No description available.

Yield losses from infestations of root maggots (Delia spp.) (Diptera: Anthomyiidae) can be severe in canola crops in central Alberta. Studies were undertaken in central Alberta, Canada to manipulate agronomic practices that have potential to affect crop yield, root maggot infestations, and the survival and abundance of Aleochara bilineata (Coleoptera: Staphylinidae), which is an important natural enemy of root maggots. I investigated tillage regime (conventional versus zero tillage), row spacing, and seeding rate to assess effects on Delia spp. and A. bilineata populations. In general I observed greater root maggot incidence and damage, and greater activity density of A. bilineata, in plots subjected to a conventional tillage regime than in a zero tillage regime. I found relatively greater parasitism of root maggot puparia by A. bilineata in plots subjected to a zero tillage regime than a conventional tillage regime. No consistent effects were observed on A. bilineata activity in relation to seeding rate and row spacing. In this study, there is no evidence to conclude that tillage regime had a significant effect on canola seed yield. Seed yields in relation to seeding rate and row spacing were variable. In the context of integrated pest management in canola cropping systems, I suggest that canola growers utilize zero tillage in conjunction with adopting the currently recommended seeding rates of between 5.6 to 9.0 kg per ha and row spacing of 30 cm because this can bring advantages in terms of improved management of root maggots and other important canola pests like flea beetles and weeds. / Plant Science

No description available.

Arthropod natural enemies play a key role in controlling potentially damaging pest populations in agroecosystems. An abundant and diverse natural enemy community is associated with higher yields in a variety of crops. Certain aspects of soybean production can make a field more or less amenable to a robust natural enemy community. For instance, commonly used broad-spectrum insecticides which are highly toxic to most arthropods can decrease natural enemy densities and allow for secondary pest outbreaks. Selective insecticides that have less impact on natural enemy populations allow for pest control while preserving important predators. Another production decision that could alter natural enemy communities is the choice of cropping system, specifically planting early (full season) or late, after small grain harvest (double crop). My research objectives were to examine how 1) selective insecticides and 2) cropping system affect the density and diversity of natural enemies in Virginia soybean. To address the first objective I compared the natural enemy community in soybean plots that were exposed to selective insecticides, broad-spectrum insecticides or no insecticide. I sampled insects using three different techniques and found that the two selective insecticides I tested, both from a new class called diamides, did not reduce the natural enemy community compared to controls. To examine how cropping system affects the natural enemy community I sampled full season and double crop fields during the growing season for two years. In 2014 ground-dwelling spider diversity was higher in full season soybean. In both years, double crop soybeans had higher abundance of spiders and insect natural enemies on the ground and in the foliage compared with full season soybean. This was unexpected, since double crop soybeans are planted later than full season and arthropod populations would have less time to colonize and grow. When I compared diversity of a family of predatory beetles I found higher diversity in full season soybean. The similarity in spider and insect natural enemy diversity and abundance trends suggests that a greater number of species can co-exist in full season soybean, while in double crop soybeans a few dominant natural enemies thrive. / Ph. D.

Diss. (sammanfattning) Umeå : Umeå universitet, 2007. / Härtill 4 uppsatser.

