolation and identification of mycoparasitic isolates of Trichoderma asperellum with potential for suppression of black pod disease of cacao in Cameroon and more.Microsatellite markers for population studies of Phytophthora megakarya (Pythiaceae), a cacao pathogen in AfricaDec 31, 2020 · Background: Phytophthora megakarya is an invasive pathogen endemic to Central and West Africa. This species causes the most devastating form of black pod disease. Despite the deleterious impacts of this disease on cocoa production, there is no information on the geographic distribution of P. megakarya. To implement management strategies of Phytophthora pod rot (black pod) diseases successfully, knowledge of the role of economic plants, and the diversity and distribution of Phytophthora species on these plants in the cacao ecosystem is essential. In this study, the spread of Phytophthora megakarya in the cocoa growing districts of Ghana was monitored through annual surveys from 1985 to 2012.those of unknown sources constituted 19.0%. Phytophthora megakarya was frequently isolated from all the three sources of canker infections, indicating P. megakarya readily causes stem canker on cocoa.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 ...Phytophthora Megakarya. Phytophthora megakarya and P. palmivora are oomycete pathogens that cause black pod rot of cacao (Theobroma cacao), the most economically important disease on cacao globally. While P. palmivora is a cosmopolitan pathogen, P. megakarya, which is more aggressive on cacao than P. palmivora, has been reported …Phytophthora megakarya(PHYTMG). Menu. Overview → · EPPO links. Overview. Code created in: 1996-10-29. Basic information. EPPO Code: PHYTMG; Preferred name: ...Sep 9, 2018 · 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 ... Effect of Thevetia peruviana seeds extract on in vitro growth of four strains of Phytophthora megakarya Author(s) Ambang, Z; Dooh, JPN; Essono, G; Bekolo, N; Chewachong, G; Asseng, CC Year. 2010 Is Peer Reviewed? 1 Journal. Plant Omics ISSN: 1836-0661 Publisher. SOUTHERN CROSS PUBL ...Influence du microclimat sur l'installation de Phytophthora megakarya dans une parcelle cacaoyere initialement exempte d'auto inoculum (PDF) Influence du microclimat sur l'installation de Phytophthora megakarya dans une parcelle cacaoyere initialement exempte d'auto inoculum | Gerben Hoopen - Academia.eduObjective: 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.The formulation was tested for inhibition of spore germination in Phytophthora megakarya and showed 100% inhibition at 10% w/v of formulation. In planta assay performed on two hybrids of cocoa ...Influence du microclimat sur l'installation de Phytophthora megakarya dans une parcelle cacaoyere initialement exempte d'auto inoculum (PDF) Influence du microclimat sur l'installation de Phytophthora megakarya dans une parcelle cacaoyere initialement exempte d'auto inoculum | Gerben Hoopen - Academia.eduThe effects of some selected arbuscular mycorrhizal (AM) fungi, Gigaspora margarita and Glomus mossae on the growth and the role of soluble amino acids of two contrasting cocoa cultivars (ICS84 tolerant and SNK10 sensitive) against black pod disease caused by Phytophthora megakarya were investigated. Root colonization by AM fungi is between 50 and 70% 18 weeks after planting.Sep 9, 2020 · This is important as correct identification of the pathogen is crucial, since Ppal can be controlled by crop sanitation alone, whereas Phytophthora megakarya (Table 1) cannot [9,163,164]. Through sexual reproduction or interspecific hybridization, Phytophthora could gain allelic diversity and achieve large sexual/clonal population sizes through ... 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 ...Jan 10, 2023 · 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 ... Background: Phytophthora megakarya is an invasive pathogen endemic to Central and West Africa. This species causes the most devastating form of black pod disease. Despite the deleterious impacts ...
Microorganisms' origins. P. megakarya (strain PM 5) used in this study was obtained from infected cacao pod (Yaounde-Cameroon) (Tchameni Citation 2014).The zoospore suspension was obtained according to the method used by Sameza et al. (Citation 2014).Zoospore concentration was adjusted to 10 6 · ml −1 using a hemocytometer for spore counts.. Four isolates of Trichoderma asperellum (PR10 ...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 three most important species of Phytophthora worldwide causing black pod disease of cacao are P. palmivora, P. megakarya, and P. capsici. Chemicals are effective in controlling this disease but more natural methods would be preferred. One alternative is to use natural plant extracts. Rosemary and lavender leaf extracts were found to be effective in reducing germination of P. capsici, P ...Phytophthora 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 ...
