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Colorado Potato Beetle (colorado + potato_beetle)
Selected AbstractsChoosing natural enemies for conservation biological control: use of the prey detectability half-life to rank key predators of Colorado potato beetleENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2010Matthew H. Greenstone Abstract Determining relative strengths of trophic links is critical for ranking predators for conservation biological control. Molecular gut-content analysis enables ranking by incidence of prey remains in the gut, but differential digestive rates bias such rankings toward predators with slower rates. This bias can be reduced by indexing each predator's half-life to that of the middle-most half-life in a predator complex. We demonstrate this with data from key species in the predator complex of Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), comprising adults and immatures of four taxonomically diverse species. These animals display order-of-magnitude variation in detectability half-life for the cytochrome oxidase I DNA sequence of a single CPB egg: from 7.0 h in larval Coleomegilla maculata (DeGeer) (Coleoptera: Coccinellidae) to 84.4 h in nymphal Perillus bioculatus (Fabricius) (Hemiptera: Pentatomidae). The raw species-specific incidence of L. decemlineata DNA in the guts of 351 field-collected predators ranged from 11 to 95%, ranking them as follows: C. maculata adults < Lebia grandis Hentz (Coleoptera: Carabidae) adults < Podisus maculiventris (Say) (Hemiptera: Pentatomidae) adults < P. maculiventris nymphs < P. bioculatus adults < P. bioculatus nymphs. Half-life adjustment reorders the rankings: C. maculata adults < P. bioculatus adults < P. bioculatus nymphs < P. maculiventris nymphs < L. grandis adults < P. maculiventris adults. These changes in status demonstrate the value of half-life-adjusted molecular gut-content data for ranking predators. This is the first study to measure prey detectability half-lives for the key arthropod predators of a major insect pest, and to use them to evaluate the relative impact of all adults and immatures in this predator complex. [source] Genetic analysis of larval survival and larval growth of two populations of Leptinotarsa decemlineata on tomatoENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2001Wenhua Lu Abstract The genetics of adaptation to tomato in Leptinotarsa decemlineata (Say) were investigated in reciprocal F1, F2, and backcross populations generated from crosses between beetles from a tomato adapted population and from a population that was poorly adapted to tomato. Larvae from the parent and test populations were reared on tomato for four days, after which survivorship and larval weights were recorded. Most results indicate that differences in larval growth and survival on tomato between the parent populations are largely determined by autosomal, polygenic mechanisms, the inheritance of which involves a significant dominance component. However, results from F2 crosses are not consistent with this conclusion. A significant difference in larval weights, but not in survival, between reciprocal F1 populations in an analysis of combined data from four separate experiments suggests that maternal cytoplasmic effects may contribute to differences in larval performance on tomato between the adapted and unadapted populations. The unusual results obtained from F2 crosses in this study are not atypical of results from previous studies of the genetics of adaptation to host plants by the Colorado potato beetle. Host plant adaptation by Colorado potato beetles may therefore involve unusual genetic mechanisms that are not easily assessed by classical Mendelian analysis. [source] Problems of resistance development in arthropod pests of agricultural crops in RussiaEPPO BULLETIN, Issue 1 2008G. I. Sukhoruchenko This paper presents the results of long-term monitoring of insecticide resistance in populations of agricultural pests in Russia. Over the last 45 years, resistance developments were recorded for 36 arthropod pest species in 11 agricultural crops and pastures in relation to nearly all commonly used plant protection products. Development of group, cross and multiple resistance has been revealed in populations of many economically important pests. Toxicological and phenotypical (for Colorado potato beetle) methods have been devised to monitor the development of pesticide resistance. Based on experience over the last century, systems aimed at preventing the development of pest resistance to insecticides and acaricides are elaborated. These systems are based on resistance monitoring and using plant protection measures which minimize the toxic pressure on agroecosystems. [source] Properties of ecdysteroid receptors from diverse insect species in a heterologous cell culture system , a basis for screening