scholarly journals Structural and Functional Genomics of the Resistance of Cacao to Phytophthora palmivora

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 961
Author(s):  
Jonathan Javier Mucherino Muñoz ◽  
Cláusio Antônio Ferreira de Melo ◽  
Raner José Santana Silva ◽  
Edna Dora Martins Newman Luz ◽  
Ronan Xavier Corrêa
Keyword(s):  
Kinase Domain ◽  
Coiled Coils ◽  
Chromosome 8 ◽  
Phytophthora Palmivora ◽  
Chromosome 2 ◽  
Nucleotide Binding Sites ◽  
Phytophthora Spp ◽  
Ssr Loci ◽  
Black Pod ◽  
Genomic Regions

Black pod disease, caused by Phytophthora spp., is one of the main diseases that attack cocoa plantations. This study validated, by association mapping, 29 SSR molecular markers flanking to QTL (Quantitative Trait Loci) associated with Phytophthora palmivora Butler (Butler) (PP) resistance, in three local ancient varieties of the Bahia (Comum, Pará, and Maranhão), varieties that have a high potential in the production of gourmet chocolate. Four SSR loci associated with resistance to PP were detected, two on chromosome 8, explaining 7.43% and 3.72% of the Phenotypic Variation (%PV), one on chromosome 2 explaining 2.71%PV and one on chromosome 3 explaining 1.93%PV. A functional domains-based annotation was carried out, in two Theobroma cacao (CRIOLLO and MATINA) reference genomes, of 20 QTL regions associated with cocoa resistance to the pathogen. It was identified 164 (genome CRIOLLO) and 160 (genome MATINA) candidate genes, hypothetically involved in the recognition and activation of responses in the interaction with the pathogen. Genomic regions rich in genes with Coiled-coils (CC), nucleotide binding sites (NBS) and Leucine-rich repeat (LRR) domains were identified on chromosomes 1, 3, 6, 8, and 10, likewise, regions rich in Receptor-like Kinase domain (RLK) and Ginkbilobin2 (GNK2) domains were identified in chromosomes 4 and 6.

scholarly journals Phytophthora palmivora Causing Disease on Theobroma cacao in Hawaii

Agriculture ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 396
Author(s):  
Alina Sandra Puig ◽  
Wilber Quintanilla ◽  
Tracie Matsumoto ◽  
Lisa Keith ◽  
Osman Ariel Gutierrez ◽  
...  
Keyword(s):  
Theobroma Cacao ◽  
Temperature Response ◽  
Molecular Data ◽  
Phytophthora Species ◽  
Phytophthora Palmivora ◽  
Growth Responses ◽  
Temperature Growth ◽  
Phytophthora Spp ◽  
Hawaii Island ◽  
Black Pod

Commercial production of cacao in Hawaii has doubled in the past 10 years, and farmers are receiving premium prices for their beans from the expanding local confectionery industry. Black pod, caused by Phytophthora spp., is the only major cacao disease that has been reported in Hawaii but distribution and molecular identification are lacking. To determine the species of Phytophthora affecting Theobroma cacao, a sampling trip was conducted on Hawaii Island and Oahu. Ten isolates of Phytophthora palmivora were obtained from diseased cacao on Hawaii Island, but none from Oahu, despite the presence of symptomatic pods. No other Phytophthora species were found. Laboratory studies showed that all isolates produced lesions on unwounded cacao pods, but they differed in terms of their temperature–growth responses. Fungicide sensitives for a subset of isolates (n = 4) were determined using media amended with a range of fungicide concentrations. The Hawaiian isolates of P. palmivora were more sensitive to mefenoxam, chlorothalonil, and fosetyl-Al, than isolates from Ghana (n = 2) and Mexico (n = 1). This study identifies P. palmivora as a causal agent of black pod in Hawaii based on molecular data and provides valuable preliminary information on fungicide resistance and temperature response that can be used to improve disease management.

scholarly journals QTL mapping and identification of corresponding genomic regions for black pod disease resistance to threePhytophthoraspecies inTheobroma cacaoL

