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1
Warner, Douglas James. "The potential of carabidae in the control of insect pests of winter oilseed rape." Thesis, University of Hertfordshire, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366035.
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Mason, James Allen Cole. "Flea Beetle Populations and Their Management on Vegetables in Virginia." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/95956.
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Flea beetles (FB), (Coleoptera: Chrysomelidae), are common pests of cabbage and eggplant, but little is known about the FB populations in Virginia, their impact on yield, or the most effective control methods. This research investigates the FB populations and impact of their feeding injury on cabbage and eggplant in Southwest Virginia, and determines the most efficacious control methods.
In Whitethorne, VA, cabbage and eggplant crops were vacuum sampled weekly throughout two summers. Crucifer flea beetle, Phyllotreta cruciferae (Goeze), and striped flea beetle, Phyllotreta striolata Fabr. were found on cabbage; whereas, eggplant flea beetle, Epitrix fucula (Crotch), and the tobacco flea beetle, Epitrix hirtipennis (Melsheimer) were found on eggplant. To evaluate the impact of FB feeding on these plants, insecticides were used to create a range of pest pressure. Flea beetle densities and defoliation was visually assessed weekly and individual plant as well as whole plot yields assessed at harvest. In both crops, as little as 20% defoliation significantly reduced yield, with higher defoliation resulting in lower yield. The efficacy of various insecticides was also evaluated; soil application of the systemic neonicotinoid dinotefuran had the fewest beetles, the least amount of leaf defoliation, and the highest yield in cabbage and eggplant. Lastly, deltamethrin-incorporated mesh row covers were evaluated and shown to provide excellent control of FB compared to an untreated row cover or a control; and comparable to the standard insecticide, dinotefuran. This research helps vegetable growers to better understand the severity of these pests and how to effectively combat them.MSLFS
3
Kalischuk, Andrea Ruth, and University of Lethbridge Faculty of Arts and Science. "Density and efficacy of the flea beetle Aphthona Lacertosa (Rosenhauer), an introduced biocontrol agent for leafy spurge, in Alberta." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2001, 2001. http://hdl.handle.net/10133/119.
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Biocontrol has been critized because the target effects of biocontrol introductions have not been studied rigorously. The objectives of this thesis were 1)to assess quantitatively the efficacy of a classical biocontrol agent after its release and 2)to suggest factors that affect the density and distribution of the biocontrol agent. In 1997, Aphthona lacertosa, a root-feeding flea beetle that is native to Europe, was released for the biological control of leafy spurge in Alberta. The beetles had established at more than 75% of the release sites that were monitored in 1999. In 2000, the peak abundance of A.lacertosa across release sites ranged from low (<10 beetles m-2) to high (>70 beetles m-2). Sites with high beetle densities had a significantly greater local (ie. within 5m of release point) reduction of leafy spurge than sites with low beetle densities. The density and distribution of A. lacertosa are affected by cumulative degree-days (CDD) at the release site and plant lacertosa are affected by cumulative degree-days (CDD) at the release site and plant morphology, respectively. Beetle population growth may be enhanced by releasing A. lacertosa at sites where there are more CDD. It is expected that high densities of A. lacertosa will effectively control leafy spurge populations.93 leaves : ill. (some col.) ; 29 cm.
4
Van, der Westhuizen Liamé. "The evaluation of Phenrica sp.2 (Coleoptera: Chrysomelidae: Alticinae), as a possible biological control agent for Madeira vine, Anredera cordifolia (Ten.) Steenis in South Africa." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1005375.