novel insecticidal candidatesFEBS JOURNAL, Issue 11 2009Joshua M. Beatty Insect development is driven by the action of ecdysteroids on morphogenetic processes. The classic ecdysteroid receptor is a protein heterodimer composed of two nuclear receptors, the ecdysone receptor (EcR) and Ultraspiracle (USP), the insect ortholog of retinoid X receptor. The functional properties of EcR and USP vary among insect species, and provide a basis for identifying novel and species-specific insecticidal candidates that disrupt this receptor's normal activity. A heterologous mammalian cell culture assay was used to assess the transcriptional activity of the heterodimeric ecdysteroid receptor from species representing two major insect orders: the fruit fly, Drosophila melanogaster (Diptera), and the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera). Several nonsteroidal agonists evoked a strong response with the L. decemlineata heterodimer that was consistent with biochemical and in vivo evidence, whereas the D. melanogaster receptor's response was comparatively modest. Conversely, the phytoecdysteroid muristerone A was more potent with the D. melanogaster heterodimer. The additional presence of juvenile hormone III potentiated the inductive activity of muristerone A in the receptors from both species, but juvenile hormone III was unable to potentiate the inductive activity of the diacylhydrazine methoxyfenozide (RH2485) in the receptor of either species. The effects of USP on ecdysteroid-regulated transcriptional activity also varied between the two species. When it was tested with D. melanogaster EcR isoforms, basal activity was lower and ligand-dependent activity was higher with L. decemlineata USP than with D. melanogaster USP. Generally, the species-based differences validate the use of the cell culture assay screen for novel agonists and potentiators as species-targeted insecticidal candidates. [source] Environmental stresses induce the expression of putative glycine-rich insect cuticular protein genes in adult Leptinotarsa decemlineata (Say)INSECT MOLECULAR BIOLOGY, Issue 3 2008J. Zhang Abstract The deposition of cuticular proteins in insects usually occurs during the moulting process. Three putative glycine-rich insect cuticular proteins, Ld-GRP1 to 3, were identified and characterized from the Colorado potato beetle, Leptinotarsa decemlineata. The Ld-GRPs contained conserved GXGX and/or GGXG sequence repeats. Ld-GRP1 also contained a conserved AAPA/V motif commonly found in cuticular proteins. The transcripts of Ld-GRP1 and Ld-GRP2 were detected in the epidermal cell layer by in situ hybridization, making them putative insect cuticular proteins. The putative cuticular protein genes were highly induced by the insecticide azinphosmethyl (organophosphorous) 2,3 weeks after adult moulting. Putative cuticular protein gene expression level was higher in azinphosmethyl-resistant beetles than in susceptible beetles. Furthermore, two of the putative cuticular protein genes were highly induced by dry environmental conditions. These results suggest that the insect might increase cuticular component deposition in the adult stage in response to environmental stresses. This ability may allow the insect to adapt to new or changing environments. [source] Compatibility of a natural enemy, Coleomegilla maculata lengi (Col., Coccinellidae) and four insecticides used against the Colorado potato beetle (Col., Chrysomelidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 3 2004É. Lucas Abstract:, ,The toxicity of four insecticides used to control the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), imidacloprid (Admire®), cryolite (Kryocide®), cyromazine (Trigard®), and Bacillus thuringiensis var. tenebrionis (Novodor®), to one of its natural enemies, the 12-spotted lady beetle, Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae) was determined in the laboratory. Toxicity assays against C. maculata adults and larvae consisted of (1) topical applications and (2) exposures to treated foliage and prey, using concentrations up to 10 times the manufacturer's recommendations. Over a 6-day period, cyromazine (insect growth regulator) and B. t. var. tenebrionis (microbial insecticide) had no lethal effects on first and third instars C. maculata. For both larval and adult stages, cryolite (inorganic insecticide) caused very low predator mortality when topically applied and moderate mortality when ingested through contaminated eggs of Colorado potato beetles. Imidacloprid (systemic organic insecticide) was highly toxic to adult and larval C. maculata. Its estimated LD50 at 6 days following treatment, corresponded to 0.02,0.09 times the recommended field concentration, depending on the developmental stage and mode of contamination. These results indicate that integrated pest management programmes for Colorado potato beetles