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 ...taken from infected pods on P. megakarya [18]. The objective of this work was to improve the tolerance of a hybrid family of Theobroma cacao against the attack of Phytophthora megakarya through the assessment of the phenolic compounds content of the hybrid genotypes of the hybrid family F79SA of T. cacao after leaf infection withPhytophthora megakarya, Thevetia peruviana, extract, biocontrol, black pod disease. INTRODUCTION . The protection of plants against crop diseases and . pests is a key factor in the increase of cr op .…
Reader Q&A - also see RECOMMENDED ARTICLES & FAQs. Historical background. Phytophthora is arguably the . Possible cause: The effects of some selected arbuscular mycorrhizal (AM) fungi, Gigaspora margarita and Gl.
Phytophthora palmivora occurs in the center of origin of cocoa and causes 44 percent global crop loss. Phytophthora megakarya is restricted to Cameroon, Nigeria, Togo, and Ghana, causing about 10 percent crop loss. Phytophthora capsici parasitizes cocoa in Central and South America.The genus Phytophthora has been studied at the cellular level, suggesting that different developmental steps are induced by the expression of some specific genes. However, these studies have only been carried out on certain species, such as Phytophthora infestans and Phytophthora cactorum. ... Phytophthora megasperma and Phytophthora megakarya ...Phytophthora megakarya Brasier & Griffin, is one of the Oomycete pathogens reported on Theobroma cacao, and it is the most virulent of the Phytophthora species that causes black pod disease.Phytophthora megakarya was first reported as the causal agent of black pod disease in 1979 after the reclassification of Phytophthora species recovered from infected cacao tissues.
Phytophthora megakarya Brassier & Griffi n, the causal agent of black pod disease, is now the most important cacao pathogen in Central and West Africa . Losses are reported to be as high as 80% of potential yield in Cameroon, and can reach 100% in Ghana. Although cacao was introduced in Africa from South America, P. megakarya is a diploid ...Phytophthora megakarya Brasier & Griffin, is one of the Oomycete pathogens reported on Theobroma cacao,and it is the most virulent of the Phytophthora species that causes black pod disease. Phytophthora megakarya was first reported as the causal agent of black pod disease in 1979 after the reclassification of Phytophthora species recovered from ...
On the other end, several genome assemblies had high repeat Among the Phytophthora species that cause black pod of cacao, P. megakarya is the most virulent, posing a serious threat to cacao production in Africa. Correct identification of the species causing the black pod and understanding the virulence factors involved are important for developing sustainable disease management strategies. The aim of this study was to assess the chemical composition and the Phytophthora megakarya and P. palmivora are oomyce Download scientific diagram | Daily radial growth of Phytophthora megakarya from the Central strain in the presence of ethanolic extract. Values of the same parameter with different letters are ...On-farm farmer managed trials to control black pod disease caused by Phytophthora megakarya in Ghana. Proceedings of the First International Cocoa Pests and Disease Seminar [Internet]. 1995 :pp. 109-118. ... Phytophthora quercetorum sp. nov., a novel species isolated from eastern and north-central USA oak forest soils. Mycological Research ... Phytophthora megakarya Brasier & Griffin, is one of the O 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 ... The study by Zhu et al. reports that the Phytophthora sojae effec2017. Phytophthora megakarya and Phytophthora palmivora, closelPhytophthora Megakarya. Phytophthora megakarya and P. palmivor Phytophthora megakarya Brasier & Griffin, is one of the Oomycete pathogens reported on Theobroma cacao , and it is the most virulent of the Phytophthora species that causes black pod disease. Phytophthora megakarya was first reported as the causal agent of black pod disease in 1979 after the reclassification of Phytophthora species recovered from infected cacao tissues. The pathogen causes pod ...caused by Phytophthora megakarya and. Phytophthora palmivora on cocoa, Eur. J. Plant Pathol. 110 (2004) 983–990. [22] Jackson G.V.H., Sources of Phytophthora. palmivora inoculum in Solomon ... Research on resistance to black pod caused by Phytoph 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? ...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. From there repeated cycles of pod infection, … The oomycete genus Phytophthora includes devastating plant pathogens[inoculum of Phytophthora megakarya (causal agent Feb 15, 2016 · A phylogenetic tree generated for Phytophthora (Fy-TOFF-thor-uh) species make up a group of microorganisms that are important plant pathogens. The name Phytophthora derives from Greek and literally means “plant destroyer.” Phytophthora species resemble fungi but are not. While they are most closely related to aquatic organisms, such as brown algae and diatoms, they can also exist on land. However, Phytophthora organisms ...Aug 26, 2021 · Phytophthora megakarya is the most destructive fungal pathogen on cocoa production in Ghana . The disease has been in Ghana for many years but on other alternative hosts [ 16 ]. It was originally identified in Nigeria in 1979 [ 17 ], reported in Togo in 1982 [ 18 ], and was subsequently reported in Ghana in 1985 [ 16 ].