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Anredera cordifolia (Basellaceae), Madeira vine, is a perennial, semi- succulent climber native from Paraguay to southern Brazil and northern Argentina. It has a history of weediness and difficulty of control once established. In South Africa Madeira vine has a wide range and distribution with altitudes ranging from 10-1800m above sea level. Described as a transformer species, its sheer weight is capable of breaking branches off trees, causing the potential collapse of forest canopies. Chemical and mechanical control methods are expensive, labour intensive and may provide only temporary relief. A biological control programme was therefore initiated in 2003. Cf Phenrica sp. 2 (Coleoptera: Chrysomelidae: Alticinae), was field collected from A. cordifolia in Brazil, SSW of Cascavel in the Paraná Province during a survey in November 2003. Eggs are laid in groups of 16 with the average fertility rate being 89%. After going though three larval instars, the larvae pupate in the soil with the adults eclosing after a period of 17 days. The total developmental time for a generation from egg to egg ranges between 7-8 weeks. Biological traits that favour the flea beetle as a possible biological control agent include long-lived adults (up to 5 months) and multiple generations during the summer period. Both adults and larvae feed extensively on leaves and stems and although developmental rates will slow down during the winter period, no indication of a definite diapause was found under the prevailing laboratory conditions. After completing the larval no-choice trials with twenty-six plant species from 14 plant families Phenrica sp. 2 proved to be adequately host specific, as larval development was only supported by 3 Basellaceae species (including the control A. cordifolia) and one Portulacaceae species. All of these are introduced species in South Africa. The only indigenous Basella species could not be tested as it has a very marginal distribution, and because it’s inconspicuous nature, it is seldom seen or collected. Adult multi-choice trials were restricted to species that could sustain larval development to give some indication of the acceptability of these species for adult feeding and oviposition. Although adult feeding was initially concentrated on B. alba, the oviposition preference was clear-cut as females only oviposited on A. cordifolia. In order to quantify the impact of Phenrica sp. 2 on plant biomass and to assess the incidence and intensity of foliar damage, a pair of adults was confined to the host plant, for 2 generations, with different levels of larval densities. The results indicated that the host plant, due to both larval and adult feeding, suffered leaf losses of up to 55%. Anredera cordifolia was however still capable of enlarging the root mass despite suffering huge leaf losses. This would imply that A. cordifolia has an effective re-growth capacity and it will only be vulnerable to attack of the storage organs that enable re-growth, or to repeated attack of other plant parts through which reserves are exhausted. Unfortunately the period of exposure (24 days) was too short to prove that Phenrica sp. 2 impacts on the below ground dry mass, but should the plant be completely defoliated, as was observed in the field, the host plant would be forced to deplete stored resources. Phenrica sp.2 has shown to be very host specific and although A.cordifoia loses its leaves during the winter period in most provinces in South Africa, the adults are long-lived and should be able to survive the leafless periods. Further more the relatively short life cycle, high fecundity and 3 generations per year should theoretically insure a strong population build-up that would improve the chances of establishment in the field. All indications are that Phenrica sp. 2 is an agent well worth considering for the biological control of A. cordifolia.
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Mkize, Nolwazi. "Insect pests of cultivated and wild olives, and some of their natural enemies, in the Eastern Cape, South Africa." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1005403.
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This thesis has two focuses. The first problem facing the olive industry in the Eastern Cape is the growers’ perceptions of both what the industry will provide them and what a pest management program might entail. The second focus is the biology of olive pests in the Eastern Cape in terms of understanding their populations and their natural enemies on private farms, with future hopes of understanding how Integrated Pest Management strategies can be developed for this crop. Eastern Cape private farmers, small-scale farmers and workers from agricultural training institutions were interviewed regarding the history and cultivation of the local olive crop. Only one commercially viable olive grove was identified; other groves were small, experimental pilot ventures. The introduction of olives to small-scale farmers and agricultural training schools was generally a top-down initiative that led to a lack of sense of ownership and the trees being neglected. Other problems included poor human capital; poor financial capital; lack of adequate support; lack of knowledge transfer and stability; lack of communication and evaluation procedures of the project; miscommunication; and finally, olive pests. Apart from hesitancy to plant at a commercial scale, the main problem facing private farmers (Varnam Farm, Hewlands Farm and Springvale Farm) was pests. Therefore an investigation of