Submitted by Matheus Alves de Siqueira (matheuspucc2012@gmail.com) on 2018-10-10T15:23:38Z No. of bitstreams: 1 Dissertação Mestrado - Final.pdf: 1507669 bytes, checksum: 9b8cf5a5eebde96d5328c987222e1bd9 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-10-10T17:40:27Z (GMT) No. of bitstreams: 1 siqueira_ma_me_jabo.pdf: 1507669 bytes, checksum: 9b8cf5a5eebde96d5328c987222e1bd9 (MD5) / Made available in DSpace on 2018-10-10T17:40:27Z (GMT). No. of bitstreams: 1 siqueira_ma_me_jabo.pdf: 1507669 bytes, checksum: 9b8cf5a5eebde96d5328c987222e1bd9 (MD5) Previous issue date: 2018-08-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / RESUMO – A família Pseudococcidae é a segunda maior da Infraordem Coccomorpha, com cerca de 2000 espécies descritas. No Brasil, conhecidas popularmente como cochonilhas-farinhentas, compreendem a terceira maior família, com 77 espécies registradas, distribuídas em 22 gêneros. Destas, 32 espécies são conhecidas para o estado de São Paulo, sendo 30% polífagas e de origem exótica, infestando plantas de importância agrícola. O controle biológico é uma alternativa, e dentre os inimigos naturais os himenópteros parasitoides vêm sendo muito utilizados. O objetivo deste trabalho foi inventariar os micro-himenópteros parasitoides de 11 espécies de pseudococcídeos pragas, primarias ou secundarias, de várias culturas e plantas ornamentais no estado de São Paulo, como café, citros, pinha, goiabeira, entre outros, relacionando estes com seu hospedeiro, origem e distribuição geográfica. Os levantamentos dos himenópteros parasitoides foram realizados entre agosto de 2016 e agosto de 2017, de forma aleatória, em áreas rural e urbana de cinco municípios do estado São Paulo: Jales, Ribeirão Preto, Jaboticabal, São Carlos e Campinas. As espécies de pseudococcídeos amostrados para obtenção dos parasitoides foram: Dysmicoccus brevipes (Cockerell, 1893), Ferrisia virgata (Cockerell, 1893), Leptococcus capixaba Kondo, 2005, Leptococcus minutus (Hempel, 1932), Maconelicoccus hirsutus (Green, 1908), Nipaecoccus nipae (Maskell, 1893), Phenacoccus solenopsis Tinsley, 1898, Planococcus citri (Risso, 1813), Planococcus minor (Maskell, 1897), Pseudococcus cryptus (Hempel, 1918) e Pseudococcus longispinus (Targioni Tozzetti, 1867). Obtiveram-se 628 exemplares de himenópteros parasitoides, distribuídos em 27 espécies. Registra-se aqui, pela primeira vez, Bothriocraera bicolor Compere & Zinna, 1955, Gyranusoidea deionae Noyes, 2000 e Allotropa merrilli Muesebeck, 1954 no Brasil; e, Anagyrus fusciventris (Girault, 1915), Gyranusoidea pseudococci (Bréthes, 1924) e Tetracnemoidea peregrina (Compere, 1939) para o estado de São Paulo; e 26 novas associações entre cochonilha/parasitoide. Os gêneros que apresentaram o maior número de espécies associadas aos pseudococcídeos foram: Gyranusoidea, Anagyrus e Aprostocetus. / ABSTRACT– The Pseudococcidae family is the second largest from the Coccomorpha Infraorder, with about 2000 described species. In Brazil, popularly known as mealybugs, it comprised the third largest family, with 77 species registered, distributed in 22 genera. From these, 32 species are known to the state of São Paulo, being 30% polyphagous from exotic origin, infesting plants of agricultural importance. Biological control is an alternative and among natural enemies, parasitoid Hymenoptera are being widely used. The objective of this work was to inventory the parasitoid microhymenoptera from 11 mealybug pest species, primary or secondary, from various crops and ornamental plants in the state of São Paulo, such as coffee, citrus, sugar-apple, guavas and others, relating these to their host, origin and geographical distribution. The parasitoid hymenopteran surveys were carried out between August 2016 and August 2017, in a random way, in rural and urban areas from five municipalities in the state of São Paulo: Jales, Ribeirão Preto, Jaboticabal, São Carlos and Campinas. The Pseudococcidae species sampled to obtain parasitoids were: Dysmicoccus brevipes (Cockerell, 1893), Ferrisia virgata (Cockerell, 1893), Leptococcus capixaba Kondo, 2005, Leptococcus minutus (Hempel, 1932), Maconelicoccus hirsutus (Green, 1908), Nipaecoccus nipae (Maskell, 1893), Phenacoccus solenopsis Tinsley, 1898, Planococcus citri (Risso, 1813), Planococcus minor (Maskell, 1897), Pseudococcus cryptus (Hempel, 1918) and Pseudococcus longispinus (Targioni Tozzetti, 1867). There were 628 specimens of parasitoid Hymenoptera distributed in 27 different species. It is recorded here, for the first time, Bothriocraera bicolor Compere & Zinna, 1955, Gyranusoidea deionae Noyes, 2000 and Allotropa merrilli Muesebeck, 1954 for Brazil; and, Anagyrus fusciventris (Girault, 1915), Gyranusoidea pseudococci (Bréthes, 1924), e Tetracnemoidea peregrina (Compere, 1939) for the state of São Paulo; and 26 new associations between mealybugs x parasitoids. The genera that presented the greatest number of species associated to the Pseudococcidae were: Gyranusoidea, Anagyrus e Aprostocetus. / 134767/2016-0

