Search results for "Aphid"
showing 10 items of 128 documents
Preliminary study on the biology, natural enemies and chemical control of the invasive Macrohomotoma gladiata (Kuwayama) on urban Ficus microcarpa L.…
2015
[EN] The phenology and natural enemies of Macrohomotoma gladiata (Kuwayama) (Hemiptera. Homotomidae) on Ficus microcarpa L. in Valencia (Spain) were studied in 2013. During the study, all immature instars of the pest were found on infested shoots indicating overlapping generations. However, two consistent increases in the proportion of the first two nymphal instars were detected in early March and June, possibly suggesting the beginning of spring and summer generations. Eggs of Macrohomotoma gladiata were usually found below the stipules of new healthy shoots, arranged in groups of 15-30 units. First two nymphal instars usually preferred the innermost part of the shoot, whereas the older de…
Transmission of PPV-M to Prunus persica by Brachycaudus schwartzi and Phorodon Humuli (Hem. Aphididae)
2004
Aphids are reported to be vectors of the most serious viral pathogen of the drupaceous species plum pox virus (PPV), but there is little direct experimental evidence of this. PPV (serotype M) is widespread in peach orchards even where there are severe control measures. Laboratory bioassays were conducted to study, under controlled conditions, the ability of Brachycaudus schwartzi (Borner) and Phorodon humuli (Schrank) to transmit PPV (serotype M). The results have shown that all the peach trees tested had evident symptoms of sharka and were positive to the RT-PCR analysis, confirming the ability of these two aphid species to transmit the virus.
Settling Down: The Genome of Serratia symbiotica from the Aphid Cinara tujafilina Zooms in on the Process of Accommodation to a Cooperative Intracell…
2014
Particularly interesting cases of mutualistic endosymbioses come from the establishment of co-obligate associations of more than one species of endosymbiotic bacteria. Throughout symbiotic accommodation from a free-living bacterium, passing through a facultative stage and ending as an obligate intracellular one, the symbiont experiences massive genomic losses and phenotypic adjustments. Here, we scrutinized the changes in the coevolution of Serratia symbiotica and Buchnera aphidicola endosymbionts in aphids, paying particular attention to the transformations undergone by S. symbiotica to become an obligate endosymbiont. Although it is already known that S. symbiotica is facultative in Acyrt…
Effects of essential oils of Origanum vulgare L. (Fam. Labiatee), Pelargonium odoratissimum L. (Fam. Geraniaceae) and Syzygium aromaticum L. (Fam. Mi…
2021
The cotton aphid, Aphis gossypii Glover (Homoptera: Aphidiidae), is a cosmopolitan and highly polyphagous species causing serious economic damage to numerous plants including Cucurbitaceae. The use of synthetic insecticides represent the main method of control of this aphid, often resulting in resistance to all the major insecticide group. The use of natural products, such as essential oils (EOs), has increased in recent years because they have advantages in reduction of this resistance. Within this research area, we have implement and evaluate the applications of EOs that aim at reinforcing knowledge on the control of this aphid. We investigated the topical application of the EOs of Origan…
An 18S rDNA-Based Molecular Phylogeny of Aphidiinae (Hymenoptera: Braconidae)
2000
We have obtained a molecular phylogeny of the subfamily Aphidiinae (Hymenoptera: Braconidae) by sequencing the 18S rDNA in 37 aphidiine taxa. Approximately 1857 nucleotides were sequenced in each species. Evolutionary relationships were established by comparing the results of maximum-parsimony, maximum-likelihood, and distance analyses. The most variable region of this gene, V4 (approx 403 nucleotides), was employed to establish the basality of the tribe Ephedrini within this subfamily. All phylogenetic reconstructions yielded trees with very similar topologies that confirmed the existence of two of the four traditionally accepted tribes, Ephedrini and Praini, but questioned the existence o…
Evolution of the Secondary Symbiont “Candidatus Serratia symbiotica” in Aphid Species of the Subfamily Lachninae ▿†
2008
ABSTRACT Buchnera aphidicola BCc, the primary endosymbiont of the aphid Cinara cedri (subfamily Lachninae), is losing its symbiotic capacity and might be replaced by the coresident “ Candidatus Serratia symbiotica.” Phylogenetic and morphological analyses within the subfamily Lachninae indicate two different “ Ca . Serratia symbiotica” lineages and support the longtime coevolution of both symbionts in C. cedri .
Two new records of Alloxysta (Hymenoptera: Cynipoidea: Figitidae: Charipinae) from Colombia
2016
The Charipinae from Colombia has been recently studied. Nine Charipinae species are known to be present in this country: Alloxysta arcuata (Kieffer, 1902), Alloxysta castanea (Hartig, 1841), Alloxysta consobrina (Zetterstedt, 1838), Alloxysta hansoni Pujade-Villar, 2011, Alloxysta obscurata (Hartig, 1840), Alloxysta medinae Ferrer-Suay & Pujade-Villar, 2012, Alloxysta pilipennis (Hartig, 1840), Alloxysta torresi Ferrer-Suay & Pujade-Villar, 2012 and Phaenoglyphis villosa (Hartig, 1841). Here more Charipinae material has been studied from collections made with Malaise traps by the Humboldt Institute in several places of Colombia. In this study, two species are recorded for the first …
The genus Troglophilus Krauss, 1879 (Orthoptera: Rhaphidophoridae) in the west Balkans
2011
We present a revision of the genus Troglophilus in the western part of the Balkan Peninsula based on morphological and genetic analysis, and provide distribution data for the species. The results of these analyses reduced the number of the known taxa within the genus Troglophilus in this area to five valid species: Troglophilus cavicola (Kollar, 1833), Troglophilus neglectusKrauss, 1879, Troglophilus ovuliformisKarny, 1907, Troglophilus brevicauda Chopard, 1934, and Troglophilus lazaropolensis Karaman, 1958. A new species Troglophilus zorae sp. nov. is described and Troglophilus neglectus serbicus Maran, 1958, Troglophilus neglectus vlasinensis Maran, 1958, Troglophilus bukoviki Karaman, 19…
Molecular characterization of cyclic and obligate parthenogens in the aphid Rhopalosiphum padi (L.)
1996
Holocyclic clones of the aphid Rhopalosiphum padi (L.) reproduce by cyclic parthenogenesis, whereas anholocyclic individuals are obligate parthenogens. Mitochondrial DNA (mtDNA) and random amplified polymorphic DNA markers in R . padi as well as plasmid DNA markers of its bacterial endosymbiont, Buchnera aphidicola , were examined to determine the extent of genetic divergence between clones with these differing breeding systems. These analyses revealed that cyclically parthenogenetic lineages possessed differing mtDNA and plasmid haplotypes than most obligately asexual clones. The extent of sequence divergence between these maternally inherited molecules suggests a relatively ancient origin…
Disentangling local agronomic practices from agricultural landscape effects on pest biological control
2019
International audience; The biological control of crop pests is a valuable service provided by various beneficial organisms that are naturally present in agricultural landscapes. Semi-natural habitats has long been recognized as essential to preserve beneficial insects, but proof of their efficiency to enhance biological control of pests remains non conclusive. Here, we examined the variability of landscape effect on biological pest control and the way local agronomic practices may modulate it. Biological pest control was monitored in 80 commercial fields (arable crops and orchards) during three consecutive years in four contrasting French agricultural landscapes distributed along a double …