using imidacloprid or, to a lesser degree, cryolite, would be detrimental to C. maculata. Cyromazine and B. t. var. tenebrionis seem to present a better compatibility with the protection of C. maculata populations. [source] Use of sperm precedence to infer the overwintering cost of insecticide resistance in the Colorado potato beetleAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2008Mitchell B. Baker Abstract 1,Resistance to insecticides is a model system for studying adaptation. Although selection for resistance is always strong in areas and seasons where populations are exposed to insecticides, costs of resistance, which may only be expressed in the absence of insecticide use, will shape how quickly resistance will evolve. 2,We used sperm precedence to measure the shifts in resistance to imidacloprid in a natural population during winter diapause in the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae). Because adult beetles overwinter with viable autumn sperm, but sperm from spring matings take precedence over stored sperm, we used the difference in resistance of springmated and autumn-mated overwintered females to estimate the shift in resistance during the winter. Offspring of autumn-mated females were 2.7- or 2.5-fold more resistant compared with offspring from spring-mated females in two replicate trials. 3,We also measured the resistance of late summer and spring emergent adults in fields treated and untreated with imidacloprid in the first year. Adults from the treated field were 13.7-fold more resistant and adults from the untreated field were 2.6-fold more resistant compared with the next spring's emergers. 4,These large costs of resistance observed in the field and inferred from resistance declines during diapause help to explain the observation that imidacloprid resistance has increased only slowly over the decade of widespread use against this species, and how insecticide resistance in general can cycle annually. [source] Potential of a synthetic aggregation pheromone for integrated pest management of Colorado potato beetleAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2006T. P. Kuhar Abstract 1The relative number of colonizing adult Colorado potato beetles (CPB) Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) coming to pitfall traps baited with the aggregation pheromone (S)-3,7-dimethyl-2-oxo-oct-6-ene-1,3-diol [(S)-CPB I] and the use of the pheromone in a trap crop pest management strategy were evaluated in the field for the first time. 2More than five-fold more adult L. decemlineata were caught in pitfall traps baited with the pheromone compared with controls. However, attraction to the pheromone diminished after 5 days in the field. 3In the trap crop management strategy, more colonizing adults were present in pheromone-treated rows of potatoes compared with untreated middle rows. 4Significantly fewer L. decemlineata egg masses and larvae were found in potato plots that were bordered by pheromone-treated rows, or bordered by imidacloprid + pheromone-treated rows, or rows treated at-planting with imidacloprid compared with untreated (control) potato plots. 5Densities of L. decemlineata egg masses and larvae and percentage defoliation were significantly lower, and marketable tuber yield significantly higher, in conventional imidacloprid-treated potatoes compared with all other treatments. 6Although our results demonstrate the potential for use of the aggregation pheromone in the management of L. decemlineata in the field, more research is needed to optimize the release rates of the attractant and incorporate control methods for cohabiting pests. [source] Horizontal transmission of Beauveria bassiana (Bals.) VuillAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2000David W. Long Summary 1 Factors influencing horizontal transmission of the entomopathogen Beauveria bassiana in the Colorado potato beetle (CPB) were examined through a series of laboratory studies. 2 Cadaver density, cadaver life stage, ambient temperature and conidial density were the factors manipulated. 3 Mortality and sporulation of burrowing CPB prepupae both increased significantly with increased sporulating second-instar cadaver density on the soil surface. 4 Mortality rates were significantly higher when prepupae were released into laboratory arenas containing third-instar cadavers compared to second-instar cadavers. 5 Mortality and sporulation decreased significantly as temperature increased from 15 °C to 30 °C, however, no temperature-dependent behavioural response by prepupae could be identified as a potential cause. 