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

Ph.D. (Biochemistry) / This study consistsof two parts namely: • Phosphoproteins in ripening mango fruit tissue: Effect of y-irradiation and various effectors on protein phosphorylation during the climacteric rise, climacteric peak and post-climacteric stages of ripening. • Protein kinase (EC 2.7.10 and EC 2.7.11) activities in ripening mango fruit tissue: Classification, purification and characterisation.

Orientadores: Barbara Janet Teruel Mederos, Roberto Funes Abrahão / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-08T02:04:09Z (GMT). No. of bitstreams: 1 SalazarChacon_NeilFernando_M.pdf: 1380961 bytes, checksum: da7eea90033285a7e1733b3db5b11ab4 (MD5) Previous issue date: 2006 / Resumo: No Brasil as perdas de produtos hortícolas são significativas e dentre as principais causas cita-se o uso de caixas inadequadas e a ausência da cadeia do frio. As caixas para produtos hortícolas disponíveis no mercado, em sua maioria, são desenvolvidas de forma empírica, sem atender às exigências estruturais e área efetiva de aberturas, para facilitar a troca de calor e ventilação. Este trabalho propõe um método de projeto de caixas para mangas (Mangifera Indica L.), baseado em simulação computacional, otimização e validação experimental, buscando minimizar o volume de material construtivo das caixas (madeira de reflorestamento Pinnus Elliotti), associado a aspectos estruturais, ergonômicos e distribuição da área efetiva de aberturas. Foram projetados e construídos três protótipos de caixas, de ripas retas com diferentes configurações e área efetiva de aberturas (54% e 36%). A eficiência do resfriamento das mangas (variedade Tommy Atkins) foi avaliada através da determinação do tempo de resfriamento de 6 kg de frutas, acondicionadas nos três modelos desenvolvidos, e submetidas ao resfriamento rápido num sistema com ar forçado e duas vazões de ar (0,22 m3 s- 1 e 0,43 m3 s-1), a uma temperatura de 6ºC e umidade relativa média de 85±2,1%. O tempo de resfriamento das frutas também foi determinado quando a mesma quantidade foi condicionada nas caixas de papelão usadas comercialmente (7% e 0% de área efetiva de abertura). Foi aplicado o Método dos Elementos Finitos implementado no programa ANSYS, para o dimensionamento e otimização estrutural do modelo com o melhor comportamento com relação ao resfriamento. Todas caixas de madeira contendo frutas foram submetidas a ensaios de vibração, por um período de duas horas e uma freqüência de 20 Hz. Não houve diferença significativa no meio tempo de resfriamento dos frutos acondicionados nas caixas de madeira (38,00±1,70 min), no entanto na comparação com as caixas de papelão a diferença foi significativa (82,74±29,58 min). O modelo escolhido para a otimização estrutural possuía 36% de área efetiva de aberturas e duas ripas laterais. Após a otimização a diminuição de volume total de material foi de 60% e a redução da seção transversal das colunas da ordem de 83%, com relação às condições iniciais de projeto. Não houve indícios de danos mecânicos nas frutas depois de submetidas à vibração. A simulação computacional para o estudo estrutural, acoplada a algoritmos de otimização, pode ser usada como ferramenta de apoio para desenvolver projetos de caixas de madeira, com grande aproximação, atendendo a critérios geométricos, ergonômicos e térmicos / Abstract: Horticulture product losses in Brazil are significant and among the main causes for this are the use of inappropriate boxes and the absence of the cold chain. Most of the boxes available in the market for horticulture products are developed empirically without satisfying structural demands and the openings effective area for to facilitate the exchange of heat and ventilation. This study proposes a project method for mango boxes (Mangifera Indica L.) based on computer simulations, optimization and experimental validation, seeking to minimize the amount of construction material for the boxes (reforestation wood - Pinnus Elliotti) associated with structural and ergonomic aspects and the openings effective area. Three box prototypes were designed and built using straight laths with different configurations and openings effective area (54% and 36%). The cooling efficiency the mango (Tommy Atkins variety) was evaluated by determining the cooling time for 6 kg of fruit packed in the three different models and submitted to cooling in a forced-air system and two air flows (0.22 m3 s- 1 and 0.43 m3 s-1), at a temperature of 6ºC and average relative humidity of 85±2.1%. Fruit cooling time was also determined when the same amount was packed in the commercially used cardboard boxes (7% and 0% of openings effective area). The Finite Element Method was applied, implemented in the ANSYS program, for the dimensioning and structural optimization of the model with the best behavior in relation to cooling. All wooden boxes with fruit underwent vibration testing for a two hour period at a frequency of 20 Hz. There was no significant difference in average cooling time for fruit packed in the wooden boxes (36.08±1.44 min); however, the difference was significant in comparison to the cardboard boxes (82.63±29.64 min). The model chosen for structural optimization had a 36% openings effective area and two side laths. After optimization, the reduction in total volume of material was 60% and the reduction in the cross section for columns was about 83% compared to the project¿s initial conditions. There was no indication of mechanical damage in the fruit after it underwent vibration testing. Computer simulations for the structural study, together with optimization algorithms, can be used as an effective support tool to develop projects for wooden boxes, with geometric, ergonomic and thermal criteria / Mestrado / Tecnologia Pós-Colheita / Mestre em Engenharia Agrícola

No description available.

