About: Jacaratia is a research topic. Over the lifetime, 11 publications have been published within this topic receiving 393 citations.
TL;DR: The authors investigated the evolution of the Caricaceae based on sequences from all species and genera, the monospecific Carica, African Cylicomorpha with two species, South American Jacaratia and Vasconcellea with together c. 28 species, and Mexican/Guatemalan Jarilla and Horovitzia with four species.
Abstract: Papaya (Carica papaya) is a crop of great economic importance, and the species was among the first plants to have its genome sequenced. However, there has never been a complete species-level phylogeny for the Caricaceae, and the crop’s closest relatives are therefore unknown. We investigated the evolution of the Caricaceae based on sequences from all species and genera, the monospecific Carica, African Cylicomorpha with two species, South American Jacaratia and Vasconcellea with together c. 28 species, and Mexican/Guatemalan Jarilla and Horovitzia with four species. Most Caricaceae are trees or shrubs; the species of Jarilla, however, are herbaceous. We generated a matrix of 4177 nuclear and plastid DNA characters and used maximum likelihood (ML) and Bayesian analysis to infer species relationships, rooting trees on the Moringaceae. Divergence times were estimated under relaxed and strict molecular clocks, using different subsets of the data. Ancestral area reconstruction relied on a ML approach. The deepest split in the Caricaceae occurred during the Late Eocene, when the ancestor of the Neotropical clade arrived from Africa. In South America, major diversification events coincide with the Miocene northern Andean uplift and the initial phase of the tectonic collision between South America and Panama resulting in the Panamanian land bridge. Carica papaya is sister to Jarilla/Horovitzia, and all three diverged from South American Caricaceae in the Oligocene, 27 (22–33) Ma ago, coincident with the early stages of the formation of the Panamanian Isthmus. The discovery that C. papaya is closest to a clade of herbaceous or thinstemmed species has implications for plant breeders who have so far tried to cross papaya only with woody highland papayas (Vasconcellea).
TL;DR: The specific clustering of the highly diverse group of Vasconcella × heilbornii accessions suggests that these genotypes may be the result of bi-directional introgression events between Vascon cella stipulata and Vascon Cella cundinamarcensis.
Abstract: The AFLP technique was used to assess the genetic relationships among the cultivated papaya (Carica papaya L) and related species native to Ecuador Genetic distances based on AFLP data were estimated for 95 accessions belonging to three genera including C papaya, at least eight Vasconcella species and two Jacaratia species Cluster analysis using different methods and principal co-ordinate analysis (PCO), based on the AFLP data from 496 polymorphic bands generated with five primer combinations, was performed The resulted grouping of accessions of each species corresponds largely with their taxonomic classifications and were found to be consistent with other studies based on RAPD, isozyme and cpDNA data The AFLP analysis supports the recent rehabilitation of the Vasconcella group as a genus; until recently Vasconcella was considered as a section within the genus Carica Both cluster and PCO analysis clearly separated the species of the three genera and illustrated the large genetic distance between C papaya accessions and the Vasconcella group The specific clustering of the highly diverse group of Vasconcella × heilbornii accessions also suggests that these genotypes may be the result of bi-directional introgression events between Vasconcella stipulata and Vasconcella cundinamarcensis
TL;DR: The chloroplast and mitochondrial DNA diversity of 61 genotypes belonging to 18 Vasconcellea species was studied by PCR-RFLP analysis, and intraspecific cpDNA variation was detected in V. × heilbornii, providing molecular evidence for the high diversity previously indicated by morphological observations.