6 An 86.1% decrease in conidial density per cadaver had no significant effect on mortality or sporulation of prepupae, indicating that this level of environmental degradation of cadavers may not significantly reduce the probability of horizontal transmission. [source] DNA-based genotyping techniques for the detection of point mutations associated with insecticide resistance in Colorado potato beetle Leptinotarsa decemlineata,PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 10 2001J Marshall Clark Abstract Three DNA-based genotyping techniques, bi-directional PCR amplification of specific allele (bi-PASA), single-stranded conformational polymorphism (SSCP) and minisequencing, have been developed and compared for the detection of the S291G (insensitive acetylcholinesterase) and L1014F (insensitive sodium channel) mutations associated with azinphos-methyl and permethrin resistance, respectively, in the Colorado potato beetle (Leptinotarsa decemlineata). Extraction of genomic DNA from individual neonates that were hatched from previously collected egg masses is the most efficient and reliable means to obtain suitable templates in terms of convenience, economy, speed and DNA quality. Bi-PASA, employing two allele-specific primers, appears to be the most efficient and rapid genotyping method for the simultaneous detection of both resistant/susceptible homozygous (SS, RR) and heterozygous (SR) alleles. Its resolution, however, is strongly dependent on the quality of template genomic DNA. SSCP also allows unambiguous genotyping, including the detection of heterozygous alleles, and is less dependent on template DNA quality, but requires a longer processing time. Minisequencing is amenable to a 96-well microtiter plate format for the processing of a large number of samples and allows direct detection of resistant/susceptible homozygous alleles but is not as efficient as the PASA and SSCP in detecting heterozygous alleles. In considering the advantages and disadvantages of each technique, DNA-based genotyping is best employed in combinations, with the bi-PASA as the primary method and the SSCP and minisequencing as the secondary validating methods. These methods are rugged, rapid, cost-effective and capable of resolving SS, RR and SR individuals. The availability of such DNA-based genotyping techniques, using neonate genomic DNA as templates, will enable the precise monitoring of the resistant and susceptible allele frequencies, including those of heterozygote individuals, in field populations of L decemlineata. © 2001 Society of Chemical Industry [source] Biological performance of Myzus persicae and Macrosiphum euphorbiae (Homoptera: Aphididae) on seven wild Solanum speciesANNALS OF APPLIED BIOLOGY, Issue 3 2010Y. Pelletier Resistance level of seven accessions of wild Solanum species (Solanaceae) to Myzus persicae and Macrosiphum euphorbiae (Homoptera: Aphididae) was evaluated by measuring survival and fecundity during sleeve cage experiments and population growth on whole plants in a controlled environment. The survival was lowest on the Solanum circaeifolium spp. capsicibaccatum, Solanum pinnatisectum and Solanum trifidum accessions for M. persicae and on the S. circaeifolium spp. capsicibaccatum, Solanum okadae and S. trifidum, accessions with M. euphorbiae. Plant species significantly influenced the fecundity of both aphid species. Aphid population growth on whole plants was negatively affected by the age of the plant, but generally followed the levels of net reproductive rate on different plant species observed during the sleeve cage experiment. The population of M. persicae varied among the seven wild potato accessions with the lowest growth rates on S. circaeifolium spp. capsicibaccatum, Solanum polyadenium, Solanum tarijense and S. trifidum. The number of M. euphorbiae also varied among accessions but the smallest population was collected from S. polyadenium. The results can be used to identify sources of resistance to aphids within those accessions already known to be resistant to the Colorado potato beetle. This study highlights the difficulties involved in developing a high-throughput screening test for aphid resistance compatible with a potato breeding programme. [source] Plant extract contact toxicities to various developmental stages of Colorado potato beetles (Coleoptera: Chrysomelidae)ANNALS OF APPLIED BIOLOGY, Issue 2 2006A. Gökçe Abstract The contact toxicities of methanol extracts from the nine plant species Hedera helix, Artemisia vulgaris, Xanthium strumarium, Humulus lupulus, Sambucus nigra, Chenopodium album, Salvia officinalis, Lolium temulentum and Verbascum songaricum were tested on the developmental stages of Colorado potato beetle (CPB) (Leptinotarsa decemlineata). About 2 mL of plant extract, 40% (w/w), was applied to the first instar to fourth instar larvae and adult beetles using a Potter spray tower. Most of the tested plant extracts caused relatively low mortality in all the beetle instars. Among the plant extracts, H. lupulus extract was the most toxic to all stages of the insect, except for the adult beetles. Larval mortality ranged from 40% in