Phytophthora megakarya. Background: Phytophthora megakarya is an invasive pathogen endem...

Phytophthora megakarya is an oomycete plant pathogen that cause

Phytophthora megakarya in local and introduced cocoa varieties in Cameroon. Tropical Science, 43: 96–102. Pokou N.D., N'Goran J.A.K., Kebe I., Eskes A ...Studying spatial and temporal plant disease dynamics helps us to understand pathogen dispersal processes and improve disease control recommendations. In this study, three …Phytophthora megakarya, a Causal Agent of Black Pod Rot in Africa 1 Introduction. Phytophthora megakarya (Brasier and Griffin 1979 ), one of several …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.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.Cacao black pod rot (BPR), caused by Phytophthora megakarya is the most important cacao disease in Cameroon. Biocontrol of this disease using an oil-based formulation of Trichoderma asperellum PR11 provided more consistent and long-lasting protection of cacao pods under laboratory and experimental plot conditions. The objective of this study was to test this formulation under farmer field ...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 BankPhytophthora 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 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 ...The study of oomycetes associated with crops is highly important due to the economic losses they might cause. In cacao, the genus Phytophthora has been extensively studied, but little is known about other genera and species of oomycetes associated with this plant. This study aimed to determine the oomycetes’ diversity present in Colombian …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 ...Theobroma cacao seedling growth and tolerance to Phytophthora megakarya (causal agent of black pod disease) by heat-treated oyster shell powder nursery soil amendmen, Am. J. Plant.PCR-based identification of cacao black pod causal agents and identification of biological factors possibly contributing to Phytophthora megakarya's field dominance in West AfricaBlack pod rot, caused by Phytophthora palmivora, is a devastating disease of Theobroma cacao L. (cacao) leading to huge losses for farmers and limiting chocolate industry supplies. To understand resistance responses of cacao leaves to P. palmivora, Stage 2 leaves of genotypes Imperial College Selection 1 (ICS1), Colección Castro …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. It is the predominant cause of pod rot in Brazil where it is less aggressive than Phytophthora palmivora. Phytophthora citrophthora also attacks cocoa in Brazil.The 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.For example, the species of Phytophthora fungus (Phytophthora palmivora, Phytophthora megakarya, and Phytophthora capsici) cause black rod/pod rot, which leads to a 20-30% loss in yield and 10% mortality of cacao (Bridgemohan and Mohammed, 2019).In order to protect cacao against Phytophthora megakarya , the most aggressive pathogen of this plant in Cameroon, a study was carried out on hybrid genotypes of the family F79SA of cacao ( Theobroma cacao L.) to investigate the effect of inoculation of the biofertilizers Gigaspora margarita and Acaulospora tuberculata on the phenolic …PCR-based identification of cacao black pod causal agents and identification of biological factors possibly contributing to Phytophthora megakarya's field dominance in West Africa2019年8月12日 ... Phytophthora megakarya Brasier & M.J. Griffin 1979. This oomycete is found in western Africa where it is an important and specialized ...(From Brasier and Griffin, 1979).P. megakarya is a member of Group II of Phytophthora, as defined by Stamps et al. (1990). It produces caducous papillate …Enhance cocoa seedling growth and resistance against Phytophthora megakarya with oyster shell powder soil amendment. Increase plant height, leaf number, ...Abstract. Indonesia is a cocoa producing country with production of 425 thousand tons per year. However, production continues to decline, among others, caused by Phytopthora megakarya cause of ...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.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 withBlack pod disease caused by Phytophthora megakarya is the most important fungal disease on cocoa in Ghana. The current recommended control method of combining sanitation practices with 6 - 8 ...Nov 17, 2021 · This datasheet on Phytophthora megakarya covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Prevention/Control, Further Information. Identity Preferred Scientific Name Phytophthora megakarya Brasier & M.J. Griffin Preferred Common Name black pod of cocoa Bioassay of Geniculosporium species for Phytophthora megakarya biological control on cacao pod husk piecesBlack pod rot, caused by Phytophthora megakarya, is the main cause of cocoa harvest losses in Cameroon. Field experiments were carried out over two successive years in two smallholders' plots of ...Phytophthora 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.While the S type is considered to be P. palmivora, the L type was redescribed as P. megakarya and found to be the predominant species causing black pod of cocoa in Nigeria and Cameroon (Brasier and Sansome, 1977). ... Morphological distinctions between Phytophthora capsici and P. tropicalis sp. nov. Mycologia 93:137-145. Ashby, S. F. 1920.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. In culture, P. megakarya lost viability after 3 days at 32 ...Feb 23, 2016 · 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 ... 