pests from private farms was conducted ranging from collection of cultivated and wild olive fruit and flea beetle larvae for parasitism, trapping systems both for fruit flies and olive flea beetle adults. A survey of olive fruits yielded larval fruit flies of the families Tephritidae (Bactrocera oleae (Rossi), B. biguttula (Bezzi) and Ceratitis capitata (Wiedemann)) and Drosophilidae (Drosophila melanogaster (Meigen)) from wild olives (O. europaea cuspidata (Wall. ex G. Don) Cif.) but none from cultivated olives (O. e. europaea L.). Braconid wasps (Opiinae and Braconinae) were reared only from fruits containing B. oleae and B. biguttula. This suggests that B. oleae is not of economic significance in the Eastern Cape, perhaps because it is controlled to a significant level by natural enemies, but B. biguttula may be a potential economic pest. A survey of adult fruit flies using ChamP traps baited with ammonium bicarbonate and spiroketal capsules and Sensus trap baited with methyl eugenol and Questlure confirmed the relative importance of B. biguttula over B. oleae. ChamP traps were over 50 times better than Sensus traps for mass trapping of B. biguttula but both were ineffective for trapping B. oleae and C. capitata. Six indigenous flea beetles of the genus Argopistes Motschulsky (Chrysomelidae: Alticinae) were found, three described by Bryant in 1922 and 1944 and three new species. Their morphology was investigated by scanning electron microscopy and mutivariate morphometric analysis. The leaf-mining larvae are pests of wild and cultivated olives in South Africa and threaten the local olive industry. At Springvale Farm, A. oleae Bryant and A. sexvittatus Bryant preferred the upper parts of trees, near new leaves. Pseudophanomeris inopinatus (Blkb.) (Braconidae) was reared from 23 Argopistes larvae. The beetle larvae might not be controlled to a significant level by natural enemies because the rate of parasitism was low. The olive flea beetles showed no attraction to traps containing various volatile compounds as baits. The lace bug, Plerochila australis Distant (Tingidae), was sometimes a pest. It showed a preference for the underside of leaves on the lower parts of the trees. A moth, Palpita unionalis Hübner (Crambidae), was reared in very low numbers and without parasitoids. A twig-boring beetle larva, chalcidoid parasitoids and seed wasps of the families Eurytomidae, Ormyridae and Eupelmidae were also recorded.
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Zaplachinski, Steven T. "Pulsed-release of flea beetle deterrence proteins in transgenic Brassica napus." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0016/NQ38518.pdf.
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Setter, Cassandra Marie. "Weed Control Effects on Native Species, Soil Seedbank Change, and Biofuel Production." Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29318.
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Aphthona spp. flea beetles were released in the Little Missouri National Grasslands
(LMNG) in western North Dakota in 1999 to control leafy spurge (Euphorbia esula L.). The
changes in soil seed bank composition and leafy spurge density were evaluated on two
ecological sites five (2004) and ten years (2009) after Aphthona spp. release to monitor
the effectiveness of the insects on weed control and associated change in plant
communities. In 2009, leafy spurge stem density averaged 2 and 9 stems m-2 in the loamy
overflow and loamy sites, respectively, compared to 110 and 78 stems m-2, respectively, in
1999 and 7 and 10 stems m-2, respectively, in 2004. Leafy spurge constituted nearly 67%
of the loamy overflow seed bank in 1999 compared to 17% in 2004 and 2% in 2009. In the
loamy seedbank, the weed represented nearly 70% in 1999 compared to approximately
11% in 2004 and 15% in 2009. As leafy spurge was reduced, native species diversity and
seed count increased ten years following Aphthona spp. release. High-seral species
represented 17% of the loamy overflow seedbank in 2009, an increase from 5% in 1999.
However, Kentucky bluegrass, a non-target weedy species, increased over 250% in the
loamy overflow seedbank from 2004 to 2009. The reestablishment of native plant species
has often been slow in areas where leafy spurge was controlled using Aphthona spp. A
bioassay was completed to evaluate native grass establishment when grown in soil from
Aphthona spp. release and non-release sites throughout North Dakota. Native grass
production was not affected when grown in soil collected from established Aphthona spp. sites (1.5 g per pot) compared to soil without insects (1.6 g per pot). The cause of reduced
native grass production in sites with Aphthono spp. previously observed is unknown but
may have been due to a chemical inhibition caused by the insects within the soil that no
longer exists. The native warm-season switchgrass (Ponicum virgotum L.) may be an
alternative to corn for efficient biofuel production; however, control of cool-season grassy
weeds has been a problem in switchgrass production. Various herbicides were evaluated
for smooth bromegrass (Bromus inermis Leyss.) and quackgrass [Elymus repens (L.) Gould]
control in an established switchgrass stand near Streeter, ND and a weed-infested field in
Fargo, ND. Switchgrass yield was higher than the control 14 mo after treatment (MAT)
when aminocyclopyrachlor or sulfometuron were applied early in the growing season, but
no treatment provided satisfactory long-term grassy weed control. Herbicides were
reevaluated at increased rates for smooth bromegrass or quackgrass control in Fargo.
