Field studies of the blackmargined aphid, Monellia caryella (Fitch), were conducted on three cultivars, ‘Cheyenne’, ‘Kiowa’, and ‘Pawnee’, of pecan, Carya illinoinensis (Koch). Aphid density and natural enemy (lacewings, ladybird beetles, and spiders) densities were determined biweekly by direct inspection of 160 leaves per variety during the 2005 and 2006 growing seasons. Honeydew deposition was measured biweekly using water sensitive cards. Aphid phenologies were similar among cultivars; however, ‘Cheyenne’ supported higher densities of aphids than either ‘Kiowa’ or ‘Pawnee’. Honeydew production correlated positively with aphid density. Honeydew produced per aphid differed only between ‘Cheyenne’ and ‘Pawnee’ in 2006; natural enemies per aphid varied in significance during both seasons. Natural enemy densities increased during initial stages of outbreak on all cultivars in 2006. The asymptote reached on ‘Cheyenne’ had a lower natural enemy to aphid ratio than that on the other cultivars, indicating that the functional response of natural enemies to increased aphid densities was exhausted sooner on ‘Cheyenne than on other cultivars’. Honeydew appears to be an attractant for natural enemies and cost-benefit calculations were made to quantify the loss of photosynthates to aphids for each cultivar versus the gain in natural enemies that occurred. ‘Cheyenne’ was the least efficient of the three cultivars in the utilization of this defense mechanism. The energy drain per hectare attributable by adult aphid feeding was, 761,197 – 900,312kcal, 266,397 – 237,709kcal, and 138,790 – 134,223kcal for ‘Cheyenne’, ‘Kiowa’, and ‘Pawnee’, respectively. Calculated nut-loss equivalents were 14 – 16kg for ‘Cheyenne’, 4 – 5kg for ‘Kiowa’, and 2kg for ‘Pawnee’.

Field studies of the blackmargined aphid, Monellia caryella (Fitch), were conducted on three cultivars, 'Cheyenne', 'Kiowa', and 'Pawnee', of pecan, Carya illinoinensis (Koch). Aphid density and natural enemy (lacewings, ladybird beetles, and spiders) densities were determined biweekly by direct inspection of 160 leaves per variety during the 2005 and 2006 growing seasons. Honeydew deposition was measured biweekly using water sensitive cards. Aphid phenologies were similar among cultivars; however, 'Cheyenne' supported higher densities of aphids than either 'Kiowa' or 'Pawnee'. Honeydew production correlated positively with aphid density. Honeydew produced per aphid differed only between 'Cheyenne' and 'Pawnee' in 2006; natural enemies per aphid varied in significance during both seasons. Natural enemy densities increased during initial stages of outbreak on all cultivars in 2006. The asymptote reached on 'Cheyenne' had a lower natural enemy to aphid ratio than that on the other cultivars, indicating that the functional response of natural enemies to increased aphid densities was exhausted sooner on 'Cheyenne than on other cultivars'. Honeydew appears to be an attractant for natural enemies and cost-benefit calculations were made to quantify the loss of photosynthates to aphids for each cultivar versus the gain in natural enemies that occurred. 'Cheyenne' was the least efficient of the three cultivars in the utilization of this defense mechanism. The energy drain per hectare attributable by adult aphid feeding was, 761,197 - 900,312kcal, 266,397 - 237,709kcal, and 138,790 - 134,223kcal for 'Cheyenne' , 'Kiowa', and 'Pawnee', respectively. Calculated nut-loss equivalents were 14 - 16kg for 'Cheyenne', 4 - 5kg for 'Kiowa', and 2kg for 'Pawnee'.

In New Zealand Nothofagus forests Ultracoelostoma spp. scale insects produce abundant honeydew which is an important food for native birds, invertebrates, sooty mould, and invasive wasps. Previous models have underestimated honeydew production, potentially because they do not allow for the flow rate of honeydew to vary between insects based on characteristics such as insect size. This research focused on honeydew production rates at the level of the individual insect, how insect characteristics influence production, and whether the strongest predictor of production, ambient air temperature, acts directly on insects or indirectly via effects on trees. Finding out how temperature acts to increase honeydew production will better reveal the physiological processes involved. The study site was Mt. Richardson, Canterbury. In the first part of this study, during March-April 2012, daily mean ambient temperature (range 7.2 – 15.1 °C) had a positive relationship with honeydew production. Insect size positively influenced production at high temperatures, with the largest insects producing 0.296 µg insect⁻¹ h⁻¹ and the smallest insects 0.115 µg insect⁻¹ h⁻¹ at the highest temperature, 15.1 °C. In the second part of this study, during October 2012-January 2013, I manipulated temperature on areas of tree trunk using reflective or clear plastic covers, creating a mean temperature difference of 1.1 °C. However, the effects of tree and insect temperature could not be separated as there was no relationship between either manipulated or ambient temperature and honeydew production. These results show that honeydew production is influenced by individual insect characteristics. This will be important for future models of production. The results also show contradictory effects of temperature on honeydew production, perhaps because of interactions with other unknown factors, which bears further investigation.

