Mealybugs (Order Hemiptera: Superfamily Coccoidea) represent a persistent problem in grape-growing regions globally, with a notable increase in infestations in recent times. The current study investigates the species composition and seasonal dynamics of mealybugs in vineyards. Pseudococcus maritimus and Ferissia gilli remain the dominant species, while Pseudococcus viburni was also spotted during two separate instances and Planococcus ficus remained absent. Commercially available pheromone delta traps and adhesive bands were deployed to capture the male mealybugs, while numerically higher efficacy was observed in the adhesive band trap. Notably, the placement of adhesive band traps on the cordon and trunk revealed differential male mealybug captures, probably indicating their movement within the vines. The research also divulges into the life cycle of mealybugs and their population densities during the sampling season. The main highlight has been the lower population density of earlier nymphal stages of the first generation of mealybugs followed by the colonization of grapevines by the second-generation crawlers. Adults of second generations give rise to the overwintering stages of mealybugs. Traditionally the research also explores the species and seasonal population dynamics of ants along with mealybugs and their management in Virginia vineyards. The activity of fifteen genera of ants in the vineyard was recorded, with some of the dominant ant genera like Tetramorium, Crematogaster, and Lasius were recorded in the vineyard actively tending and defending the mealybugs and moving them around. Fruit cluster infestation was also higher in the control treatment in comparison to sugar dispenser and ant bait dispenser treatments. This comprehensive assessment of ant diversity further deepens our understanding of the intricate ecosystem within vineyards. A spray trial using three different insecticides with distinct modes of action (Buprofezin, Bifenthrin, and Spirotetramat) in two of the commercial vineyards. Preliminary results indicate that on some days after treatment, insecticides effectively controlled mealybug populations, offering a glimmer of hope to vineyard owners grappling with infestations. Mealybugs pose a significant threat to grape cultivation, and this research provides valuable insights that can help vineyard owners and grape growers develop more targeted and effective control strategies. Species identification, understanding their behavior, and exploring potential allies in the fight against mealybugs are all crucial steps toward maintaining the health and productivity of vineyards in Virginia. While challenges remain in the battle against mealybugs, this research marks a significant step forward in safeguarding grape cultivation in Virginia and potentially reshaping strategies for controlling these persistent pests in vineyards. Growers and researchers alike eagerly await further developments and the practical application of these findings to protect the flourishing vineyards of the region. / Doctor of Philosophy / Mealybugs are common grapevine pests, recently causing a nuisance in vineyards across the United States and Canada. Some of the previously documented species of mealybugs common in the eastern part of the States include grape mealybug, obscure mealybug, Gill's mealybug, and long-tailed mealybugs. The research has mainly addressed the mealybugs and their tending ant species and their management in vineyards in Virginia. The study identifies grape mealybug and Gill's mealybug as the dominant species with occasional sightings of obscure mealybug and a lack of vine mealybug throughout the sampled vineyard sites. The male mealybugs were monitored using commercially available pheromone delta traps and adhesive band traps. Placement of adhesive band traps in the cordon and trunk of grapevines revealed different male mealybug capture data suggesting their movement within the grapevines. Two generations of mealybugs including the first generation with lower population density emerging out from the overwintering life-stage and the subsequent second generation responsible for colonizing different parts of the grapevines and producing overwintering life-stages were observed. Fifteen genera of ants were sampled from the vineyard via pitfall trap with some ants like pavement ants, acrobat ants, and medium garden ants actively tending and protecting the mealybugs. The use of sugar dispensers in the vineyards also led to lower fruit cluster infestations with mealybugs in comparison to the area without dispensers. The insecticidal spray trial using three different insecticides was also effective in controlling populations of mealybugs on some of the dates after treatment. The research offers valuable insights for grape growers, aiding in the development of effective control strategies for mealybug control. It emphasizes the importance of identifying the species present, understanding their behavior, and exploring potential allies and insecticide options in pest management.

