CABI

About: CABI is a nonprofit organization based out in Wallingford, United Kingdom. It is known for research contribution in the topics: Population & Introduced species. The organization has 789 authors who have published 1759 publications receiving 73843 citations. The organization is also known as: Centre for Biosciences and Agriculture International.

Host Volatile Attractants and Traps for Detection of Tetropium fuscum (F.), Tetropium castaneum L., and Other Longhorned Beetles (Coleoptera: Cerambycidae)

Abstract: Cortical and sapwood volatiles were collected in situ from red spruce, Picea rubens (Sarg.), trees infested with Tetropium fuscum (F.), to determine the relative concentrations and enantiomer ratios of monoterpenes emitted. This information was used to create a synthetic “spruce blend” lure that was tested in various trap designs for efficacy in capturing T. fuscum, and Tetropium castaneum L. in field bioassays conducted on McNabs Island, Nova Scotia, in 2001 and 2002 and in Poland and Switzerland in 2002. Response of other cerambycid species was measured opportunistically. Cross-vane pan traps baited with spruce blend caught significantly more T. fuscum than unbaited traps or traps baited with racemic α-pinene, ethanol, or both. The addition of an ethanol lure to spruce blend–baited traps significantly increased capture of T. fuscum and T. castaneum. There were no significant differences among trap designs in mean catch of either Tetropium species. Spruce blend was also significantly attractive ...

Evolutionary Relationships among Aspergillus Species Producing Economically Important Mycotoxins

Abstract: Summary Several mycotoxins are produced by aspergilli, which contaminate our foods and feeds. Economically the most important of these mycotoxins are aflatoxins, ochratoxins and patulin. Recent studies indicate that these compounds can be produced by a number of unrelated Aspergillus species. Evolutionary relationships among sections involving these mycotoxin producing species (Aspergillus sections Circumdati, Flavi, Nigri, Fumigati and Clavati) were evaluated using phylogenetic analysis of -tubulin and ribosomal RNA gene sequences. Phylogenetically unrelated species were found to produce the same mycotoxins. For example, aflatoxins have been produced under laboratory conditions by species belonging to three different sections, while ochratoxin A (OA) and patulin have been produced by a variety of unrelated species. Based on this observation, mycotoxin-producing abilities of the isolates were lost (or gained) several times during the evolution of the genus. Previous studies revealed that biosynthetic genes of several mycotoxins are clustered in the genome, leading to the idea that these clusters could be horizontally transferred as a unit to unrelated species, leading to the biosynthesis of the same mycotoxins in phylogenetically unrelated fungi. Such a mechanism could also explain the widespread occurrence of ochratoxin and patulin production in aspergilli. The organisation of biosynthetic genes of patulin and ochratoxins is unknown. Research is in progress in our laboratory to clarify the genetic background of biosynthesis of these mycotoxins, and to develop biosynthetic gene based probes for the molecular detection of these mycotoxin-producing organisms.

Experimental and molecular evidence of Reptalus panzeri as a natural vector of bois noir

Abstract: Bois noir (BN) is an economically important grapevine yellows disease induced by the stolbur phytoplasma and principally vectored by the cixiid Hyalesthes obsoletus. This study addresses the involvement of other planthoppers and/or leafhoppers in BN epidemics in the South Banat district of northeastern Serbia, by performing transmission experiments and multilocus typing of stolbur phytoplasma isolates to determine the vector-related characteristics of the disease. Transmission trials were conducted with adults of two cixiid congeners, Reptalus panzeri and R. quinquecostatus, which were found to harbour stolbur phytoplasma in the vineyards under study. A molecular characterization of stolbur phytoplasma isolates was performed by sequence analysis and/or RFLP typing of the two housekeeping genes tuf and secY and the two membrane proteins stamp and vmp1. Transmission trials with naturally infected R. panzeri adults from either the BN-infected vineyards or maize redness (MR)-affected maize fields revealed a high stolbur phytoplasma transmission efficiency to grapevines. In contrast, experiments conducted with stolbur-positive R. quinquecostatus originating from BN-infected vineyards, provided no evidence for a vector role of this species. Seven stolbur phytoplasma genotypes, all of which were tuf-b types, were detected among the grapevine- and insect-associated field samples according to the tuf/secY/vmp1/stamp typing. STOLg was the genotype most frequently found in naturally infected grapevine (42%), as well as R. panzeri originating from the vineyards (85%) and maize fields (98%). The same genotype was found in all experimental plants inoculated by R. panzeri, confirming its vectorship of the disease.

Summer drought alters plant-mediated competition between foliar- and root-feeding insects

Abstract: Summer droughts are predicted to increase in severity and frequency in the United Kingdom, due to climate change. Few studies have addressed the impacts of drought on interactions between species, and the majority have focussed on increases in CO2 concentration and changes in temperature. Here, the effect of experimental summer drought on the strength of the plant-mediated interaction between leaf-mining Stephensia brunnichella larvae and root-chewing Agriotes larvae was investigated. Agriotes larvae reduced the abundance and performance of S. brunnichella feeding on a mutual host plant, Clinopodium vulgare, as well as the rate of parasitism of the leaf-miner. The interaction did not, however, occur on plants subjected to a severe drought treatment, which were reduced in size. Changes to summer rainfall, due to climate change, may therefore reduce the occurrence of plant-mediated interactions between insect herbivores.

Telenomus remus, a Candidate Parasitoid for the Biological Control of Spodoptera frugiperda in Africa, is already Present on the Continent

Abstract: The fall armyworm, Spodoptera frugiperda, a moth originating from tropical and subtropical America, has recently become a serious pest of cereals in sub-Saharan Africa. Biological control offers an economically and environmentally safer alternative to synthetic insecticides that are being used for the management of this pest. Consequently, various biological control options are being considered, including the introduction of Telenomus remus, the main egg parasitoid of S. frugiperda in the Americas, where it is already used in augmentative biological control programmes. During surveys in South, West, and East Africa, parasitized egg masses of S. frugiperda were collected, and the emerged parasitoids were identified through morphological observations and molecular analyses as T. remus. The presence of T. remus in Africa in at least five countries provides a great opportunity to develop augmentative biological control methods and register the parasitoid against S. frugiperda. Surveys should be carried out throughout Africa to assess the present distribution of T. remus on the continent, and the parasitoid could be re-distributed in the regions where it is absent, following national and international regulations. Classical biological control should focus on the importation of larval parasitoids from the Americas.