2018 ◽  
Author(s):  
MA Barreto ◽  
JRBF Rosa ◽  
ISA Holanda ◽  
CB Cardoso-Silva ◽  
CIA Vildoso ◽  
...  
Keyword(s):  
Genetic Map ◽  
Resistance Genes ◽  
Mixed Model ◽  
Phytophthora Capsici ◽  
Raw Material ◽  
Phytophthora Palmivora ◽  
Joint Analysis ◽  
Black Pod ◽  
Black Pod Disease ◽  
Genomic Regions

AbstractThe cacao tree (Theobroma cacaoL.) is a species of great importance because cacao beans are the raw material used in the production of chocolate. However, the economic success of cacao is largely limited by important diseases such as black pod, which is responsible for losses of up to 30-40% of the global cacao harvest. The discovery of resistance genes could extensively reduce these losses. Therefore, the aims of this study were to construct an integrated multipoint genetic map, align polymorphisms against the available cacao genome, and identify quantitative trait loci (QTLs) associated with resistance to black pod disease in cacao. The genetic map had a total length of 956.41 cM and included 186 simple sequence repeat (SSR) markers distributed among 10 linkage groups. The physical “in silico” map covered more than 200 Mb of the cacao genome. Based on the mixed model predicted means ofPhytophthoraevaluation, a total of 6 QTLs were detected forPhytophthora palmivora(1 QTL),Phytophthora citrophthora(1 QTL), andPhytophthora capsici(4 QTLs). Approximately 1.77% to 3.29% of the phenotypic variation could be explained by the mapped QTLs. Several SSR marker-flanking regions containing mapped QTLs were located in proximity to disease regions. The greatest number of resistance genes was detected in linkage group 6, which provides strong evidence for a QTL. This joint analysis involving multipoint and mixed-model approaches may provide a potentially promising technique for detecting genes resistant to black pod and could be very useful for future studies in cacao breeding.

Genetic diversity of native cultivated cacao accessions (Theobroma cacao L.) in Nicaragua

2012 ◽  
Vol 10 (3) ◽  
pp. 254-257
Author(s):  
Erwin Aragon ◽  
Claudia Rivera ◽  
Helena Korpelainen ◽  
Aldo Rojas ◽  
Paula Elomaa ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Theobroma Cacao ◽  
Phytophthora Palmivora ◽  
Genetic Composition ◽  
Breeding Programmes ◽  
Black Pod ◽  
Black Pod Disease ◽  
Parental Lines ◽  
Resistant Genotypes ◽  
Theobroma Cacao L

A total of 60 farmers' cacao accessions (Theobroma cacao L.) from Nicaragua were investigated using microsatellite markers to reveal their genetic composition and to identify potentially resistant genotypes against the black pod disease caused by Phytophthora palmivora. These accessions were compared with 21 breeders' accessions maintained locally, two Criollo accessions from Costa Rica and two accessions from Ecuador. The analyses showed a low level of differentiation among groups of farmers' accessions (FST = 0.06) and that six Nicaraguan accessions were genetically closely related to the two Criollo accessions used as a reference. In addition, seven distinct genotypes were found to have allelic composition that may indicate linkage to resistance alleles, thus being potential parental lines in future breeding programmes.

scholarly journals The expression of pathogenicity-related genes in Phytophthora palmivora causing black pod rot disease on cacao (Theobroma cacao L.) in Indonesia

2021 ◽  
Vol 16 (1) ◽  
pp. 284-295
Author(s):  
Masanto Masanto ◽  
Arif Wibowo ◽  
Nur Fathurahman Ridwan ◽  
Widhi Dyah Sawitri ◽  
Koji Kageyama ◽  
...  
Keyword(s):  
Theobroma Cacao ◽  
Phytophthora Palmivora ◽  
Black Pod ◽  
Rot Disease ◽  
Theobroma Cacao L

scholarly journals Growth Inhibition of Cocoa Pod Rot Fungus Phytophthora palmivora byPseudomonas fluorescence and Bacillus subtilis bacteria

2013 ◽  
Vol 29 (2) ◽  
Author(s):  
Sakti Widyanta Pratama ◽  
Sri Sukamto ◽  
Lis Nur Asyiah ◽  
Yeni Vida Ervina
Keyword(s):  
Bacillus Subtilis ◽  
Fungal Growth ◽  
Petri Dish ◽  
Phytophthora Palmivora ◽  
Fungal Treatment ◽  
Pure Cultures ◽  
Black Pod ◽  
Black Pod Disease ◽  
First Time ◽  
Important Disease