Rastrococcus iceryoides Green (Hemiptera: Pseudococcidae), an alien invasive mealybug pest of Asian origin was first detected in Tanzania in 1989. This pest rapidly spread by the mid-1990s and was soon present in Coastal Kenya and Northern Malawi, where it has been regarded and remains a major pest of mango. Because of its novelty status, there was no information on its biology, ecology and its natural enemies that could aid development of management efforts. This study, therefore, was initiated to establish the bioecology of R. iceryoides and its natural enemies in Kenya and Tanzania, and to explore for efficient co-evolved natural enemies in the aboriginal home of the pest in India. Based on the exploratory survey data, two correlative approaches, Desktop-GARP (Genetic Algorithm for Rule-set Prediction) and Maxent ( Maximum entropy) were used to identify climatically suitable areas in Africa that are agro-meteorologically similar to the aboriginal home of the pest. The first step was to carry out a countrywide survey in Kenya and Tanzania to establish the distribution, host-plant relationship and natural enemies of this pest. The survey revealed that R. iceryoides infested twenty-nine plant species particularly Mangifera indica L. and Cajanus cajan (L.) Millspaugh, and the wild plants Parkinsonia aculeata L., Caesalpinia sepiaria Roxb, and Deinbollia borbonica Scheft. A total of six primary parasitoid species were recovered from R. iceryoides with Anagyrus pseudococci Girault (Hymenoptera: Encyrtidae) predominating. Thirty-eight species of predators belonging to 14 families were also recorded. Despite the presence of these indigenous natural enemies, their ability to regulate the population of R. iceryoides was inadequate. In laboratory host preference studies, M. indica, Cucurbita moschata Duchesne, P. aculeata and C. cajan were found to be the most preferred host plants in view of improving laboratory mass rearing of this pest and the parasitoid. The impact of O. longinoda on the biological control activities of A. pseudococci in the laboratory revealed that percentage parasitism of R. iceryoides by A. pseudococci was significantly higher on ant-excluded trials than on ant-attended trials. Worker ants were observed to remove mummified mealybugs, which resulted in significantly reduced percentage of adult parasitoid eclosion. Oecophylla longinoda showed aggressive behaviour and caused a significant mortality of A. pseudococci during the exposure period. The spatial and temporal population dynamics of this pest was also studied and revealed that populations of R. iceryoides followed an annual cycle which is synchronized with the mango fruiting season, with a peak incidence occurring during the dry season (December to February) on all plant parts. The population dynamics of R. iceryoides and its natural enemies were significantly and positively influenced by temperature, while it was significantly and negatively correlated with rainfall. The exploratory survey in India showed that R. iceryoides is widely distributed throughout the state of Tamil Nadu and infested ten cultivated and wild plant species with extremely low levels of infestation. Percentage parasitism based on the proportion of mummified R. iceryoides was high on all host plants. Out of eleven primary parasitoid species, Praleurocerus viridis Agarwal (Hymenoptera: Encyrtidae) and Anagyrus chryos Noyes&Hayat (Hymenoptera: Encyrtidae) were the most dominant and widely distributed species. In addition to the parasitoids, 10 predator species from 7 families were recorded. Based on the model established with data from India, it was determined that climatically suitable areas for introduction of promising parasitoids in Africa include the humid tropical coastlines of Kenya and Tanzania, as well as some restricted areas in West and Central Africa. Studies of the potential worldwide distribution of R. iceryoides showed that the pest might poses a serious threat on a worldwide scale as it could narrowly become established in all the mango producing countries in the continents. / Thesis (PhD)--University of Pretoria, 2013. / Zoology and Entomology / unrestricted

The vine mealybug, Planococcus ficus (Signoret) (Homoptera: Pseudococcidae) is a pest with significant economic impact on the grape growing industry in South Africa and other parts of the world. With the isolation and synthesizing of the vine mealybug sex pheromone in 2001, new control options for the integrated management of the vine mealybug have been created. The status of sex pheromone monitoring as a tool in the integrated management of the vine mealybug has been evaluated from different perspectives. A significant quantitative difference in male vine mealybug trap catch numbers has been observed between wine and table grape vineyards and results indicated that there were differences in the susceptibility of grape cultivars to vine mealybug. Currently, the delta trap design is the accepted trap design for vine mealybug monitoring. No studies have yet been conducted to determine the optimum trap parameters like size or design. Population pressure may have an influence on the qualitative efficiency of various trap designs. The basis for degree-day forecasting models has been established adequately. However, refinements need to be done and the incorporation of factors such as humidity and regionality also need to be considered. Daily maximum temperatures fluctuating around the upper developmental threshold temperature for prolonged periods of time seemed to suppress population numbers. Different vineyard management practices exist for wine and table grape production. While an action threshold of 65 vine mealybug males per trap per two-week period seems an acceptable threshold for table grape production, it may not be appropriate for wine grape (or raisin grape) production. Using sex pheromone traps for population monitoring is a valid technique in the arsenal of management tactics against the vine mealybug. However, refinements and validation of research results must be done further to build credibility into the monitoring system. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.

