Phytophthora megakarya.

Phytophthora palmivora Phytophthora megakarya: Hosts: cocoa (Theobroma cacao) EPPO Code: PHYTPL: Black pod disease is a protozoal disease of Cocoa trees. This pathogen if left untreated can destroy all yields; annually the pathogen can cause a yield loss of up to 1/3 and up to 10% of total trees can be lost completely.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 ...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 ...Phytophthora megakarya is a devastating oomycete pathogen that causes black pod disease in cacao. Phytophthora species produce a protein that has a similar sequence to the necrosis and ethylene inducing protein (Nep1) of Fusarium oxysporum.Multiple copies of NEP1 orthologs (PmegNEP) have been identified in P. megakarya and four other Phytophthora species (P. citrophthora, P. capsici, P ...ABSTRACT Pathogens of the Straminipile genus Phytophthora cause significant disease losses to global cocoa production. P. megakarya causes significant pod rot and losses due to canker in West Africa, whereas P. capsici and P. citrophthora cause pod rots in Central and South America. The global and highly damaging P. palmivora …

Phytophthora là một chi Oomycetes gây hại cho cây, các loài trong chi này có thể gây hại kinh tế lớn đối với các vụ mùa trên toàn thế giới cũng như gây tổn môi trường hệ sinh …General information about Phytophthora megakarya (PHYTMG) on EPPO Q-Bank DatabaseIn African cacao-producing countries, control of cacao black pod disease caused by Phytophthora megakarya is a priority. Introducing biological control agents as part of a P. megakarya control strategy is highly desirable, especially in a perspective of pesticide reduction.Trichoderma species are among the most used biological control agents. In Cameroon, Trichoderma asperellum formulated in ...

Research 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. A new distribution map is provided for Phytophthora megakarya Brasier & M.J. Griffin. Hosts: Cocoa (Theobroma cacao). Information is given on the geographical distribution in Cameroon, Equatorial Guinea, Gabon, Ghana, Guinea, Nigeria, Togo.

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 …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 …Molecular and morphological identification of Phytophthora species based on the types and other well-authenticated specimens. IDphy was developed to facilitate accurate and efficient identification of Phytophthora to species, using type specimens from the original descriptions for reference wherever possible.IDphy emphasizes species of high economic impact and species of regulatory concern for ...The aims of this study were to investigate the chemical composition, in-vitro antioxidant and antibacterial activities of Syzygium aromaticum essential oil. The essential oil was obtained by hydrodistillation. The GC-MS/GC-FID was used for determination of essential oil composition. The antioxidant activity was determined by DPPH radical scavenging assay and reducing power. The ...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.

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 ...

Kajian Kitosan Sebagai Agens Pengendali Penyakit Busuk Buah Kakao (Phytophthora megakarya L.) ...

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.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, sporulation, spore ...P. megakarya is heterothallic with amphigynous antheridia and distinctly pyriform oogonia. The caducous sporangia are papillate, varying in shape from limoniform, obpyriform, and …Phytophthora palmivora (Butler) is an hemibiotrophic oomycete capable of infecting over 200 plant species including one of the most economically important crops, Theobroma cacao L. commonly known as cocoa. It infects many parts of the cocoa plant including the pods, causing black pod rot disease. This review will focus on P. palmivora's ability to infect a plant host to cause disease.Jan 31, 2007 · 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 ... 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). Phytophthora megakarya is a more aggressive pathogen than P. palmivora (Akrofi et al. 2003; Opoku et al. 2000). For example, P. palmivora was the only recognised causative agent of the black pod disease of cocoa in Ghana before 1985, resulting in 30% crop loss (Akrofi et al. 2003).

54 the black pod disease caused by Phytophthora spp. Two of the several species of the black pod 55 pathogen namely P. palmivora and P. megakarya have been identified as the causal agent of the 56 disease in Nigeria. P. palmivora (less than 20% distribution) and P. megakarya (over 80% 57 distribution) occur on cacao in Nigeria (3, 6 …Phytophthora megakarya is restricted to countries of West and Central Africa and considered to be a significant pathogen only on cacao. Black pod was originally reported to be caused by P. palmivora , but further findings have proven otherwise in that each continent has a complex of Phytophthora species, which induce black pod disease on cacao.Diseases are a major production constraint wherever cocoa (Theobroma cacao) is grown. The principal method of ameliorating cocoa production is the use of hybrid clones, which have resistance to important diseases and high productivity. To select new genotypes with resistance to Phytophtora megakarya, the cause of the destructive black pod disease, …Enter the email address you signed up with and we'll email you a reset link.Phytophthora megakarya (Pmeg) and Phytophthora palmivora (Ppal) are closely related species causing cacao black pod rot. Although Ppal is a cosmopolitan pathogen, cacao is the only known host of ...