Sulfometuron provided 99% smooth bromegrass control when applied at 280 g ha-1 in the
fall but injured other grass and forb species as well. Sulfometuron would likely be
injurious to switchgrass and could not be used for biofuel production.
Aminocyclopyrachlor did not injure other grass species but only reduced smooth
bromegrass control by 76% when applied at 280 g ha-1 in the fall. No treatment provided
satisfactory long-term quackgrass control.
8
Koritsas, Vasile Michael. "Interactions between oilseed rape (Brassica napus L.) and cabbage stem flea beetle Psylliodes chrysocephala (L.)." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46397.
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Kalischuk, Andrea Ruth. "Density and efficacy of the flea beetle Aphthona lacertosa (Rosenhauer), an introduced biocontrol agent for leafy spurge, in Alberta." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq61042.pdf.
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Mponda, O. K. K. "Involving farmers in the design of low-input control programme for sesame flea beetle (Alocypha bimaculata, Jacoby) in S.E. Tanzania." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320951.
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Kerns, David L. "Common Insect Contaminants Found in Arizona Lettuce." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2000. http://hdl.handle.net/10150/144795.
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2 pp.This publication describes the common insects found in Arizona lettuce through the use of pictures. The insects include; lepidopterous larva, striped flea beetle, leafminer fly, leafminer mine, adult western flower thrips, winged adult aphid, false chinch bug, lygus bug, potato leafhopper, and threecornered alfalfa hopper.
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Simelane, David Okhi. "Prediction of safety and effectiveness of a candidate biocontrol agent : quarantine evaluation of the root-feeding, Mexican flea beetle, Longitarsus bethae, for potential release against the noxious weed, Lantana camara, in Africa." Doctoral thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/6190.
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Includes bibliographical references (leaves 151-173).A root-feeding, Mexican flea beetle, Longitarsus bethae Savini & Escalona 2005 (Coleoptera: Chrysomelidae: Alticinae), was evaluated in quarantine as a candidate biological control agent for the noxious weed, Lantana camara L. (Verbenaceae). The premise was that L. bethae would only be released if it could be ascertained that it was: (i) safe for non-target plants; (ii) likely to inflict significant damage on the target weed; and (ii) capable of surviving under the various (abiotic and biotic) environmental conditions in its new range.
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Irwin, Caleigh. "Phenology of Crucifer and Striped Flea Beetles, and Potential of the Anthranilic Diamide Insecticide, Cyantraniliprole, as a Canola Seed Treatment for Control of Flea Beetles." Thesis, 2011. http://hdl.handle.net/10214/3021.
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This research investigated the phenology of the striped flea beetle (Phyllotreta striolata (Fabricius) (SFB) and crucifer flea beetle (Phyllotreta cruciferae (Goeze)) (CFB), and examined the efficacy and the persistence of biological activity of the reduced-risk insecticides cyantraniliprole, clothianidin, and thiamethoxam applied as seed treatments to spring canola.
Yellow sticky cards were placed around field perimeters in order to assess if CFB and SFB have synchronous phenology. It was found that CFB and SFB have largely asynchronous populations in southern Ontario. In laboratory bioassays, while flea beetle control with cyantraniliprole was comparable to that provided by thiamethoxam or clothianidin at the cotyledon stage, control did not persist through the 1st and 2nd leaf stages. Thiamethoxam and clothianidin both provided moderate control of flea beetles in both 1st and 2nd leaves. Field studies suggested that cyantraniliprole may offer control of flea beetles comparable to that provided by thiamethoxam and clothianidin.E.I. DuPont Canada Co.
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Potter, KJB. "Factors affecting establishment and efficacy of the ragwort flea beetle, Longitarsus flavicornis (Stephens), in the biological control of ragwort, Senecio jacobaea L., in Tasmania." Thesis, 2003. https://eprints.utas.edu.au/21256/1/whole_PotterKarinaJaneBowen2003_thesis.pdf.