As cochonilhas farinhentas (Hemiptera: Pseudococcidae) têm se tornado pragas importantes em diversas culturas. Na videira, são responsáveis por causar danos diretos, resultando em perdas na produção e danos indiretos como vetoras de vírus. Entretanto, poucas informações estão disponíveis sobre a biologia das espécies na cultura. Neste trabalho, foi estudado em laboratório, o efeito de diferentes estruturas vegetativas, cultivares e porta-enxertos de videira no desenvolvimento, sobrevivência e reprodução de Dysmicoccus brevipes (Cockerell, 1893) e Pseudococcus viburni (Signoret, 1875). As exigências térmicas de D. brevipes foram determinadas, sendo estimado o número anual de gerações da espécie nas principais regiões produtoras de uvas de mesa do Brasil. A biologia de D. brevipes foi estudada em folhas de videira das cultivares de uva de mesa Itália (Vitis vinifera) e Niágara Rosada (Vitis labrusca) e em raízes dos porta-enxertos Paulsen 1103 (Vitis berlandieri X Vitis rupestris) e IAC 572 (Vitis caribaea X 101-14 Mgt). As exigências térmicas foram estimadas com base nos dados de biologia obtidos em cinco temperaturas constantes (15, 20, 25, 28 e 30°C) em folhas de videira da cultivar Itália. A biologia de P. viburni foi estudada em folhas de videira das cultivares de uva de mesa Itália e Niágara Rosada. D. brevipes se desenvolveu em diferentes estruturas vegetativas da planta, bem como em diferentes cultivares e porta-enxertos de videira; no entanto, folhas da cultivar Itália foram as mais adequadas ao desenvolvimento da espécie, considerando-se a menor duração do período ninfa-adulto. A taxa líquida de reprodução (Ro) de D. brevipes foi maior em folhas da cultivar Itália (19,82) em relação à cultivar Niágara Rosada (13,78). As ninfas de D. brevipes que sobreviveram nas raízes do porta-enxerto Paulsen 1103, se desenvolveram melhor do que em folhas. Raízes do porta-enxerto IAC 572 foram inadequadas para o desenvolvimento de D. brevipes, originando fêmeas que não se reproduziram. A velocidade de desenvolvimento de D. brevipes aumentou com a elevação da temperatura, sendo a faixa de temperatura entre 20ºC e 30ºC a mais adequada para a espécie. O limiar térmico inferior e superior de desenvolvimento e a constante térmica para o período ninfa-adulto de D. brevipes em folhas de videira da cultivar Itália, foram de 8,2ºC, 34,5°C e 678,42 graus-dia, respectivamente. De acordo com as exigências térmicas de D. brevipes foi possível estimar a ocorrência de 3,4 gerações anuais em Bento Gonçalves (RS), 3,1 em Caxias do Sul (RS), 4,4 em Marialva (PR), 4,8 em Jales (SP) e 5,2 em Petrolina (PE). Através dos dados de longevidade dos adultos e de viabilidade das diferentes fases do ciclo biológico (ninfa-adulto) de fêmeas de P. viburni, verificou-se que a cultivar Niágara Rosada foi mais adequada para o desenvolvimento da espécie. Os resultados deste estudo demonstraram que a planta hospedeira afeta o desenvolvimento e a sobrevivência de D. brevipes e P. viburni e que a escolha da cultivar ou do porta-enxerto