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Pepper Crops (pepper + crop)
Selected AbstractsDevelopment of a biological control-based Integrated Pest Management method for Bemisia tabaci for protected sweet pepper cropsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2009F. J. Calvo Abstract The tobacco whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), is a key pest in commercial sweet pepper crops in southeast Spain. Its biological control is currently based on augmentative introductions of the parasitic wasp Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae), which need to be occasionally supplemented with pesticide applications. These pesticides can be harmful for the biological control agents. Therefore, it is important to improve the current strategy by reducing dependency on pesticides. Two potential solutions are conceivable: addition of another effective biocontrol agent or application of pesticide prior to the release of biocontrol agents. The mirid bug Nesidiocoris tenuis Reuter (Heteroptera: Miridae) and the predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) are promising candidates as additional biocontrol agents. The aim of the present study was to test these possible solutions in two subsequent trials, i.e., a ,selection' and an ,improvement' experiment. In the selection experiment, four treatments were compared: E. mundus, N. tenuis + E. mundus, A. swirskii + E. mundus, and A. swirskii + N. tenuis + E. mundus. Amblyseius swirskii appeared able to significantly increase effectiveness against the pest, in contrast to N. tenuis, which did not contribute to whitefly control. The best strategy was the combination of E. mundus and A. swirskii. In the improvement experiment, three treatments were compared: E. mundus, A. swirskii + E. mundus, and A. swirskii + E. mundus + pesticides. Amblyseius swirskii again proved capable of significantly reducing whitefly populations, and the implementation of pesticides before the release of the biocontrol agents was shown to increase the effectiveness against the pest even more. [source] Implications of phenotypic variation of Myzus persicae (Hemiptera: Aphididae) for biological control on greenhouse pepper plantsJOURNAL OF APPLIED ENTOMOLOGY, Issue 7 2009D. R. Gillespie Abstract Variation in vulnerability to natural enemies, reproductive rate and insecticide resistance among phenotypes of Myzus persicae (Sulzer) has been shown to have the potential to disrupt biological control and IPM of this species, and movement of particularly troublesome phenotypes in international horticultural trade could be cause for concern. Three important components of fitness, vulnerability to parasitoids, reproduction and insecticide resistance were determined in three clones of M. persicae originating from prevalent phenotype populations on pepper crops in greenhouses in British Columbia, Canada. One of these phenotypes appeared to be consistently involved in outbreaks in commercial operations. These clones were also characterized for their DNA microsatellite genotype and compared with genotypes of M. persicae from Europe. The clone involved in outbreaks in commercial greenhouses showed reduced vulnerability to parasitoids, and a higher reproductive rate compared to the other two clones suggesting that these traits may have been involved in outbreaks. As in M. persicae European clones, a higher reproductive rate was correlated with a lack of esterase-based resistance (primarily to organophosphates and, to some extent, to carbamates and pyrethroids). However, microsatellite analysis demonstrated that the three clones investigated in British Columbia had unique genotypes, and therefore there was no evidence for their movement in international trade. [source] Association of MACE-based insecticide resistance in Myzus persicae with reproductive rate, response to alarm pheromone and vulnerability to attack by Aphidius colemaniPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 11 2003Stephen P Foster Abstract Reproductive success and response to alarm pheromone, both potentially important components of fitness, were assessed using clones of Myzus persicae (Sulzer) to establish associations with insecticide resistance conferred by insensitive modified acetylcholinesterase (MACE). Both traits showed significant trends that were apparently related to this mechanism. MACE forms appeared to reproduce at slower rates than non-MACE forms expressing moderate (R1) levels of another resistance mechanism based on elevated carboxylesterase. However, MACE forms were more responsive to alarm pheromone than their non-MACE counterparts. The potential implications for parasitoid performance were tested using two clones showing clear differences in alarm response. The level of parasitism of M persicae by the parasitoid Aphidius colemani (Viereck) was significantly lower in MACE forms on pepper crops compared to non-MACE forms. In addition, the distribution of MACE and non-MACE forms differed on the pepper plants, with more MACE forms being found on the growing points. The presence of the parasitoid A colemani did not alter this change in distribution. Copyright © 2003 Society of Chemical Industry [source] | ||||||||||