El presente estudio tiene como objetivo determinar la pre-factibilidad de la instalación de una planta procesadora de conservas de mango en almíbar a partir de la evaluación de la viabilidad de mercado, tecnológica, económica y financiera. Para la elaboración de conservas se utilizará como materia prima principal el mango nacional de gran calidad y reconocimiento. Esta investigación resulta relevante debido a que en los últimos años el precio de las conservas se ha ido incrementando debido a la creciente demanda existente por estos productos. Otro aspecto importante para la relevancia de esta investigación es que se le dará valor agregado al mango peruano. / Trabajo de investigación

Foi feita uma revisão bibliográfia sobre a aplicação da amostragem seqüencial em manejos de pragas. A metodologia para o desenvolvimento de planos de amostragem seqüencial, foi baseada na teoria de Wald. Verificou-se que a distribuição binomial ajustou-se aos dados de presença-ausência da cochonilha-branca Aulacaspis tubercularis na cultura da manga, obtidos em duas propriedades localizadas na região de Jaboticabal, interior do estado de São Paulo. Seis planos de amostragem seqüencial foram elaborados para o monitoramento dessa praga, três com níveis de erros iguais a 0; 20 e outros três com níveis de erros iguais a 0; 10. Dentre esses, foram elaborados: dois planos para a amostragem em ramos durante o período vegetativo, dois para a amostragem em ramos durante o período de frutificação e outros dois planos para a amostragem em frutos. Nos planos de amostragem seqüencial para ramos no período vegetativo foram utilizados níveis de segurança iguais a 0; 35 e níveis de dano econômico iguais a 0; 50. Já no período de frutificação, houve um rigor maior quanto ao uso desses níveis, devido à presença de frutos. Foram utilizados níveis de segurança iguais a 0; 20 para ramos e 0; 05 para frutos, e níveis de dano econômico iguais a 0; 30 e 0; 15 para ramos e frutos, respectivamente. Foram construídas tabelas para o processo de amostragem em campo, facilitando assim, o trabalho do amostrador. Com o uso dessas tabelas o produtor poderá decidir rapidamente se há, ou não, a necessidade de se realizar o controle dessa praga. / A bibliographical revision on the application of the sequential sampling in management of pests was made. The methodology for the development of plans of sequential sampling, was based on the theory of Wald. It was verified that the binomial distribution adjusted to data of presence-absence of the mango scale Aulacaspis tubercularis on mango crop, gotten in two properties located at the region of Jaboticabal, interior of the state of São Paulo. Six plans of sequential sampling was elaborated for the monitoring of this pest, three with errors levels equal to 0; 20 and others three with errors levels equals to 0; 10. Amongst these, they was elaborated: two plans for the sampling in branches during the vegetative period, two for the sampling in branches during the period of fructification and others two plans for the sampling in fruits. In the plans of sequential sampling for branches in the vegetative period security level equal to 0; 35 and economic damage level equal to 0; 50 had been used. Already in longer period of fructification, had a bigger severity how much to the use of these levels, due to presence of fruits. Security levels equals to 0; 20 for branches and 0; 05 for fruits, and economic damage levels equals to 0; 30 and 0; 15 for branches and fruits, respectively, had been used. Tables for the sampling process in field, thus facilitating, the sampler's work was constructed. With the use of these tables the producer will be able to decide quickly has itself, or not, the necessity of if carrying through the control from this pest.