The topic of this diploma thesis is to evaluate the impact of grazing on the quality of bee honey. The theoretical part focuses on the characteristics of the individual kinds of honey and their different compositions. The fundamental physical and chemical requirements for honey are described there, including a sensory requirement, which indicates Public Notice No. 76/2003 Coll. The practical part contains the physico-chemical analysis itself, according to the Harmonised methods of the European Honey. The two fundamental kinds of honey were evaluated, i.e. blossom and honeydew honey. Each type of honey was represented by 20 samples. Subsequently, the following parameters were monitored: water content, acidity, pH, electrical conductivity, content of water-insoluble substances and also the test for the evidence of damage of honey structure by starch syrup was done. The comparison of the samples shows that the different types of honey vary mostly in the parameter of electrical conductivity. The final results show that the different bee grazing does not impact the quality of honey.

The theme of this thesis is a comparison of selected quality indicators of samples from single-flower honeys from the area of the Czech Republic and honeys from different retail chains. The theoretical part focuses on the characteristics of the individual kinds of honey and how different their composition is. There are described basic physical and chemical requirements for honey including sensory requirements which are specified in Regulation No.76/2003 Code. The practical part contains a physically-chemical analysis according to the Harmonized methods of European Honey and a sensory evaluation of selected single-flower honeys (honeydew, acacia, lime, sunflower and rape). There were analysed twenty samples of honey from Czech beekeepers and fifteen samples of honey bought in different retail chains in the Czech Republic. Subsequently, these parameters were monitored - water content and acidity. Next step was a test for evidence of disruption by starchy sugar and malt extracts. Then, sensory requirements such as colour, smell, taste and consistence were evaluated. The conclusion of the comparison of honey samples indicates that individual honey samples differed the most in the taste and smell criteria and in addition the samples were often disrupted by starchy sugar and malt extracts. The samples collected from the beekeepers from the area of the Czech Republic complied with Regulation No.76/2003 Code. On the contrary, the samples from the chosen retail chains in the Czech Republic weren't in accordance with the criteria specified in Regulation No.76/2003 Code.

The thesis deals with an incidence of so-called cement (melecitose) honey, which can cause serious problems to a beekeeper in the form of losses of bee colonies, honey as well as beewax works. It is a honeydew honey with a higher content of the trisaccharide of melezitose, which causes a quick crystallization in comb cells. A high concentration of this trisaccharide which consists of two molecules of glucose and one molecule of fructose is caused by some representatives of hemipteran insect. Reverse invertases present in hemipteran bodies cause synthesis of oligosaccharides, including the trisaccharide melezitose, from monosaccharides. Content of this trisaccharide is determining for the formation of the cement honey. Above 10 % it can cause quick crystallization of honey. Incidence of the melezitosis is increased by many factors of which the most important is weather suitable for reproduction of honeydew producers followed by a dry period during which water content in the honeydew decreases and the content of saccharides increases. Other important factors are health of the bee colony and species composition of the honeydew sources. Aim of the thesis was to analyse incidence of melecitose honey in the region of Český Krumlov over the period of several years depending of the length of active period of the individual bee keepers. Influence of altitude, year, weather, number of bee colonies, and species composition of honey flow sources was also evaluated. The thesis also presents methods of cement honey processing as used by beekeepers who have recently experienced this problem. The most frequently used method is dipping combs in water with subsequent reworking of the solution by honeybees. Zootechnical methods of beekeeping reflecting the problems of the incidence of cement honey are outlined in the theoretic part of the thesis.

Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-09-26T19:12:51Z No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:33:46Z (GMT) No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:33:51Z (GMT) No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) / Made available in DSpace on 2016-10-04T18:34:00Z (GMT). No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) Previous issue date: 2015-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Aphids are important pests in agriculture, mainly because they are vectors of phyto-pathogenic virus. One of the ways to control these insects, is the use of botanical insecticides. However in order to the control to be effective it is also necessary to know their biological characteristics. In this context, the aim of the present study was to evaluate the bioactivity of several plant extracts upon Toxoptera citricidus, presently considered one of the most important pests of citric plantations. For this purpose its life cycle has been studies and important metabolic processes as: consumption, production, respiration and excretion were quantified. Based on these data the species life table and energy budget were constructed. The bioactivity of 11 species of plants including a nanoformulation of the neen, Azadirachta indica, was evaluated through acute toxicity tests. T. citricidus was maintained on Citrus limonia under controlled constant conditions in the laboratory. Among these 5 had insecticide activity upon T. citricidus causing mortality to 80 % of the individuals tested or more. The lethal median concentration (CL50 48h) varied from 0.17 to 4.10 mg/mL for the nynphal phases and from 0.30 to 5.01 mg/mL to adults thus evidencing insecticide properties and presenting high to be used in the management of this pest. A magnetic nuclear ressonance of honeydew, the excretion product of this aphid, evidenced the presence of important aminoacids besides carbohydrates allowing an advance in the knowledge on aphid-ants and aphid- host plant. The total energy budget of of T. citricidus varied According to the aphid age. Mean daily energy consumption were 0.3717 cal for nymphs and 0.4761cal for adults. The energy fraction invested in production by T. citricidus was high, with a mean value around 60%, evidencing high efficiency of energy retention. It was concluded that considering its biological characteristics T. citricidus has a relevant role in the energy transference across the ecosystem. / Os afídeos são importantes pragas na agricultura, principalmente por serem vetores de vírus fitopatogênicos. Entre as formas de controle desses insetos, estão incluídos os inseticidas botânicos, no entanto, para que o seu controle seja eficiente é necessário também que se conheçam as suas características biológicas. Nesse contexto, esse trabalho teve como objetivo avaliar a bioatividade de diversos extratos vegetais sobre Toxoptera citricidus, considerado uma das mais importantes pragas das plantações cítricas. Para isso foi estudado o ciclo de vida e quantificados importantes processos metabólicos, como: consumo, produção, respiração e excreção, e com base nestes, determinado o balanço energético e construída a tabela de vida da espécie. A bioatividade de 11 espécies de plantas incluindo uma nanoformulação do nim, Azadirachta indica, foi avaliada por meio de toxicidade aguda. Para isso T. citricidus foi mantida sobre Citrus limonia em condições controladas e contantes de laboratório. Destas, 5 espécies tiveram ação inseticida sobre T. citricidus, causando mortalidade igual ou superior a 80%. A concentração letal mediana (CL50) variou de 0,17 a 4,10 mg/mL para ninfas e de 0,30 a 5,01 mg/mL para adultos, assim evidenciando propriedades inseticidas e apresentando elevado potencial para serem utilizados no manejo dessa praga. Uma análise por ressonância magnética nuclear do honeydew permitiu evidenciar a presença de importantes aminoácidos além de carboidratos permitindo aprofundar o conhecimento sobre as interações afídeo-formiga e afídeoplanta hospedeira. O balanço energético total do T. citricidus variou dependendo da idade do afídeo. O consumo energético diário foi em média 0,3717 cal para as ninfas e de 0,4761 cal para os adultos. A fração energética à produção foi bastante elevada, em média 60%, evidenciando alta eficiência na retenção de energia. Conclui-se que T. citricidus tem importante papel na transferência de energia através dos ecossistemas.

The research project investigated whether victims of housebreaking experienced motivational, cognitive and emotional deficits central to the Learned Helplessness phenomenon. In keeping with the Reformulated Learned Helplessness theory the attributional style of victims, were also assessed. The State-Trait Inventory developed by Spielberger, Gorsuch, Lushene, Vagg and Jacobs was administered to measure the anxiety levels of victims. Sub-goals served as illustration for the learned helplessness phenomenon. Three- hundred victims, using probability sampling techniques, were interviewed by means of an interview schedule. Support was found for cognitive and some motivational deficits and a common range of emotions experienced by victims. The majority of victims exhibited a global attnbutional style. Burglary victims did not show appreciably higher trait and state scores means, except for females in the 19-39 age group, when compared to a psychological norm. Environmental factors did play a role in rendering homes vulnerable. Recommendations addressing the fear of housebreaking were made at a therapeutic and practical level. / Sociology / M.A. (Criminology)

The research project investigated whether victims of housebreaking experienced motivational, cognitive and emotional deficits central to the Learned Helplessness phenomenon. In keeping with the Reformulated Learned Helplessness theory the attributional style of victims, were also assessed. The State-Trait Inventory developed by Spielberger, Gorsuch, Lushene, Vagg and Jacobs was administered to measure the anxiety levels of victims. Sub-goals served as illustration for the learned helplessness phenomenon. Three- hundred victims, using probability sampling techniques, were interviewed by means of an interview schedule. Support was found for cognitive and some motivational deficits and a common range of emotions experienced by victims. The majority of victims exhibited a global attnbutional style. Burglary victims did not show appreciably higher trait and state scores means, except for females in the 19-39 age group, when compared to a psychological norm. Environmental factors did play a role in rendering homes vulnerable. Recommendations addressing the fear of housebreaking were made at a therapeutic and practical level. / Sociology / M.A. (Criminology)