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"Effect of TRANSPARENT TESTA GLABRA1 on trichome development, growth, and insect resistance in a Brassica napus AtGLABRA3+ background." Thesis, 2012. http://hdl.handle.net/10388/ETD-2012-12-847.
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Glabrous Brassica napus cv Westar and very hairy AtGL3+ B. napus were transformed using Agrobacterium tumefaciens and either a full length trichome regulatory gene BnTTG1 (isoform 1 coding region called O-TTG1) or an RNAi cassette with 260 bp of a conserved region between isoform I and II (called K-TTG1), each driven by the CaMV 35S promoter. Agronomic and trichome phenotypes were observed in the resulting lines. Transformed lines developed in the glabrous Westar background showed no changes in growth or trichome density and transformation efficiency was similar to that of an empty vector control construct. Over-expression of BnTTG1 in the AtGL3+ B. napus background resulted in low transformant survival and poor seed viability, with the only surviving line O-3-7 being taller than non-transformed lines and with a completely glabrous phenotype. The two knock-down lines with the lowest BnTTG1 expression showed a dramatic increase in trichome density, with longer trichomes and expanded trichome density (up to the 12th leaf in the K-5-8 line) compared to the AtGL3+ hairy background line, which showed increased trichome density only on the first three leaves. Moreover, K-5-8 plants were healthy, with both vegetative and reproductive growth similar to that of Westar non-transgenic control plants under both greenhouse and field conditions. The relative expression of five B. napus primary trichome regulatory genes and AtGL3 was measured in three different tissues of B. napus Westar, and the AtGL3+, K-5-8 and O-3-7 transgenic lines. Over-expression of AtGL3 resulted in changes in the expression of BnGL3, BnGL2 and BnTRY. Manipulation of BnTTG1 levels also resulted in changes in expression of these three genes in addition to AtGL3. AtGL3+ plants and O-3-7 also showed increased red pigment accumulation in several above ground vegetative tissues including cotyledons, hypocotyl and leaves, whereas the K-5-8 line (knock down of TTG1) had less anthocyanin in the same tissues. The level of anthocyanin accumulation corresponded to the relative expression of the three primary anthocyanin regulatory genes BnDFR, BnANS and BnGST. In a laboratory bioassay, diamondback moth (DBM) adults (Plutella xylostella) laid more eggs on hairy leaves of K-5-8 than glabrous Westar. However, more feeding damage from young DBM larvae was observed on Westar leaves than K-5-8 in both choice and no-choice feeding assays. In a field test comparing Phyllotreta flea beetle feeding, the hairy K-5-8 leaves showed between a 30-50% reduction in feeding over four ratings on 14 to 28 day old seedlings. Curiously, the glabrous cotyledons of the two hairy lines (AtGL3+ and K-5-8) proved to be more resistant than wild type B. napus Westar cotyledons from Helix XTra® insecticide-treated or non-treated seed. These data support the introduction of AtGL3 and the knockdown of BnTTG1 to induce a dense trichome phenotype, into otherwise glabrous B. napus, resulting in an increased host plant resistance to crucifer insects, without agronomic penalties.
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Andersen, Caryn L. "The life history and management of Phyllotreta cruciferae and Phyllotreta striolata (Coleoptera: Chrysomelidae), pests of brassicas in the northeastern United States." 2004. https://scholarworks.umass.edu/theses/3091.
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Van, der Westhuizen Liamé. "The evaluation of Phenrica sp. 2 (Coleoptera: Chrysomelidae: Alticinae), as a possible biological control agent for Madeira vine, Anredera cordifolia (Ten.) Steenis in South Africa /." 2006. http://eprints.ru.ac.za/496/.
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Mkize, Nolwazi. "Insect pests of cultivated and wild olives, and some of their natural enemies, in the Eastern Cape, South Africa /." 2008. http://eprints.ru.ac.za/1613/.
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Damaška, Albert. "Evoluce, biogeografie a systematika mechových dřepčíků (Coleoptera: Chrysomelidae: Galerucinae)." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-405954.