<p>The main objective of this study was to identify ways in which transaction costs can be lowered to improve small-scale farmers&rsquo / participation in and returns from agricultural output markets, with specific reference to small-scale mango farmers in Limpopo province. This study hypothesizes that transaction costs are lower in informal spot markets and increase when small-scale farmers sell in more structured markets (formal markets). This study builds on transaction cost economics (TCE) to demonstrate how to overcome transaction cost barriers that small-scale mango farmers face in the agro-food markets. The approach to collect primary information was sequenced in two steps: first, key informant and focus group interviews were conducted and, secondly, a structured survey instrument was administered in two districts of Limpopo. A total of 235 smallscale mango farmers were interviewed. A binary logistic regression model was used to estimate the impact of transaction costs on the likelihood of households&rsquo / participation in formal (=1) and informal (=0) agro-food markets. STATA Version 10 was used to analyse the data. This study found that a larger proportion of male than female farming households reported participation in the formal markets, suggesting deep-seated gender differentiation in market participation. The average age of small farmers participating in formal markets is 52, compared to 44 for those in informal markets, implying that older farmers might have established stronger networks and acquired experience over a longer period. Farmers staying very far from the densely populated towns (more than 50 km) participate less in the formal markets than those staying closer (0 &ndash / 25 km and 26 &ndash / 49 km), which implies that the further they are from the towns, the less the likelihood of farmers selling in the formal markets. Farmers who own storage facilities and a bakkie (transportation means) participate more in formal markets compared to those who do not own these assets, which suggests that these farmers are able to store mangoes, retaining their freshness and subsequently delivering them to various agro-food markets on time. Households that participate in formal markets have high mean values of income and social grants. However, this study found that the likelihood of a household&rsquo / s participation in the markets is less as income and social grants increase. This suggests that households do not invest their financial assets in order to overcome market access barriers. A large proportion of households that own larger pieces of arable land participate in the formal markets, which implies that they are able to produce marketable surplus. Households that have a high mean value (in Rand) of cattle participate more in formal markets than in informal markets. However, this study found that the likelihood of a household&rsquo / s participation in the markets does not change with an increase in the value of its livestock. These findings suggest that households do not sell their cattle in order to overcome market access barriers. Reduced transaction costs for small-scale mango farmers in Limpopo should improve their participation in and returns from the agro-food markets. Policy interventions to support this need to focus on: access to storage and transportation facilities, enforcement of gender equity requirements in existing policies, and better access to information about markets.</p>

<p>The main objective of this study was to identify ways in which transaction costs can be lowered to improve small-scale farmers&rsquo / participation in and returns from agricultural output markets, with specific reference to small-scale mango farmers in Limpopo province. This study hypothesizes that transaction costs are lower in informal spot markets and increase when small-scale farmers sell in more structured markets (formal markets). This study builds on transaction cost economics (TCE) to demonstrate how to overcome transaction cost barriers that small-scale mango farmers face in the agro-food markets. The approach to collect primary information was sequenced in two steps: first, key informant and focus group interviews were conducted and, secondly, a structured survey instrument was administered in two districts of Limpopo. A total of 235 smallscale mango farmers were interviewed. A binary logistic regression model was used to estimate the impact of transaction costs on the likelihood of households&rsquo / participation in formal (=1) and informal (=0) agro-food markets. STATA Version 10 was used to analyse the data. This study found that a larger proportion of male than female farming households reported participation in the formal markets, suggesting deep-seated gender differentiation in market participation. The average age of small farmers participating in formal markets is 52, compared to 44 for those in informal markets, implying that older farmers might have established stronger networks and acquired experience over a longer period. Farmers staying very far from the densely populated towns (more than 50 km) participate less in the formal markets than those staying closer (0 &ndash / 25 km and 26 &ndash / 49 km), which implies that the further they are from the towns, the less the likelihood of farmers selling in the formal markets. Farmers who own storage facilities and a bakkie (transportation means) participate more in formal markets compared to those who do not own these assets, which suggests that these farmers are able to store mangoes, retaining their freshness and subsequently delivering them to various agro-food markets on time. Households that participate in formal markets have high mean values of income and social grants. However, this study found that the likelihood of a household&rsquo / s participation in the markets is less as income and social grants increase. This suggests that households do not invest their financial assets in order to overcome market access barriers. A large proportion of households that own larger pieces of arable land participate in the formal markets, which implies that they are able to produce marketable surplus. Households that have a high mean value (in Rand) of cattle participate more in formal markets than in informal markets. However, this study found that the likelihood of a household&rsquo / s participation in the markets does not change with an increase in the value of its livestock. These findings suggest that households do not sell their cattle in order to overcome market access barriers. Reduced transaction costs for small-scale mango farmers in Limpopo should improve their participation in and returns from the agro-food markets. Policy interventions to support this need to focus on: access to storage and transportation facilities, enforcement of gender equity requirements in existing policies, and better access to information about markets.</p>