the fourth instars to 84% in the third instars. In a second series of experiments, dose,response bioassays using H. lupulus extract produced lethal concentration 50 (LC50) values ranging from 10%, 12%, 17% to 46% (w/w) active ingredient (plant material) for instars 1,4, respectively. This increasing mortality trend, however, did not extend to the adult stage where even the maximum dose of 40% plant material did not provide sufficient mortality to allow estimation of a LC50. These results demonstrated that the extract from H. lupulus has potential as an active ingredient in biological pesticides developed to manage larval instars of the CPB. The potential uses of this plant extract may be in conventional and organic pest management or as part of a mixture of plant extracts or conventional insecticides. Before extracts can be considered as biological control agents, their impact on natural enemies should be assessed. [source] Resistance of insect pests to neonicotinoid insecticides: Current status and future prospects ,ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 4 2005Ralf Nauen Abstract The first neonicotinoid insecticide introduced to the market was imidacloprid in 1991 followed by several others belonging to the same chemical class and with the same mode of action. The development of neonicotinoid insecticides has provided growers with invaluable new tools for managing some of the world's most destructive crop pests, primarily those of the order Hemiptera (aphids, whiteflies, and planthoppers) and Coleoptera (beetles), including species with a long history of resistance to earlier-used products. To date, neonicotinoids have proved relatively resilient to the development of resistance, especially when considering aphids such as Myzus persicae and Phorodon humuli. Although the susceptibility of M. persicae may vary up to 20-fold between populations, this does not appear to compromise the field performance of neonicotinoids. Stronger resistance has been confirmed in some populations of the whitefly, Bemisia tabaci, and the Colorado potato beetle, Leptinotarsa decemlineata. Resistance in B- and Q-type B. tabaci appears to be linked to enhanced oxidative detoxification of neonicotinoids due to overexpression of monooxygenases. No evidence for target-site resistance has been found in whiteflies, whereas the possibility of target-site resistance in L. decemlineata is being investigated further. Strategies to combat neonicotinoid resistance must take account of the cross-resistance characteristics of these mechanisms, the ecology of target pests on different host plants, and the implications of increasing diversification of the neonicotinoid market due to a continuing introduction of new molecules. Arch. Insect Biochem. Physiol. 58:200,215, 2005. © 2005 Wiley-Liss, Inc. [source] Genetic analysis of larval survival and larval growth of two populations of Leptinotarsa decemlineata on tomatoENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2001Wenhua Lu Abstract The genetics of adaptation to tomato in Leptinotarsa decemlineata (Say) were investigated in reciprocal F1, F2, and backcross populations generated from crosses between beetles from a tomato adapted population and from a population that was poorly adapted to tomato. Larvae from the parent and test populations were reared on tomato for four days, after which survivorship and larval weights were recorded. Most results indicate that differences in larval growth and survival on tomato between the parent populations are largely determined by autosomal, polygenic mechanisms, the inheritance of which involves a significant dominance component. However, results from F2 crosses are not consistent with this conclusion. A significant difference in larval weights, but not in survival, between reciprocal F1 populations in an analysis of combined data from four separate experiments suggests that maternal cytoplasmic effects may contribute to differences in larval performance on tomato between the adapted and unadapted populations. The unusual results obtained from F2 crosses in this study are not atypical of results from previous studies of the genetics of adaptation to host plants by the Colorado potato beetle. Host plant adaptation by Colorado potato beetles may therefore involve unusual genetic mechanisms that are not easily assessed by classical Mendelian analysis. [source] Compatibility of a natural enemy, Coleomegilla maculata lengi (Col., Coccinellidae) and four insecticides used against the Colorado potato beetle (Col., Chrysomelidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 3 2004É. Lucas Abstract:, ,The toxicity of four insecticides used to control the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), imidacloprid (Admire®), cryolite (Kryocide®), cyromazine (Trigard®), and Bacillus thuringiensis var. tenebrionis (Novodor®), to