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Flea beetles (Alticini) are a highly diversified group of leaf beetles (Chrysomelidae) with about 8 000 known species from about 560 genera distributed worldwide except Antarctica. The major life strategy of flea beetles is external feeding on vascular plants, similarly to other leaf beetles. However, studies published during last years revealed existence of numerous different flea beetle genera feeding on mosses. Moss-inhabiting flea beetles are usually highly specialized and share similar morphological characteristics, including flightlessness, compact body shape and modified antennae. However, their phylogenetic position remained unknown. In this study, I performed a phylogenetic analysis of 14 known moss- and leaf litter inhabiting flea beetle genera, included into a large dataset of various genera of flea beetles. I sequenced 2 mitochondrial and 2 nuclear genes previously used for phylogenetic analyses of Alticini. I also added numerous Neotropical external feeding alticine genera, because taxon samples from previous studies (Ge et al. 2012; Nie et al. 2017) consisted mainly of Oriental genera. Although deep divergences and phylogenetic positions of several genera were not resolved, the analysis revealed a multiple origin of moss- and leaf litter inhabitance among flea beetles. The morphologically...
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Pernal, Stephen Francis. "Economic injury levels and feeding studies for the potato flea beetle, Epitrix cucumeris (Harris), in Manitoba." 1992. http://hdl.handle.net/1993/7225.
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In 1989 and 1990, cv. Russet Burbank potato plants were grown in cages in field plots, and densities of potato flea beetles, Epitrix cucumeris (Harris), and Colorado potato beetles, Leptinotarsa decemlineata (Say), were introduced in different multiples of naturally occurring field densities. Colorado potato beetles were introduced only in the early part of the growing season, but potato flea beetles were introduced for the duration of the season. Numbers of feeding punctures per leaflet were counted in the lower, middle, upper and upper non-terminal strata of plants. The yield of tubers was weighed, graded and examined for common scab, Streptomyces scabies (Thaxter). Without early season injury by Colorado potato beetle, plant had no yield loss up to 290 flea beetles per plant; above this density, yield was inversely proportional to flea beetle density. The level of economic damage for these plants ranged between 0.43-1.87%, equivalent to a peak density of 300-335 flea beetles per plant. For plants which had sustained early season Colorado potato beetle injury, yield loss was linear and inversely proportional to flea beetle density over the entire response. For these plants, the level of economic damage ranged between 0.40-1.88%, equivalent to a peak density of only 4-19 potato flea beetles per plant. Behavioral models were used to describe the spatial and temporal switching pattern of flea beetle feeding. Beetles changed their preferred site of feeding from lower parts of the plant to upper regions as the growing season progressed. High densities of flea beetles had an inhibitory effect on the amount of defoliation caused per individual, and this may alter the pattern of feeding preference by causing beetles to disperse more evenly throughout the plant. A population model was also derived which established a relationship between feeding punctures per leaflet and average potato flea beetle weeks. This relationship enables the estimation of flea beetle numbers per plant, but is very sensitive to the accuracy of feeding puncture counts. Very few tubers exhibited signs of common scab disease, but there was a positive correlation between number of feeding punctures and numbers of immature potato flea beetles. The absence of scab disease suggests that its incidence is less affected by flea beetle densities, than by abiotic factors such as soil moisture, and varietal differences in susceptibility. A preliminary examination of feeding by Melanoplus bivittatus (Say) and Melanoplus sanguinipes (Fabricius) on potato plants showed no significant yield response to occur at varying densities of these species.
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Chen, Wei-Chen, and 陳韋辰. "The effects of exogenous methyl jasmonate application induced defense responses in radish and its effects on flea beetle, Phyllotreta striolata." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/29102909714770048863.