a ser utilizado na implantação do vinhedo, pode auxiliar na redução da infestação destas pragas, sendo um componente adicional a ser utilizado em programas de Manejo Integrado na cultura. / Mealybugs (Hemiptera: Pseudococcidae) have become increasingly important pests in many crops. In vineyards, they cause direct damage resulting in production losses and also indirect damages through virus transmission. However, little information is available about the species biology. The effects of different vegetative structures, cultivars and vine rootstocks on the development, survival and reproduction of Dysmicoccus brevipes (Cockerell, 1893) and Pseudococcus viburni (Signoret, 1875) were studied under laboratory conditions. The thermal requirements of D. brevipes were determined and the annual number of generations was estimated for the principal grape-growing regions of Brazil. Biological aspects of D. brevipes were studied using table grape leaves (Itália: Vitis vinifera and Niágara Rosada: Vitis labrusca) and grapevine rootstocks (Paulsen 1103: Vitis berlandieri X Vitis rupestris and IAC 572: Vitis caribaea X 101-14 Mgt). The thermal requirements were estimated using five constant temperatures (15, 20, 25, 28 and 30°C) on Itália table grape leaves. The biology of P. viburni was studied on Itália and Niágara Rosada table grape leaves. D. brevipes developed on different vegetative structures, cultivars and vine rootstocks. However, table grape leaves of V. vinifera Itália were the most suitable for D. brevipes development, considering the shortest developmental period. The net reproductive rate (Ro) of D. brevipes was higher on Itália table grape leaves (19.82) than on Niágara Rosada (13.78). D. brevipes nymphs that survived on Paulsen 1103 roots developed better than on the leaves. Roots of IAC 572 were unsuitable for the development of D. brevipes, resulting in non-reproductive females. The developmental rate of D. brevipes increased with increasing temperature and the range between 20 to 30°C was the most suitable for this species. The predicted upper lethal temperature was 34,5°C, with a minimum threshold for total development at 8,2°C. D. brevipes required 678,42 degree-days to complete development from first instar nymph to the adult stage. According to the thermal requirements, D. brevipes can complete 3.4 annual generations per year in Bento Gonçalves (RS), 3.1 in Caxias do Sul (RS), 4.4 in Marialva (PR), 4.8 in Jales (SP) and 5.,2 in Petrolina (PE). From the the data on adult longevity and the viability of the different female life stages of P. viburni, table grape leaves of V. labrusca Niágara Rosada were the most suitable for development of this species. We conclude that the host plant can affect the development and survival of D. brevipes and P. viburni and that the right choice of the cultivar or vine rootstock to be used in the vineyard can help to reduce pest infestation and is, therefore, an additional component to be included in the integrated pest management of the crop.