Foi feita uma revisão bibliográfia sobre a aplicação da amostragem seqüencial em manejos de pragas. A metodologia para o desenvolvimento de planos de amostragem seqüencial, foi baseada na teoria de Wald. Verificou-se que a distribuição binomial ajustou-se aos dados de presença-ausência da cochonilha-branca Aulacaspis tubercularis na cultura da manga, obtidos em duas propriedades localizadas na região de Jaboticabal, interior do estado de São Paulo. Seis planos de amostragem seqüencial foram elaborados para o monitoramento dessa praga, três com níveis de erros iguais a 0; 20 e outros três com níveis de erros iguais a 0; 10. Dentre esses, foram elaborados: dois planos para a amostragem em ramos durante o período vegetativo, dois para a amostragem em ramos durante o período de frutificação e outros dois planos para a amostragem em frutos. Nos planos de amostragem seqüencial para ramos no período vegetativo foram utilizados níveis de segurança iguais a 0; 35 e níveis de dano econômico iguais a 0; 50. Já no período de frutificação, houve um rigor maior quanto ao uso desses níveis, devido à presença de frutos. Foram utilizados níveis de segurança iguais a 0; 20 para ramos e 0; 05 para frutos, e níveis de dano econômico iguais a 0; 30 e 0; 15 para ramos e frutos, respectivamente. Foram construídas tabelas para o processo de amostragem em campo, facilitando assim, o trabalho do amostrador. Com o uso dessas tabelas o produtor poderá decidir rapidamente se há, ou não, a necessidade de se realizar o controle dessa praga. / A bibliographical revision on the application of the sequential sampling in management of pests was made. The methodology for the development of plans of sequential sampling, was based on the theory of Wald. It was verified that the binomial distribution adjusted to data of presence-absence of the mango scale Aulacaspis tubercularis on mango crop, gotten in two properties located at the region of Jaboticabal, interior of the state of São Paulo. Six plans of sequential sampling was elaborated for the monitoring of this pest, three with errors levels equal to 0; 20 and others three with errors levels equals to 0; 10. Amongst these, they was elaborated: two plans for the sampling in branches during the vegetative period, two for the sampling in branches during the period of fructification and others two plans for the sampling in fruits. In the plans of sequential sampling for branches in the vegetative period security level equal to 0; 35 and economic damage level equal to 0; 50 had been used. Already in longer period of fructification, had a bigger severity how much to the use of these levels, due to presence of fruits. Security levels equals to 0; 20 for branches and 0; 05 for fruits, and economic damage levels equals to 0; 30 and 0; 15 for branches and fruits, respectively, had been used. Tables for the sampling process in field, thus facilitating, the sampler's work was constructed. With the use of these tables the producer will be able to decide quickly has itself, or not, the necessity of if carrying through the control from this pest.

Magister Economicae - MEcon / The main objective of this study was to identify ways in which transaction costs can be lowered to improve small-scale farmers’ participation in and returns from agricultural output markets, with specific reference to small-scale mango farmers in Limpopo province. This study hypothesizes that transaction costs are lower in informal spot markets and increase when small-scale farmers sell in more structured markets (formal markets). This study builds on transaction cost economics (TCE) to demonstrate how to overcome transaction cost barriers that small-scale mango farmers face in the agro-food markets. The approach to collect primary information was sequenced in two steps: first, key informant and focus group interviews were conducted and, secondly, a structured survey instrument was administered in two districts of Limpopo. A total of 235 smallscale mango farmers were interviewed. A binary logistic regression model was used to estimate the impact of transaction costs on the likelihood of households’ participation in formal (=1) and informal (=0) agro-food markets. STATA Version 10 was used to analyse the data. This study found that a larger proportion of male than female farming households reported participation in the formal markets, suggesting deep-seated gender differentiation in market participation. The average age of small farmers participating in formal markets is 52, compared to 44 for those in informal markets, implying that older farmers might have established stronger networks and acquired experience over a longer period. Farmers staying very far from the densely populated towns (more than 50 km) participate less in the formal markets than those staying closer (0 – 25 km and 26 – 49 km), which implies that the further they are from the towns, the less the likelihood of farmers selling in the formal markets. Farmers who own storage facilities and a bakkie (transportation means) participate more in formal markets compared to those who do not own these assets, which suggests that these farmers are able to store mangoes, retaining their freshness and subsequently delivering them to various agro-food markets on time. Households that participate in formal markets have high mean values of income and social grants. However, this study found that the likelihood of a household’s participation in the markets is less as income and social grants increase. This suggests that households do not invest their financial assets in order to overcome market access barriers. A large proportion of households that own larger pieces of arable land participate in the formal markets, which implies that they are able to produce marketable surplus. Households that have a high mean value (in Rand) of cattle participate more in formal markets than in informal markets. However, this study found that the likelihood of a household’s participation in the markets does not change with an increase in the value of its livestock. These findings suggest that households do not sell their cattle in order to overcome market access barriers. Reduced transaction costs for small-scale mango farmers in Limpopo should improve their participation in and returns from the agro-food markets. Policy interventions to support this need to focus on: access to storage and transportation facilities, enforcement of gender equity requirements in existing policies, and better access to information about markets. / South Africa