<p>The primary goal of this research study was to provide updated pest management recommendations to growers, including the reduction of insecticide applications on a calendar basis by the use of pest economic thresholds, with the purpose of maximizing insecticide efficacy while minimizing the associated negative impacts on natural enemies and their ecosystem services. </p> <p>Commercial watermelon (<i>Citrullus lanatus</i>) production in the Midwest typically relies on neonicotinoid and pyrethroid insecticides to manage insect pests, particularly striped and spotted cucumber beetles (<i>Acalymma vittatum </i>Fabricius and <i>Diabrotica undecimpunctata</i> <i>howardi</i> Barber, respectively). The role of arthropod predators in managing cucumber beetles is not well documented, and data on the effects of insecticides on predators in watermelon production are deficient. Common cucumber beetle predators include coccinellid beetles found on plants, ground-dwelling carabid beetles (Coleoptera: Carabidae) and spiders in several families that inhabit the soil surface in watermelon fields. I hypothesize that these generalist predators and the ecosystem services (e.g., pest predation) they provide are at risk from insecticides used for pest management without regard to economic thresholds. My study compared the effect of insecticide use on cucumber beetle pests, spider predators, collembola populations and field pest predation under two treatments: 1) watermelons treated with neonicotinoid soil drench and subsequent pyrethroid sprays, surrounded by corn with neonicotinoid-treated seeds (Conventional), and 2) watermelons treated only with pyrethroid spray when economic thresholds were reached, surrounded by corn with untreated seeds (IPM).</p> <p>The frequent application of insecticides decreased cucumber beetles in the watermelon plots managed with Conventional pest management; however, they also reduced spider predators, collembola densities, and field pests predation measurements, possibly due to the subsequent pyrethroids applications during the growing season. In addition, our study showed that neonicotinoid seed treatment in corn had no negative impact on any of the above-mentioned response variables measured. </p> <p>Ultimately, following an IPM strategy and the use of pest monitoring helped to reduce unnecessary insecticides applications, conservation of pest regulatory services provided by natural enemies, and possibly less ecological impact to manage significant insect pests in watermelon plots. <b><br> </b></p>

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21165号 / 農博第2291号 / 新制||農||1060(附属図書館) / 学位論文||H30||N5139(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 縄田 栄治, 教授 舟川 晋也, 教授 松浦 健二 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