Made available in DSpace on 2017-07-10T17:40:46Z (GMT). No. of bitstreams: 1 2014_Tese_Tania_Mari_Vicentini_Prestes.pdf: 1174076 bytes, checksum: e30f8e27973870065b82405ef0c155a9 (MD5) Previous issue date: 2014-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Cassava is cultivated in all regions of Brazil, being the South an important producer of starch, especially in Paraná, which holds 71% of the national amount. In this state, the cultivation is carried out in monoculture, in large areas and using broad-spectrum chemicals, leading in recent years, to an increase of plagues related to this culture, such as cochineal, especially Protortonia navesi. Considering the increase in the occurrence of this species, the aim of this study was to evaluate the biological and morphological parameters of this insect in roots of different varieties of cassava, being the biology and morphology studied in Santa Helena and the comparison of biological parameters among the Cascuda, Baianinha, IAC 90 and Santa Helena. The research was carried out in the Biological Control Laboratory at the State University of West Paraná, UNIOESTE, in Marechal Cândido Rondon, PR, on cassava plants of Santa Helena, Cascuda, Baianinha and IAC 90 varieties. They were removed and replanted in field trays, leaving the tuberous roots portions exposed on soil surface. Cages were fixed over the roots and inside them, a nymph was placed within a day of live, and which was observed daily to obtain the biological parameters. The experimental design was completely randomized. The following biological parameters were evaluated: Instar duration, pre-oviposition, oviposition, fecundity, fertility and embryonic period, survival and morphological characteristics. A fertility life chart was elaborated from data using Tabvida software. To the evaluation of Protortonia navesi biological parameters in different varieties of cassava, the obtained data was analyzed with the aid of Genes app, which underwent to Liliefors analysis and analysis of variance (F test), being the averages compared by the Tukey test at 5% probability. The average life spans of the first, second and third instars were 18, 11.5 and 18.1 days respectively. The pre-oviposition, oviposition and post-oviposition periods were of 4.7, 20.9 and 0.97 days respectively. The reproductive rate was 204 females per female; the capacity of population growth was 0.088; the time to complete a generation was 60.43 days; the finite rate of population growth was 1.09 individuals per day and the time to double the population was 7.88 days. There were differences among the varieties for the parameters of nymph, pre-oviposition, oviposition and fecundity periods. The highest mortality occurred in the first instar of IAC 90 variety. It was observed that IAC 90 interfered in the development of Protortonia navesi, however, further studies are necessary to identify the plant substances that interact in the development of cochineal, as well as studies that provide free choice of the insect to the plant / No Brasil, a mandioca é cultivada em todas as regiões, sendo a região Sul, importante produtora de fécula, destacando-se o Paraná com 71% do volume nacional. Neste Estado, o cultivo é realizado em monocultivo, em grandes áreas e com uso produtos químicos de amplo espectro, levando, nos últimos anos, a um incremento de pragas associadas a esta cultura, como as cochonilhas, destacando-se Protortonia navesi. Considerando o aumento na ocorrência desta espécie, o objetivo deste estudo foi avaliar os parâmetros biológicos e morfológicos deste inseto em raízes de diferentes variedades de mandioca, sendo a biologia e a morfologia estudada na variedade Santa Helena e comparação dos parâmetros biológicos entre as variedades Cascuda, Baianinha, IAC 90 e Santa Helena. Os trabalhos foram realizados no Laboratório de Controle Biológico da Universidade Estadual do Oeste do Paraná, UNIOESTE, de Marechal Cândido Rondon, PR, sobre plantas de mandioca das variedades Santa Helena, Cascuda, Baianinha e IAC 90. Estas foram retiradas do campo e replantadas em bandejas, deixando-se parte das raízes tuberosas expostas sobre a superfície do solo. Gaiolas foram fixadas sobre as raízes e no interior destas foi colocada uma ninfa com até um dia de vida, a qual foi observada diariamente para obtenção dos parâmetros biológicos. O delineamento experimental foi inteiramente casualizado. Foram avaliados os seguintes parâmetros biológicos: duração dos ínstares, períodos de pré-oviposição, oviposição, fecundidade, fertilidade, período embrionário, sobrevivência e características morfológicas. Com os dados foi elaborada tabela de vida de fertilidade utilizando-se o software Tabvida. Para a avaliação dos parâmetros biológicos de Pr. navesi nas diferentes variedades de mandioca, os dados obtidos foram analisados com o