Black pod disease caused by Phytophthora palmivorafungus is one of the important diseases on cocoa crop. Pod rot is the most important disease because it may cause loss of cocoa pod. Until now, the fungal pathogen of cocoa black pod disease is still a crucial problem and there is no fungicide that is really effective against the disease. One alternative to control the cocoa black pod disease is by using biological agents as biofungicide, including utilizing Pseudomonas fluorescenceand Bacillus subtilis bacteria. The research was done by isolation of P. palmivora from infected pods of Kaliwining Experimental Station to obtain pure cultures of fungus and by multiplication of P. fluorescence and B. subtilis. Antagonist test was performed by inoculating P. palmivora into a petri dish in a distance of 3 cm from the edge. P. fluorescenceand B. Subtilis were inoculated into petridishes in three days after the fungal treatment. Control was inoculated with isolate of P. palmivora only. Fungal growth was measured everyday by measuring radius of fungal colonies first time 24 hours after inoculation. Growth of Phytophthora palmivora in the two treatmens were used to calculate the percentage of inhibition. The results of this study indicated that P. fluorescence and B. subtiliswere able to inhibit fungal growth of P. palmivora. Both bacterial antagonists had the same effectiveness in inhibiting the growth of P. palmivora fungus based on the percentage of inhibition and effectiveness criteria. Based on the results of translucent zones indicated that B. subtiliswas more powerfull in inhibiting growth of P. Palmivora compared to P. fluorescence. Key words: Black pod disease of cocoa, biological control, Phytophthora palmivora, Pseudomonas fluorescence, Bacillus subtilis

scholarly journals LOCALIZATION IN THE TOMATO GENOME OF DNA RESTRICTION FRAGMENTS CONTAINING SEQUENCES HOMOLOGOUS TO THE rRNA (45S), THE MAJOR CHLOROPHYLL a/b BINDING POLYPEPTIDE AND THE RIBULOSE BISPHOSPHATE CARBOXYLASE GENES

Genetics ◽  
1986 ◽  
Vol 112 (1) ◽  
pp. 93-105
Author(s):  
C E Vallejos ◽  
S D Tanksley ◽  
R Bernatzky
Keyword(s):  
Chlorophyll A ◽  
Ribosomal Rna ◽  
Chromosome 8 ◽  
Ribulose Bisphosphate Carboxylase ◽  
Chromosome 2 ◽  
Ribulose Bisphosphate ◽  
Bisphosphate Carboxylase ◽  
Restriction Fragments ◽  
Dna Restriction Fragments ◽  
Dna Restriction

ABSTRACT DNA restriction fragments containing sequences homologous to the ribosomal RNA (45s), the major chlorophyll a/b binding polypeptide (CAB) and the small subunit of ribulose bisphosphate carboxylase (RBCS) genes have been localized and mapped in the tomato nuclear genome by linkage analysis. Ribosomal RNA genes map to a single locus, R45s, which resides in a terminal position on the short arm of chromosome 2 and corresponds to the Nucleolar Organizer Region. The size of the 45s repeating unit is estimated to be approximately 9 kb in Lycopersicon esculentum and 11 kb in Lycopersicon pennellii. Five loci were found to contain CAB sequences. Two of the loci, Cab-1 (chromosome 2) and Cab-3 (chromosome 8), together accounted for more than 80% of the hybridization signal. These loci contain more than one CAB structural gene. The other three loci, Cab-2 (chromosome 8), Cab-4 (chromosome 7) and Cab-5 (chromosome 12), each account for <10% of the total signal and may contain only a single copy of the CAB structural sequence. Three loci were found to contain RBCS sequences. Rbcs-2 (chromosome 3) and Rbcs-3 (chromosome 2) were responsible for >80% of the signal, with the remainder being associated with Rbcs-1 (chromosome 2). Rbcs-2 and Rbcs-3 may contain more than one copy of the gene.

