Witches' broom disease (WBD) affects cocoa trees ( L.) and is caused by the fungus that grows in the apoplast in its biotrophic phase and later progresses into the tissues, causing serious losses in the production of cocoa beans. Therefore, the apoplast of can provide important defense responses during the interaction with .
View Article and Find Full Text PDFThe apoplast performs important functions in the plant, such as defense against stress, and compounds present form the apoplastic washing fluid (AWF). The fungus , the causal agent of witches' broom disease (WBD) in , initially colonizes the apoplast in its biotrophic phase. In this period, the fungus can remain for approximately 60 days, until it changes to its second phase, causing tissue death and consequently large loss in the production of beans.
View Article and Find Full Text PDFThe fungus secretes protein effectors that manipulate the physiology of the host plant, but few effectors of this fungus have had their functions confirmed. We performed functional characterization of a promising candidate effector of . The inoculation of rBASIDIN at 4 µmol L in the mesophyll of leaflets of caused symptoms of shriveling within 6 h without the presence of necrosis.
View Article and Find Full Text PDFThe viability of inoculum was evaluated during the microfermentation process of diseased and healthy pulp-seed masses and on a range of carrier materials: aluminum, cloth, glass, paper, plastic, raffia, and rubber tire. Fungal survival was assessed before the microfermentation (0 h) and every 24 to 96 h by the growth of colonies in potato-dextrose-agar (PDA) and sporulation in seed shells. Colonies of and sporulation on seed shells were observed from seeds not submitted to microfermentation.
View Article and Find Full Text PDFFront Microbiol
February 2023
Introduction: , the cocoa tree, is a target for pathogens, such as fungi from the genera , , , , among others. Some cacao pathogens are restricted to specific regions of the world, such as the (CSSV) in West African countries, while others are expanding geographically, such as in the Americas. is one of the most threatening cacao pathogens since it directly attacks the cacao pods driving a significant reduction in production, and therefore economic losses.
View Article and Find Full Text PDFCacao is a globally important crop with a long history of domestication and selective breeding. Despite the increased use of elite clones by cacao farmers, worldwide plantations are established mainly using hybrid progeny material derived from heterozygous parents, therefore displaying high tree-to-tree variability. The deliberate development of hybrids from advanced inbred lines produced by successive generations of self-pollination has not yet been fully considered in cacao breeding.
View Article and Find Full Text PDFProtease inhibitors (PIs) are important biotechnological tools of interest in agriculture. Usually they are the first proteins to be activated in plant-induced resistance against pathogens. Therefore, the aim of this study was to characterize a Theobroma cacao trypsin inhibitor called TcTI.
View Article and Find Full Text PDFMoniliophthora perniciosa is a basidiomycete responsible for the witches' broom disease in cacao (Theobroma cacao L.). Chitin synthase (CHS), chitinase (CHIT) and autophagy (ATG) genes have been associated to stress response preceding the formation of basidiocarp.
View Article and Find Full Text PDFBackground: Witches' broom disease (WBD) of cacao (Theobroma cacao L.), caused by Moniliophthora perniciosa, is the most important limiting factor for the cacao production in Brazil. Hence, the development of cacao genotypes with durable resistance is the key challenge for control the disease.
View Article and Find Full Text PDFThe surface of plants forms a defense barrier that directly inhibits the first point of contact of microorganisms with the host. To understand this defense mechanism in Moniliophthora perniciosa interaction with Theobroma cacao cv Catongo, the aim of this study was to compare the changes in protein expression in basidiospores of the fungus M. perniciosa in response the leaf water washes (LWW) of two contrasting cocoa varieties for resistance to witches' broom disease.
View Article and Find Full Text PDFBMC Microbiol
November 2018
Background: Theobroma cacao L. (cacao) is a perennial tropical tree, endemic to rainforests of the Amazon Basin. Large populations of bacteria live on leaf surfaces and these phylloplane microorganisms can have important effects on plant health.
View Article and Find Full Text PDFBackground: The hemibiotrophic pathogens Moniliophthora perniciosa (witches' broom disease) and Moniliophthora roreri (frosty pod rot disease) are among the most important pathogens of cacao. Moniliophthora perniciosa has a broad host range and infects a variety of meristematic tissues in cacao plants, whereas M. roreri infects only pods of Theobroma and Herrania genera.