auxílio do aplicativo computacional Genes, submetidos à análise de Liliefors e a análise de variância (teste F), sendo as médias comparadas pelo teste de Tukey a 5% de probabilidade. Os períodos médios de vida no primeiro, segundo e terceiro ínstares foram de 18, 11,5 e 18,1 dias, respectivamente. Os períodos pré-oviposição, oviposição e pós-oviposição foram de 4,7, 20,9 e 0,97 dias respectivamente. A taxa líquida de reprodução foi de 204 fêmeas por fêmea, a capacidade de aumento da população foi de 0,088, tempo para completar uma geração foi de 60,43 dias, a razão finita de aumento da população foi de 1,09 indivíduos por dia e o tempo para duplicar a população foi de 7,88 dias. Houve diferenças entre as variedades para os parâmetros períodos de ninfa, de pré-oviposição, de oviposição e a fecundidade. Na variedade IAC 90 ocorreu maior taxa de mortalidade no primeiro ínstar. Verificou-se que variedade IAC 90 interferiu no desenvolvimento de Pr. navesi, entretanto, novos estudos são necessários para identificar as substâncias da planta que interagem no desenvolvimento da cochonilha bem como, trabalhos que proporcionem a livre escolha do inseto à planta

Solenopsis invicta, the red imported fire ant, has recently become associated with Antonina graminis, an invasive pest, and Neodusmetia sangwani, biological control agent, and maybe negatively affecting established biological control. A preliminary survey outlined the range of A. graminis and its parasitoids, and found N. sangwani was present at a reduced rate in South Texas and in the southeastern United States. A greenhouse experiment demonstrated that S. invicta decreased the rate of parasitism of A. graminis by N. sangwani, with S. invicta directly interfering with oviposition. Interactions between S. invicta and A. gaminis may be facilitating the spread and establishment of two invasive pests which has a negative impact on established classical biological control of A. graminis by N. sangwani.

Solenopsis invicta, the red imported fire ant, has recently become associated with Antonina graminis, an invasive pest, and Neodusmetia sangwani, biological control agent, and maybe negatively affecting established biological control. A preliminary survey outlined the range of A. graminis and its parasitoids, and found N. sangwani was present at a reduced rate in South Texas and in the southeastern United States. A greenhouse experiment demonstrated that S. invicta decreased the rate of parasitism of A. graminis by N. sangwani, with S. invicta directly interfering with oviposition. Interactions between S. invicta and A. gaminis may be facilitating the spread and establishment of two invasive pests which has a negative impact on established classical biological control of A. graminis by N. sangwani.

The vine mealybug, Planococcus ficus (Signoret) (Homoptera: Pseudococcidae) is a pest with significant economic impact on the grape growing industry in South Africa and other parts of the world. With the isolation and synthesizing of the vine mealybug sex pheromone in 2001, new control options for the integrated management of the vine mealybug have been created. The status of sex pheromone monitoring as a tool in the integrated management of the vine mealybug has been evaluated from different perspectives. A significant quantitative difference in male vine mealybug trap catch numbers has been observed between wine and table grape vineyards and results indicated that there were differences in the susceptibility of grape cultivars to vine mealybug. Currently, the delta trap design is the accepted trap design for vine mealybug monitoring. No studies have yet been conducted to determine the optimum trap parameters like size or design. Population pressure may have an influence on the qualitative efficiency of various trap designs. The basis for degree-day forecasting models has been established adequately. However, refinements need to be done and the incorporation of factors such as humidity and regionality also need to be considered. Daily maximum temperatures fluctuating around the upper developmental threshold temperature for prolonged periods of time seemed to suppress population numbers. Different vineyard management practices exist for wine and table grape production. While an action threshold of 65 vine mealybug males per trap per two-week period seems an acceptable threshold for table grape production, it may not be appropriate for wine grape (or raisin grape) production. Using sex pheromone traps for population monitoring is a valid technique in the arsenal of management tactics against the vine mealybug. However, refinements and validation of research results must be done further to build credibility into the monitoring system. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.

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