Abstract. 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 Africa where it has been spreading and devastating ...

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 ...The impact of soil treatments on black pod rot (caused by Phytophthora megakarya) of cacao in CameroonPhytophthora megakarya is the most aggressive of the Phytophthora spp. attacking cocoa and poses a major threat to cocoa production in West and Central Africa (Akrofi et al. 2015). In Cameroon ..."Evaluation 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, Southwes," International Journal of Sciences, Office ijSciences, vol. 9(05), pages 1-8, May.Feb 14, 2017 · Plant materials. To identify the cacao responses to Pmeg and Ppal infection, various plant inoculation studies were carried out. For all the pod husk and leaf disc inoculation assays, Catongo cacao trees susceptible to Phytophthora; Crouzillat et al., 2000) were maintained in a USDA-ARS, Beltsville, MD greenhouse at 60% relative humidity and a photoperiod of 12 h light at 25 ± 3°C and 12 h ... 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 ...

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 ...

Dec 11, 2015 · Phytophthora megakarya was more aggressive than P. palmivora on attached SCA-6 pods, causing expanding necrotic lesions with or without wounding. Phytophthora megakarya is predominant in the Volta region of Ghana and it remains to be seen whether it can displace P. palmivora from cacao plantations of Ghana as it has in Nigeria and Cameroon.

All of the pathogens are found in the genus Phytophthora (a plant-damaging Oomycetes). The seven species responsible for black pod disease are; P. capsici, P. citrophthora, P. megasperma, P. katsurae, P. palmivora, and P. megakarya. While all of these pathogens can cause black pod disease the two major pathogens are P. palmivora and P. …Phytophthora palmivora (Butler) is an hemibiotrophic oomycete capable of infecting over 200 plant species including one of the most economically important crops, …Aug 1, 2022 · Flavonoids are phenolic compounds involved in defense mechanisms against black pod disease (BPD). Crossing between Forastero and Trinitario-resistant cocoa genotypes usually produce resistant progenies with high contents of bioactive components. This study aims at analyzing flavan-3-ol and flavonol content in the defense against P. megakarya in T. cacao genotypes for their potential selection ... 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 ...Phytophthora, causes substantial yield losses worldwide, particularly in Africa with the species Phytophthora megakarya, which is the most damaging species for the cocoa industry. Although P. megakarya only exists in Africa, the species Phytophthora palmivora and Phy-tophthora capsici are responsible for the disease in South America.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.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).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 …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).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 ...The only economically important host of Phytophthora megakarya Brasier & Griffin is Theobroma cacao. The pathogen is one of several Phytophthora species causing black pod disease of cacao. Isolates of P. megakarya were grouped taxonomically with P. palmivora isolates until 1979, when it was recognized as a new species (Brasier and Griffin, 1979).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

Diseases are a major production constraint wherever cocoa (Theobroma cacao) is grown. The principal method of ameliorating cocoa production is the use of hybrid clones, which have resistance to important diseases and high productivity. To select new genotypes with resistance to Phytophtora megakarya, the cause of the destructive black pod disease, comparative analyses (quantitative and ...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 ...Request PDF | On Oct 1, 2015, T. Legavre and others published Identification of Theobroma cacao genes differentially expressed during Phytophthora megakarya infection | Find, read and cite all the ...Instagram:https://instagram. s650 vs camarocraigslist estate sales wichita kskansas online collegeswsu mbb The study by Zhu et al. reports that the Phytophthora sojae effector PsAvh413 increases the enzyme activity of soybean trehalose 6-phosphate synthase (GmTPS), which … ku vs oklahoma basketball livetexas tech baseball big 12 tournament Download scientific diagram | Spatial distribution of Phytophthora megakarya infections (2009-2016) in a cacao plantation in Kédia, established in 2006 from publication: Combining field ...1. Introduction. Black pod disease, caused by Phytophthora megakarya, is one of the major diseases of cocoa that small-scale farmers are facing in West and Central Africa. In Cameroon, severe economic losses in cocoa production, which ranged from 30% to 80% were caused by this disease in all cocoa-growing regions where no proper control measures were applied [1], [2], [3]. web of sciece Phytophthora species are highly destructive plant pathogens and pose a significant threat to plants in various ecosystems, including agriculture, forest plantations, …Identification of Theobroma cacao genes differentially expressed during Phytophthora megakarya infectionIn 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 ...