BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
The new species Rhopalosiphum chusqueae Pérez Hidalgo & Villalobos Muller, is described from apterous viviparous females caught on Chusquea tomentosa in Cerro de la Muerte (Costa Rica). The identity of the species is supported both by the morphological features and by a molecular phylogenetic analysis based on a fragment of the mitochondrial DNA containing the 5’ region of the cytochrome c oxidase 1 (COI) and on the nuclear gene coding for the Elongation factor-1 alpha (EF1α). The taxonomic position of the new species is discussed. An identification key to the Aphidinae species living on plants of Bambusoideae (Poaceae) is presented.
Guacimo trees (Guazuma ulmifolia, Sterculiaceae) showing witches' broom symptoms (GWB), small leaves, short internodes, stunting and no flower and fruit production were observed on side roads and fences in different areas of Costa Rica. The occurrence of phytoplasma infection in GWB trees was evaluated by transmission electron microscopy (TEM), and by molecular analyses based on 16S rDNA: nested-PCR/RFLP, sequencing and phylogenetics. Phytoplasmas were observed only in the sieve cells of symptomatic trees by TEM. The infection was confirmed by nested-PCR; amplicons of about 1.2 kb were obtained from all DNA samples from symptomatic trees. The RFLP analysis generated patterns identical among GWB samples and showed a relationship of this phytoplasma to hibiscus witches' broom group (16SrXV). The 16S rDNA sequence (1460 nt), obtained from the P1A/16S-SR semi-nested-PCR products of two phytoplasma strains, shared 98.8% similarity with 'Candidatus Phytoplasma brasiliense' (GenBank accession: AF147708). The virtual RFLP pattern indicated a similarity coefficient of 0.95 with 16Sr group XV-A (AF147708), suggesting that the GWB phytoplasma may represent a new subgroup within this group. This is the first report of a phytoplasma infecting the neotropical tree species G. ulmifolia and the natural occurrence of a phytoplasma strain closely related to 'Ca. Phytoplasma brasiliense' in Costa Rica. Key words: 'Ca. Phytoplasma brasiliense', 16S rRNA, guacimo witches'-broom, nested-PCR, RFLP. RESUMEN Guazuma ulmifolia (Sterculiaceae), un nuevo hospedero natural de fitoplasmas del grupo 16SrXV en Costa RicaEn varias zonas de Costa Rica se observaron árboles de guácimo (Guazuma ulmifolia, Sterculiaceae) con síntomas de escoba de bruja (GWB), hoja pequeña, acortamiento de entrenudos, dando al árbol un aspecto general de enanismo. La infección por fitoplasmas en los árboles de guácimo se evaluó mediante microscopia electrónica de transmisión (TEM), análisis moleculares del 16S rDNA mediante PCR anidado, RFLP´s, secuenciación y filogenia. En la TEM, los fitoplasmas se observaron sólo en las células del floema de los árboles sintomáticos. La infección se confirmó por PCR anidada, los productos amplificados de aproximadamente 1,2 kb se obtuvieron para todas las muestras sintomáticas evaluadas. El análisis de RFLP generó patrones idénticos entre las muestras con GWB y mostró relación de este fitoplasma con el de la "escoba de bruja del hibisco" (16SrXV). La secuencia de ADNr 16S (1460 nt) de los productos obtenidos por PCR semi-anidado (P1A/16S-SR) de dos muestras de GWB mostraron 98,8% de similitud con "Candidatus Phytoplasma brasiliense" (GenBank, registro AF147708). El patrón RFLP virtual reveló 95% de similitud con el grupo 16Sr XV-A (AF147708), lo que sugiere que el fitoplasma GWB puede representar un nuevo subgrupo dentro del 16Sr XV. Este es el primer informe de un fitoplasma infectando a la especie neotropical G. ulmifolia y de la ocurrencia natural de un fitoplasma estrechamente relacionado con "Ca. Phytoplasma brasili...
Abstract-Aphid species colonising ferns belong to the subfamily Aphidinae (Hemiptera: Aphididae) and the majority of these to the tribe Macrosiphini. A new genus in this tribe and its type species: Gibbomyzus pteridophytorum new genus, new species, are established. Apterous and alate viviparous females are described from specimens collected on Blechnum buchtienii Rosenstock (Blechnaceae) in Costa Rica and on Pteridium aquilinum (Linnaeus) Kuhn (Dennstaedtiaceae) and an unidentified fern in Mexico. The taxonomic validity of the two new taxa is discussed based on morphological and molecular data. Morphologically, the new genus is compared with genera with swollen siphunculi recorded in the New World, and also with genera living on ferns anywhere in the world. The identification key by Blackman and Eastop to aphids living on ferns is modified. Molecular analyses were carried out on the sequences of a fragment of the mitochondrial gene encoding for cytochrome c oxidase subunit 1 and of a fragment of the nuclear gene encoding elongation factor-1 alpha. In both analyses, G. pteridophytorum new species sequences showed considerable divergence (,4% or more) from those of 23 other species from diverse genera of Macrosiphini, supporting the conclusions of the morphological study and justifying the establishment of the new genus.Résumé-Les espèces de pucerons qui colonisent des fougères appartiennent à la sous-famille Aphidinae (Hemiptera: Aphididae) et la majorité d'entre elles à la tribu Macrosiphini. Un nouveau genre de cette tribu et son espèce typique sont établis : Gibbomyzus pteridophytorum, nouveau genre, nouvelle espèce, avec la description des femelles vivipares aptères et ailées collectées sur Blechnum buchtienii Rosenstock (Blechnaceae) au Costa Rica, et sur Pteridium aquilinum (Linnaeus) Kuhn (Dennstaedtiaceae) et une fougère non identifiée au Mexique. La validité taxonomique des deux nouveaux taxons est discutée morphologiquement par la comparaison du nouveau genre avec des genres cités en Amérique qui présentent des cornicules gonflées, et des genres qui habitent sur des fougères dans n'importe quelle partie du monde. Une modification de la clé d'identification de Blackman et Eastop pour les pucerons qui habitent sur les fougères est présentée. Des analyses moléculaires ont été réalisées sur les séquences d'un fragment du gène mitochondrial qui code pour la sous-unité 1 du cytochrome oxydase et d'un fragment du gène nucléaire qui code pour le facteur d'élongation 1 alpha. Dans les deux analyses les séquences de G. pteridophytorum nouvelle espèce ont une divergence considérable (4% ou plus) avec celles de 23 espèces de plusieurs genres de Macrosiphini, en appuyant les conclusions de l'étude morphologique, et en justifiant qu'un nouveau genre soit établi.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.