Resistance development and possible non–target effects have been of concern since the first deployment of genetically modified crops with insecticidal properties. It is especially at the third trophic level and with important predators such as lacewings (Chrysoperla spp.) (Neuroptera: Chrysopidae) where negative effects of Cry 1Ab protein could have adverse effects in agro–ecosystems. Monitoring of the effect of genetically modified Bt maize on non–target organisms is required by law in South–Africa. Neuroptera are excellent indicators of environmental and habitat transformation, and also include key species for signifying areas and faunas that require priority protection. Monitoring techniques, especially for insect eggs, are often labour intensive and time consuming. A study was conducted to determine the preferred oviposition site of Chrysoperla spp. on maize plants to facilitate time–effective searching for eggs of these beneficial insects. Furthermore we determined if the presence of aphids on plants influenced Chrysoperla spp. oviposition preference. Another study was conducted to evaluate the effect of indirect exposure of C. pudica to Cry 1Ab protein, through healthy Bt–maize feeding prey, on its biology. Daily flight activity patterns and the height at which chrysopid adults fly above the crop canopy were also determined, as well as the movement of adult Chrysoperla spp. between maize fields and adjacent headlands. A clear spatial oviposition pattern was observed on maize plants and oviposition was not random as reported in earlier studies. This data facilitates rapid monitoring of the presence of eggs in maize cropping systems and is also of use in general pest management. Choicetest data showed that females responded positively to host plants that were infested with aphids. Feeding studies in which C. pudica larvae were indirectly exposed to Bt–toxin at the 3rd trophic level, showed a limited effect of Bt–toxin on only a few of the parameters that were evaluated. The pupal period and percentage adult emergence of larvae exposed to an unusually high amount of Bt–toxin was significantly shorter and lower respectively than that of the control group. The overall result of this study, in which the possible effect of food quality (prey) was excluded, showed that Cry 1Ab protein had an adverse affect only on certain fitness components during the life cycle of C. pudica. However, since this study represented a worst–case scenario where diverse prey was not available to C. pudica, negligible effects is expected under field conditions where prey is more diverse. It was determined that chrysopids was most active between 16:00 – 23:00 and that they fly largely between 0.5 m – 2.5 m above ground level. An attempt was also made to quantify migration between different vegetations types. This part was terminated because of bad weather conditions at several occasions when the experiment was attempted. Chrysopids were never present in grassland vegetation, but an adjacent lucerne field maintained a large population. As the maize crop developed chrysopid population numbers increased inside the field, presumably originating from the lucerne field. / Thesis (M.Sc (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

Resistance development and possible non–target effects have been of concern since the first deployment of genetically modified crops with insecticidal properties. It is especially at the third trophic level and with important predators such as lacewings (Chrysoperla spp.) (Neuroptera: Chrysopidae) where negative effects of Cry 1Ab protein could have adverse effects in agro–ecosystems. Monitoring of the effect of genetically modified Bt maize on non–target organisms is required by law in South–Africa. Neuroptera are excellent indicators of environmental and habitat transformation, and also include key species for signifying areas and faunas that require priority protection. Monitoring techniques, especially for insect eggs, are often labour intensive and time consuming. A study was conducted to determine the preferred oviposition site of Chrysoperla spp. on maize plants to facilitate time–effective searching for eggs of these beneficial insects. Furthermore we determined if the presence of aphids on plants influenced Chrysoperla spp. oviposition preference. Another study was conducted to evaluate the effect of indirect exposure of C. pudica to Cry 1Ab protein, through healthy Bt–maize feeding prey, on its biology. Daily flight activity patterns and the height at which chrysopid adults fly above the crop canopy were also determined, as well as the movement of adult Chrysoperla spp. between maize fields and adjacent headlands. A clear spatial oviposition pattern was observed on maize plants and oviposition was not random as reported in earlier studies. This data facilitates rapid monitoring of the presence of eggs in maize cropping systems and is also of use in general pest management. Choicetest data showed that females responded positively to host plants that were infested with aphids. Feeding studies in which C. pudica larvae were indirectly exposed to Bt–toxin at the 3rd trophic level, showed a limited effect of Bt–toxin on only a few of the parameters that were evaluated. The pupal period and percentage adult emergence of larvae exposed to an unusually high amount of Bt–toxin was significantly shorter and lower respectively than that of the control group. The overall result of this study, in which the possible effect of food quality (prey) was excluded, showed that Cry 1Ab protein had an adverse affect only on certain fitness components during the life cycle of C. pudica. However, since this study represented a worst–case scenario where diverse prey was not available to C. pudica, negligible effects is expected under field conditions where prey is more diverse. It was determined that chrysopids was most active between 16:00 – 23:00 and that they fly largely between 0.5 m – 2.5 m above ground level. An attempt was also made to quantify migration between different vegetations types. This part was terminated because of bad weather conditions at several occasions when the experiment was attempted. Chrysopids were never present in grassland vegetation, but an adjacent lucerne field maintained a large population. As the maize crop developed chrysopid population numbers increased inside the field, presumably originating from the lucerne field. / Thesis (M.Sc (Environmental Science))--North-West University, Potchefstroom Campus, 2011.