Full textAbstract:
碩士國立中興大學
昆蟲學系所
100
When plants injured by attacker, they would use some strategies to reduce the damage caused by herbivory, and these reactions are diversification; but chemical defense compound maybe the main way. One key compound to controlling of production of chemical defense compound is jasmonic acid (JA). The jasmonic acid is a plant hormone which regulates plant’s induced resistance. Previous studies pointed out that exogenous methyl jasmonate (MeJA) can induce plant defense response. In addition, some studies indicated that applying jasmine acid in different parts of plant can induce different types of chemical defense compound. In this study, applying methyl jasmonate at different parts of radish plants to explore the effects on plant induced resistance and to find the influence on the flea beetle (Phyllotreta striolata) adult feeding performance and larva survival. The treatment included applying the 1.5 mM methyl jasmonate solution on above-ground, below-ground, both above- and below-ground, and control group. Chemical analysis of the leaf on 0, 1st, 3rd, 5th, 7th days and 10th day after applying methyl jasmonate and included trypsin inhibitor (TI), polyphenol oxidase (PPO), nitrogen content, and sinigrin. In addition, the treated plant was used to test effects on flea beetle adults feeding and larva survival rate. The results showed that the flea beetle feeding area decreased significantly on 3rd, 5th, 7th days and 10th day. Survival rate of larva significantly decline in the above and below-ground treatment. The below-ground treatment reveals the delayed eclosion compared to above-ground treatment. In addition, the results also showed that methyl jasmonate can induce trypsin inhibitor (TI) and sinigrin significantly; but have no effect on different plant parts. In summary, the results indicate that exogenous methyl jasmonate on radish can change the chemical defense compound, and affect flea beetle growth performance.
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Huang, Yu-Jen, and 黃育仁. "Studies on infection of the striped flea beetle, Phyllotreta striolata (Fabricius), with the entomopathogenic nematode, Steinernema abbasi and the white muscardine fungus, Beauveria bassiana." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/34438960854945370042.
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碩士國立中興大學
昆蟲學系
91
Studies on infection of the striped flea beetle, Phyllotreta striolata (Fabricius), with the entomopathogenic nematode, Steinernema abbasi and the white muscardine fungus, Beauveria bassiana YU-Jen Huang ABSTRACT The striped flea beetle, Phyllotreta striolata, was reared massively with the potted radish plants in cage in the greenhouse. The highest adult emergence per cage and average female fertility were 1,086.7± 109.9 and 12.8 ± 1.3, respectively. The rearing method for keeping culture of P. striolata in the greenhouse can provide a constant population for bioassays. Pathogenicity of the entomopathogenic nematode, Steinernema abbasi, to the soil-inhabit developmental stages (larva, prepupa, and pupa) of P. striolata and infection of P. striolata with the white muscardine fungus, Beauveria bassiana, was studied in the greenhouse and laboratory. The LC50 values of various instars were determined by using petri dish assay method. The value of LC50 decreased with larval growth for nematode treated groups. The LT50 values of 3rd-instar larvae were significantly lower than those of 2nd-instar with higher inoculation (20 IJs /0.1 ml). The effect of temperature on pathogenicity of S. abbasi to P. striolata was tested by inoculating all immature stages with different nematode concentrations (5, 10, 15 and 20 IJs/0.1 ml) at temperatures 21, 25, and 30℃. S. abbasi was more virulent at 25 and 30℃ than at 21℃. LT50 and LC50 values of various instars were decreased with increasing temperatures for nematode treated groups. The potted test was conducted with three concentrations of S. abbasi to control P. striolata in greenhouse. The higher applied concentrations (25, 51 and 102 IJs/cm2) of S. abbasi had better control as compared with 6 IJs/cm2, and the mortalities were higher than 90%. An insecticide, cartap, commonly used in radish field was evaluated with five concentrations (1.2-12,000 g/ml) for their inhibition on survival of S. abbasi by dipping test. The nematodes were adversely affected by those concentrations showing abnormal behavior with a curled or coiled posture, and the survival rates declined with increasing of both the concentrations and exposing time. Pathogenicity of the white muscardine fungus, B. bassiana, isolated from four insect hosts to P. striolata was studied. The susceptibility of adult beetles was highest with the isolate from Odoiporus longicollis Oliv. (B.b-O) (LC50=6.11 × 106 conidia/ml), followed by the isolates from Cerambycidae (B.b-C) and Bombyx mori L. (B.b-B), but lowest by that from Labiduridae (B.b-L) (LC50=2.71 × 107 conidia/ml). The LT50 values of 4 isolates were shortened as the concentrations of conidial suspension increased. The insecticides, 43﹪profenofos (1,000X) and 50﹪cartap (1,000X), could inhibit mycelial growth of B. bassiana. Therefore, B. bassiana should not be applied by mixing with profenofos or cartap in the filed.