one of its natural enemies, the 12-spotted lady beetle, Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae) was determined in the laboratory. Toxicity assays against C. maculata adults and larvae consisted of (1) topical applications and (2) exposures to treated foliage and prey, using concentrations up to 10 times the manufacturer's recommendations. Over a 6-day period, cyromazine (insect growth regulator) and B. t. var. tenebrionis (microbial insecticide) had no lethal effects on first and third instars C. maculata. For both larval and adult stages, cryolite (inorganic insecticide) caused very low predator mortality when topically applied and moderate mortality when ingested through contaminated eggs of Colorado potato beetles. Imidacloprid (systemic organic insecticide) was highly toxic to adult and larval C. maculata. Its estimated LD50 at 6 days following treatment, corresponded to 0.02,0.09 times the recommended field concentration, depending on the developmental stage and mode of contamination. These results indicate that integrated pest management programmes for Colorado potato beetles using imidacloprid or, to a lesser degree, cryolite, would be detrimental to C. maculata. Cyromazine and B. t. var. tenebrionis seem to present a better compatibility with the protection of C. maculata populations. [source] Potential of a synthetic aggregation pheromone for integrated pest management of Colorado potato beetleAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2006T. P. Kuhar Abstract 1The relative number of colonizing adult Colorado potato beetles (CPB) Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) coming to pitfall traps baited with the aggregation pheromone (S)-3,7-dimethyl-2-oxo-oct-6-ene-1,3-diol [(S)-CPB I] and the use of the pheromone in a trap crop pest management strategy were evaluated in the field for the first time. 2More than five-fold more adult L. decemlineata were caught in pitfall traps baited with the pheromone compared with controls. However, attraction to the pheromone diminished after 5 days in the field. 3In the trap crop management strategy, more colonizing adults were present in pheromone-treated rows of potatoes compared with untreated middle rows. 4Significantly fewer L. decemlineata egg masses and larvae were found in potato plots that were bordered by pheromone-treated rows, or bordered by imidacloprid + pheromone-treated rows, or rows treated at-planting with imidacloprid compared with untreated (control) potato plots. 5Densities of L. decemlineata egg masses and larvae and percentage defoliation were significantly lower, and marketable tuber yield significantly higher, in conventional imidacloprid-treated potatoes compared with all other treatments. 6Although our results demonstrate the potential for use of the aggregation pheromone in the management of L. decemlineata in the field, more research is needed to optimize the release rates of the attractant and incorporate control methods for cohabiting pests. [source] Plant extract contact toxicities to various developmental stages of Colorado potato beetles (Coleoptera: Chrysomelidae)ANNALS OF APPLIED BIOLOGY, Issue 2 2006A. Gökçe Abstract The contact toxicities of methanol extracts from the nine plant species Hedera helix, Artemisia vulgaris, Xanthium strumarium, Humulus lupulus, Sambucus nigra, Chenopodium album, Salvia officinalis, Lolium temulentum and Verbascum songaricum were tested on the developmental stages of Colorado potato beetle (CPB) (Leptinotarsa decemlineata). About 2 mL of plant extract, 40% (w/w), was applied to the first instar to fourth instar larvae and adult beetles using a Potter spray tower. Most of the tested plant extracts caused relatively low mortality in all the beetle instars. Among the plant extracts, H. lupulus extract was the most toxic to all stages of the insect, except for the adult beetles. Larval mortality ranged from 40% in the fourth instars to 84% in the third instars. In a second series of experiments, dose,response bioassays using H. lupulus extract produced lethal concentration 50 (LC50) values ranging from 10%, 12%, 17% to 46% (w/w) active ingredient (plant material) for instars 1,4, respectively. This increasing mortality trend, however, did not extend to the adult stage where even the maximum dose of 40% plant material did not provide sufficient mortality to allow estimation of a LC50. These results demonstrated that the extract from H. lupulus has potential as an active ingredient in biological pesticides developed to manage larval instars of the CPB. The potential uses of this plant extract may be in conventional and organic pest management or as part of a mixture of plant extracts or conventional insecticides. Before extracts can be considered as biological control agents, their impact on natural enemies should be assessed. [source] | |||||||||||||||||||||||||