Generation of a variant t(2;8) translocation of Burkitt's lymphoma by site-specific recombination via the kappa light-chain joining signals

1987 ◽  
Vol 7 (6) ◽  
pp. 2037-2045
Author(s):  
P Hartl ◽  
M Lipp
Keyword(s):  
Light Chain ◽  
Half Life ◽  
Early Stage ◽  
Burkitt’S Lymphoma ◽  
Chromosome 8 ◽  
Burkitt's Lymphoma ◽  
Kappa Light Chain ◽  
Chromosome 2 ◽  
B Cell Differentiation ◽  
Myc Gene

We analyzed the Burkitt's lymphoma line BL64 in which a reciprocal translocation joins the immunoglobulin kappa light-chain locus on chromosome 2 to the c-myc gene on chromosome 8. The breakpoints on the two marker chromosomes 8+ and 2p- occurred 5' of the Js segment within the conserved nonamer and heptamer recombination sequences. Both signals were detected directly adjacent to the breakpoints in sequences of chromosome 8 suggesting that the translocation in BL64 was catalyzed by enzymes normally involved in V-J recombination. The distance between the c-myc gene and the breakpoint in J kappa amounts to at least 90 kilobases on the DNA level. In one allele of the c-myc gene somatic mutations were found in the promoter-leader region. This allele is transcribed and is supposed to be involved in the translocation. The half-life of the c-myc-specific mRNA in BL64 cells is not prolonged in comparison to the normal c-myc message. These results suggest that in Burkitt's lymphoma the translocation occurs during an early stage of B-cell differentiation and that in the variant translocations mechanisms other than a prolonged half-life, such as changes in transcriptional rates, or other posttranscriptional RNA processing contribute to the high steady-state level of c-myc RNA in the cytoplasm.

scholarly journals Isolation, identification and characterization of endophytic bacteria antagonistic to Phytophthora palmivora causing black pod of cocoa in Malaysia

2019 ◽  
Vol 155 (4) ◽  
pp. 1077-1091 ◽  
Author(s):  
Wael Alsultan ◽  
Ganesan Vadamalai ◽  
Ahmad Khairulmazmi ◽  
Halimi Mohd Saud ◽  
Abdullah M. Al-Sadi ◽  
...  
Keyword(s):  
Endophytic Bacteria ◽  
Phytophthora Palmivora ◽  
Black Pod ◽  
Identification And Characterization

scholarly journals Identification of Neuronal Enhancers of the Proopiomelanocortin Gene by Transgenic Mouse Analysis and Phylogenetic Footprinting

2005 ◽  
Vol 25 (8) ◽  
pp. 3076-3086 ◽  
Author(s):  
Flávio S. J. de Souza ◽  
Andrea M. Santangelo ◽  
Viviana Bumaschny ◽  
María Elena Avale ◽  
James L. Smart ◽  
...  
Keyword(s):  
Energy Homeostasis ◽  
Significant Quantitative Trait Locus ◽  
Phylogenetic Footprinting ◽  
Transcriptional Unit ◽  
Human Populations ◽  
Chromosome 2 ◽  
Loss Of Function ◽  
Trait Locus ◽  
Genomic Regions ◽  
Arcuate Neurons

ABSTRACT The proopiomelanocortin (POMC) gene is expressed in the pituitary and arcuate neurons of the hypothalamus. POMC arcuate neurons play a central role in the control of energy homeostasis, and rare loss-of-function mutations in POMC cause obesity. Moreover, POMC is the prime candidate gene within a highly significant quantitative trait locus on chromosome 2 associated with obesity traits in several human populations. Here, we identify two phylogenetically conserved neuronal POMC enhancers designated nPE1 (600 bp) and nPE2 (150 bp) located approximately 10 to 12 kb upstream of mammalian POMC transcriptional units. We show that mouse or human genomic regions containing these enhancers are able to direct reporter gene expression to POMC hypothalamic neurons, but not the pituitary of transgenic mice. Conversely, deletion of nPE1 and nPE2 in the context of the entire transcriptional unit of POMC abolishes transgene expression in the hypothalamus without affecting pituitary expression. Our results indicate that the nPEs are necessary and sufficient for hypothalamic POMC expression and that POMC expression in the brain and pituitary is controlled by independent sets of enhancers. Our study advances the understanding of the molecular nature of hypothalamic POMC neurons and will be useful to determine whether polymorphisms in POMC regulatory regions play a role in the predisposition to obesity.

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