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 ... The aim of this study was to assess the chemical composition and the antimicrobial activity of essential oils of dried fruits and buds of Zanthoxylum xanthoxyloides (Z. xanthoxyloides) and Syzygium aromaticum (S. aromaticum or clove), respectively, against Phytophthora megakarya (P. megakarya).Essential oils were extracted by hydrodistillation, and their composition was determined by gas ...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 ...There was a significant genetic correlation between pod rot rate in the field and leaf test data, so using this resistance test could shorten cocoa tree selection cycles. Cocoa pod rot, caused by different Phytophthora species, is rife in all production zones. Phytophthora spp. control is therefore a major challenge for world cocoa cultivation, and selection of resistant material is a priority ...PDF | On Jan 1, 2019, Simo Claude published Effect of Biofertilizers on the Phenolic Content in a Hybrid Family of Cacao After Leaf Infection with Phytophthora megakarya and Exogenous Application ...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.Download scientific diagram | Spatial distribution of Phytophthora megakarya infections (2009-2016) in a cacao plantation in Kédia, established in 2006 from publication: Combining field ...[Show full abstract] genotypes and their offsprings with Phytophthora megakarya was performed in the nursery for two seasons (dry and rainy). Percentage success for crosses made using hand ...Phytophthora pod rot disease commonly known as the Black pod disease caused by Phytophthora palmivora and P. megakarya is the most destructive cocoa disease worldwide accounting for over 30% pod yield loss through pod rot and 10% tree death .Christian Nembot, Patrice Takam Soh, Gerben Martijn Hoopen, Yves Dumont, Modeling the temporal evolution of cocoa black pod rot disease caused by Phytophthora megakarya, Mathematical Methods in the Applied Sciences, 10.1002/mma.5206, 41, 18, (8816-8843), (2018).Phytophthora parasitica is a soilborne pathogen with a wide range of host plants and represents most species in the genus Phytophthora. In this review, we present some recent progress of P. parasitica research by highlighting important features that make it emerge as a model species of oomycete pathogens. The emerged model pathogen will ... 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 ... Recently, a number of researchers have shown interest in finding out the potential of natural substances of plant origin in crop protection. A study was carried out in Yaounde (Cameroon) to test the antifungal activity of extracts of ThevetiaPhytophthora megakarya Dataset GBIF Backbone Taxonomy Rank SPECIES Classification kingdom Chromista phylum Oomycota class Peronosporea ...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 ...In P. megakarya we identified a unique combination of WGD and large-scale transposable element driven genome expansion, which places this genome in the upper range of Phytophthora genome sizes, as ...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 andPhytophthora megakarya isolate L 2 C 2 is highly virulent on cacao pods and causes typical black pod symptoms on all the clones studied. Lesion size 5 days after inoculation was larger in highly susceptible clones than in the less susceptible ones. Nevertheless, two exceptions were observed in our study. The clones SNK213 and SNK416, known in ...Phytophthora megakarya infection. In order to analyse gene expression in response to P. megakarya inoculations of resistant and susceptible cocoa clones, a time course was conducted from 2 to 96 hpi. To verify the success of infection in plant tissues, half-leaves were conserved in a room culture for 6 days and fungal progression on the cocoa ...2015年3月2日 ... 29 Citations · Phytophthora megakarya, a Causal Agent of Black Pod Rot in Africa · Evaluation of the Epidemiological Factors Responsible for the ...Phytophthora megakarya is an Oomycete which has a negative impact on Cameroon cocoa production. An assessment of the level of virulence of different isolates of P. megakarya in mono or coinfection ...Jan 1, 2015 · 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 order to protect cacao against Phytophthora megakarya , the most aggressive pathogen of this plant in Cameroon, a study was carried out on hybrid genotypes of the family F79SA of cacao ( Theobroma cacao L.) to investigate the effect of inoculation of the biofertilizers Gigaspora margarita and Acaulospora tuberculata on the phenolic compound content in hybrid genotypes after leaf infection ...Methods : The artificial inoculation test on leaf discs, was used in this study to assess the susceptibility of 52 clones of high-producing cocoa trees resistant in the field to black podcausing by P. megakarya. Results : Three groups of susceptibility to P. megakarya were demonstrated according to the reference controls. The first group is ...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 only in West and Central …. PCR-based identification of cacao black pod causal agents anABSTRACT Pathogens of the Straminipile genus P 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 ...The impact of soil treatments on black pod rot (caused by Phytophthora megakarya) of cacao in Cameroon Abstract. Phytophthora megakarya (Pmeg) and Phy The 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 …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 ... Microsatellite markers for population st...

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