Abstract: The chloroplast and mitochondrial DNA diversity of 61 genotypes belonging to 18 Vasconcellea species, the so-called highland papayas, was studied by PCR-RFLP analysis of two non-coding cpDNA regions (trnM-rbcL and trnK1-trnK2) and one non-coding mtDNA region (nad4/1-nad4/2). This sample set was supplemented with six genotypes belonging to three other Caricaceae genera: the monotypic genus Carica, including only the cultivated papaya, and the genera Jacaratia and Cylicomorpha. Moringa ovalifolia was added as an outgroup species. The PCR-amplified cpDNA regions were digested with 18 restriction endonucleases, the mtDNA region with 11. A total of 22 point mutations and four insertion/deletions were scored in the sample. A higher level of interspecific variation was detected in the two cpDNA regions in comparison to the analysis of the mtDNA. Wagner parsimony and Neighbor-Joining analysis resulted in dendrograms with similar topologies. PCR-RFLP analysis supported the monophyly of Caricaceae, but among the 26 mutations scored, an insufficient number of markers discriminated between the different Caricaceae genera included in this study. Hence the inference of the intergeneric relationships within Caricaceae was impossible. However, some conclusions can be noted at a lower taxonomic level. The Caricaceae species were divided into two lineages. One group included only Vasconcellea spp., whereas the second included the remaining Vasconcellea spp., together with the papaya genotypes and those from the other Caricaceae genera. This may indicate a higher level of inter-fertility for the Vasconcellea species from the latter clade in interspecific crossings with papaya. The putative progenitors of the natural sterile hybrid V. × heilbornii, i.e. V. stipulata and V. cundinamarcensis, were only distantly related to V. × heilbornii. This indicates that probably none of these species was involved as the maternal progenitor in the origin of V. × heilbornii. Surprisingly, V. × heilbornii had organellar genome patterns identical with V. weberbaueri, suggesting a possible involvement of this species in the origin of V. × heilbornii. On the basis of discrepancy between morphological traits and the cpDNA profiles of some pairs of Vasconcellea species, we believe that besides V. × heilbornii, some other species have originated through interspecific hybridization. A reticulate evolution for Vasconcellea has therefore been suggested. Finally, intraspecific cpDNA variation was detected in V. microcarpa, thus providing molecular evidence for the high diversity previously indicated by morphological observations.
TL;DR: The striking quantitative differences suggest the possible use of BITC content as a chemotaxonomic criterion in seeds of Jacaratia.
Abstract: GLC quantitation of benzyl isothiocyanate (BITC) in 1–2 macerated seeds of Caricaceae is described. In Carica and Jarilla genera, the content of this compound ranges from 1·37 to 1·96%. In seeds of Jacaratia , however, only 2–4 ppm of BITC was found. The striking quantitative differences suggest the possible use of BITC content as a chemotaxonomic criterion.
TL;DR: In this paper, a phylogenetic analysis based on nucleotide sequences from the ITS of the ribosomal DNA and three chloroplast fragments (matK, trnL−trnF, and psbA-trnH) was performed to clarify phylogenetic relationships and evolution within Caricaceae.
Abstract: This study focused on clarifying phylogenetic relationships and evolution within Caricaceae. Our phylogenetic analysis based on nucleotide sequences from the ITS of the ribosomal DNA and three chloroplast fragments (matK, trnL–trnF, and psbA–trnH) included 29 taxa belonging to five genera: the neotropical genera Carica, Vasconcellea, Jarilla, and Jacaratia and the equatorial African genus Cylicomorpha. Having a relatively low mutation rate, matK, and trnL–trnF were used for estimating relationships at the generic level, while intrageneric evolution within Vasconcellea was studied with the more variable ITS and psbA–trnH sequences. Gaps, coded as binary characters, were added to the sequence alignments before performing Maximum Parsimony and Maximum Likelihood analyses. Monophyly of Caricaceae as well as phylogenetic distance between Carica and Vasconcellea species, previously belonging to the same genus, and monophyly of the resurrected genus Vasconcellea were emphasized. Within Vasconcellea, the largest genus of this family, two well-confirmed evolutionary lineages could be discerned: (1) V. × heilbornii, V. weberbaueri, V. stipulata, and V. parviflora and (2) a clade holding all other taxa of the genus. Incongruence between nuclear ITS and chloroplast psbA–trnH datasets, shown to be significantly caused by some taxa of the genus Vasconcellea, indicated that reticulate events in this genus might be more frequent than previously suspected. Moreover, intra-individual ITS sequence heterogeneity provided further evidence for the hybrid or introgressed origin of different taxa and one presumed hybrid belonging to this genus.