View Article and Find Full Text PDFBackground: Moniliophthora perniciosa is a phytopathogenic fungus responsible for witches' broom disease of cacao trees (Theobroma cacao L.). Understanding the molecular events during germination of the pathogen may enable the development of strategies for disease control in these economically important plants.
View Article and Find Full Text PDFPLoS One
August 2017
The genus Theobroma comprises several trees species native to the Amazon. Theobroma cacao L. plays a key economic role mainly in the chocolate industry.
View Article and Find Full Text PDFLegumains are cysteine proteases related to plant development, protein degradation, programmed cell death, and defense against pathogens. In this study, we have identified and characterized three legumains encoded by Theobroma cacao genome through in silico analyses, three-dimensional modeling, genetic expression pattern in different tissues and as a response to the inoculation of Moniliophthora perniciosa fungus. The three proteins were named TcLEG3, TcLEG6, and TcLEG9.
View Article and Find Full Text PDFThe interaction amongst papain-like cysteine-proteases (PLCP) and their substrates and inhibitors, such as cystatins, can be perceived as part of the molecular battlefield in plant-pathogen interaction. In cacao, four cystatins were identified and characterized by our group. We identified 448 proteases in cacao genome, whereof 134 were cysteine-proteases.
View Article and Find Full Text PDFGenet Mol Biol
October 2014
The phytopathogenic fungus Moniliophthora perniciosa (Stahel) Aime & Philips-Mora, causal agent of witches' broom disease of cocoa, causes countless damage to cocoa production in Brazil. Molecular studies have attempted to identify genes that play important roles in fungal survival and virulence. In this study, sequences deposited in the M.
View Article and Find Full Text PDFPlant Physiol Biochem
December 2013
The level of hydrogen peroxide (H2O2) in plants signalizes the induction of several genes, including that of ascorbate peroxidase (APX-EC 1.11.1.
View Article and Find Full Text PDFClonal genotypes resistant to fungal diseases are an important component of the cocoa production system in southeastern Bahia state (Brazil), so that technologies for faster production of stronger and healthier plantlets are highly desirable. In this study, the effects of inoculated bacterial endophytes isolated from healthy adult cacao plants on seedlings, and aspects related to inoculation methods, colonization patterns, and photosynthesis were investigated. Sequencing of 16S rRNA, hsp-60, and rpo-B genes placed the wild-type isolates within the species Enterobacter cloacae (isolates 341 and 344) and Bacillus subtilis (isolate 629).
View Article and Find Full Text PDFMicrobiology (Reading)
January 2013
Boto, a class II transposable element, was characterized in the Moniliophthora perniciosa genome. The Boto transposase is highly similar to plant PIF-like transposases that belong to the newest class II superfamily known as PIF/Harbinger. Although Boto shares characteristics with PIF-like elements, other characteristics, such as the transposase intron position, the position and direction of the second ORF, and the footprint, indicate that Boto belongs to a novel family of the PIF/Harbinger superfamily.
View Article and Find Full Text PDFThis study reports on expression analysis associated with molecular systems biology of cacao-Moniliophthora perniciosa interaction. Gene expression data were obtained for two cacao genotypes (TSH1188, resistant; Catongo, susceptible) challenged or not with the fungus M. perniciosa and collected at three time points through disease.
View Article and Find Full Text PDFTheobroma cacao is an economically important tree of several tropical countries. Its genetic improvement is essential to provide protection against major diseases and improve chocolate quality. We discovered and mapped new expressed sequence tag-single nucleotide polymorphism (EST-SNP) and simple sequence repeat (SSR) markers and constructed a high-density genetic map.
View Article and Find Full Text PDFIn plant-pathogen interaction, the hydrogen peroxide (H₂O₂) may play a dual role: its accumulation inhibits the growth of biotrophic pathogens, while it could help the infection/colonization process of plant by necrotrophic pathogens. One of the possible pathways of H₂O production involves oxalic acid (Oxa) degradation by apoplastic oxalate oxidase. Here, we analyzed the production of H₂O₂, the presence of calcium oxalate (CaOx) crystals and the content of Oxa and ascorbic acid (Asa)--the main precursor of Oxa in plants--in susceptible and resistant cacao (Theobroma cacao L.
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