Search results for "LEPIDOPTERA"
showing 10 items of 191 documents
From non-target risk assessment to Bt resistance management: the example of Bt Brassica sp. and Pieridae
2011
Insecticidal toxins produced by Bacillus thuringiensis (Bt) have been widely used in plant protection in two different ways: 1) by spraying bacterial Bt formulations, 2) by expressing their gene encoding in planta. In the second strategy, only the transgenic plants themselves are protected but insect- resistant plants could spread into natural habitats and/or the gene could be fixed in alternative hosts. It is necessary to estimate the magnitude of the possible effects on naturally occurring herbivorous insects but also on the target species, especially when they have several alternative hosts, as in the case of Pieridae. They are present both in agriculture where they could be considered p…
Microbial Diversity in the Midguts of Field and Lab-Reared Populations of the European Corn Borer Ostrinia nubilalis
2011
Background: Insects are associated with microorganisms that contribute to the digestion and processing of nutrients. The European Corn Borer (ECB) is a moth present world-wide, causing severe economical damage as a pest on corn and other crops. In the present work, we give a detailed view of the complexity of the microorganisms forming the ECB midgut microbiota with the objective of comparing the biodiversity of the midgut-associated microbiota and explore their potential as a source of genes and enzymes with biotechnological applications. Methodological/Principal Findings: A high-throughput sequencing approach has been used to identify bacterial species, genes and metabolic pathways, parti…
Microbial communities of lycaenid butterflies do not correlate with larval diet
2016
Herbivores possess many counteradaptations to plant defenses, and a growing body of research describes the role of symbiotic gut bacteria in mediating herbivorous diets among insects. However, persistent bacterial symbioses have not been found in Lepidoptera, despite the fact that perhaps 99% of the species in this order are herbivorous. We surveyed bacterial communities in the guts of larvae from 31 species of lycaenid butterflies whose caterpillars had diets ranging from obligate carnivory to strict herbivory. Contrary to our expectations, we found that the bacterial communities of carnivorous and herbivorous caterpillars do not differ in richness, diversity, or composition. Many of the o…
Can Mating Disruption Be a Possible Route to Control Plum Fruit Moth in Mediterranean Environments?
2020
Simple Summary Grapholita funebrana is a main pest of plum throughout the Palearctic region. The management of this pest is generally carried out with chemical insecticides. In this study we investigated the suitability of the mating disruption as alternative method of control of this pest. Experiments were carried out in organic plum orchards during 2012 and 2014. Trap catches and fruit sampling were carried out to estimate the efficacy of this technique in reducing males catch and fruit infestation. The results indicated that the males caught in traps placed in the treatment plots was always significantly lower than untreated plots. The chemical analysis of the pheromone emission from the…
Re-examining the rare and the lost : a review of fossil Tortricidae (Lepidoptera)
2018
We re-evaluate eleven fossils that have previously been assigned to the family Tortricidae, describe one additional fossil, and assess whether observable morphological features warrant confident assignment of these specimens to this family. We provide an overview of the age and origin of the fossils and comment on their contribution towards understanding the phylogeny of the Lepidoptera. Our results show that only one specimen, Antiquatortia histuroides Brown & Baixeras gen. and sp. nov., shows a character considered synapomorphic for the family. Six other fossils ( Electresia zalesskii Kusnezov, 1941; Tortricidrosis inclusa Skalski, 1973; Tortricites skalskii Kozlov, 1988; Tortricibaltia d…
Hylotelephium spectabile, a New Host for Carnation Tortrix Moth (Cacoecimorpha pronubana) and Molecular Characterization in Greece
2021
Simple Summary Hylotelephium spectabile (Saxifragales, Crassulaceae), a widespread ornamental plant was found infested by larvae of Cacoecimorpha pronubana (Lepidoptera, Tortricidae) a highly polyphagous pest of a wide range of crop, as well as ornamental plants. To the best of our knowledge, this finding suggests that H. spectabile should be considered a new host plant for C. pronubana. Moreover, molecular characterization of the Greek pest population place it along with European species clade. Abstract Cacoecimorpha pronubana (Hübner) (Lepidoptera, Tortricidae) is a highly polyphagous pest of a wide range of crop and ornamental plants. It is of Mediterranean origin and widespread in Europ…
Study of the bacillus thuringiensis Cry1Ia protein oligomerization promoted by midgut brush border membrane vesicles of lepidopteran and coleopteran …
2020
Bacillus thuringiensis (Bt) produces insecticidal proteins that are either secreted during the vegetative growth phase or accumulated in the crystal inclusions (Cry proteins) in the stationary phase. Cry1I proteins share the three domain (3D) structure typical of crystal proteins but are secreted to the media early in the stationary growth phase. In the generally accepted mode of action of 3D Cry proteins (sequential binding model), the formation of an oligomer (tetramer) has been described as a major step, necessary for pore formation and subsequent toxicity. To know if this could be extended to Cry1I proteins, the formation of Cry1Ia oligomers was studied by Western blot, after the incuba…
An Insight in the Reproductive Biology of Therophilus javanus (Hymenoptera, Braconidae, and Agathidinae), a Potential Biological Control Agent agains…
2017
Therophilus javanus is a koinobiont, solitary larval endoparasitoid currently being considered as a biological control agent against the pod borer Maruca vitrata, a devastating cowpea pest causing 20–80% crop losses in West Africa. We investigated ovary morphology and anatomy, oogenesis, potential fecundity, and egg load in T. javanus, as well as the effect of factors such as age of the female and parasitoid/host size at oviposition on egg load. The number of ovarioles was found to be variable and significantly influenced by the age/size of the M. vitrata caterpillar when parasitized. Egg load also was strongly influenced by both the instar of M. vitrata caterpillar at the moment of parasit…
New records of gall-inducer and inquiline insects in a few mediterranean countries, with biological notes
2014
An annotated list of some gall-inducing and inquiline insects found on herbaceous plants and trees in Italy and in other few Mediterranean countries is reported. Among the gall-inducer species, Phanacis phoenixopodos (Mayr, 1882) is new for the Italian peninsula, Callirhytis rufescens (Mayr, 1882), Andricus quercusramuli (L., 1761) and Plagiotrochus amenti Kieffer, 1901 (Cynipidae: Hymenoptera) are new for Sicily; the latter was previously cited from Italy without collecting data. Oecocecis guyonella Guenée, 1870 was found in Libya and Amblypalpis olivierella Ragonot, 1886 (Gelechiidae: Lepidoptera) in Jordan, Libya, Northern Yemen, and the United Arab Emirates. In addition, Saphonecrus gal…
Susceptibility of Grapholita molesta (Busck, 1916) to formulations of Bacillus thuringiensis, individual toxins and their mixtures.
2016
The Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of fruit trees worldwide, such as peach and apple. Bacillus thuringiensis has been shown to be an efficient alternative to synthetic insecticides in the control of many agricultural pests. The objective of this study was to evaluate the effectiveness of B. thuringiensis individual toxins and their mixtures for the control of G. molesta. Bioassays were performed with Cry1Aa, Cry1Ac, Cry1Ca, Vip3Aa, Vip3Af and Vip3Ca, as well as with the commercial products DiPel® and XenTari®. The most active proteins were Vip3Aa and Cry1Aa, with LC50 values of 1.8 and 7.5ng/cm2, respectively. Vip3Ca was nontoxic to this …