In the United States, we have been battling the bed bug (Cimex lectularius L.) resurgence for over ten years. Current treatment methods are labor intensive, time consuming, and very expensive. Many studies have evaluated the efficacy of treatment methods, but few have focused on bed bug suppression in multi-unit housing. Low income, multi-unit housing residents lack basic bed bug knowledge and are particulary vulnerable to bed bug infestations because they are unable to afford conventional treatment. In this study, diatomaceous earth (D.E.), an inexpensive desiccant dust labeled for bed bug control, was evaluated for its efficacy in killing bed bugs, and determined to be successful. A proactive bed bug suppression program that included D.E. was implemented in a low-income housing facility in Harrisonburg, VA. The program consisted of inexpensive, low toxicity, integrated bed bug management methods, including a novel strategy for applying a perimeter barrier of D.E. in apartment units (n = 121). Over the course of one year, both the number of initial infestations and the costs associated with bed bug treatments were reduced. Low-income, multi-unit housing residents (n = 479) from three cities (Harrisonburg and Richmond, VA; New Orleans, LA) were surveyed before and after an educational seminar to assess their bed bug. After attending the seminar, residents (n = 112) significantly improved (P < 0.0001) their bed bug knowledge, and were able to correctly answer more bed bug-related questions than they had before the educational seminar. / Master of Science in Life Sciences

This study evaluates the effectiveness and impacts of USAID's IPM IL vegetable technology transfer subproject in Bangladesh. The effectiveness of the technology transfer is evaluated in four ways: IPM adoption rates and determinants of IPM adoption, measuring the impact of IPM adoption on vegetable yields, pest management costs, and the number of pesticide applications used, estimation of the economic impacts of IPM adoption and the technology transfer, and analysis of the relative efficiency of the various technology transfer methods used to transfer the IPM practices to farmers. Adoption determinants were identified using traditional and ordered probit regression analysis. Difference-in-difference models were used to identify the impacts of IPM adoption on yields, pest management costs, and the number of pesticide applications applied. Economic impacts of IPM technology adoption were measured using economic surplus analysis. Finally, to compare the relative efficiency of different technology transfer methods, adoption rates were identified for each transfer method and combined with the training cost per farmer to identify the cost per farmer adopting IPM practices. The results from the adoption analysis suggest the number of years of agricultural experience of the household head, the number of IPM adopters known by the household, and learning agricultural information from media sources and/or farm training events such as field days significantly increase the likelihood of IPM adoption. The impacts of IPM adoption on vegetable yields, pest management costs, and the number of pesticide applications were non-significant for vegetable crops. Analysis of the cost efficiency of the different IPM technology transfer methods suggests that media sources such as television, radio, and newspapers have the lowest cost per farmer. / Master of Science

The two papers in this thesis are aimed at solving problems in Integrated Pest Management project, practice, and program evaluations. In the first paper, an evaluation design is constructed for the Onion ipmPIPE website, an onion pest information website. The Bayesian decision theoretic approach may not accurately model onion growers' pest management decisions throughout the season. Randomization of the treatment is possible, but an incomplete grower list proved to be a problem. The analysis shows that an instrumental variables approach may be the most appropriate method for estimating the impact of the Onion ipmPIPE website because its data needs are solved by using USDA-NASS surveying services. In the second paper, the challenge is to develop a practical method to measure benefits accruing to women from agricultural research using secondary data. Donors, governments and others are interested in determining how benefits from agricultural research accrue to women. We develop a three-step framework to identify women's crops and technologies. In step one, total potential benefits from research are estimated; step two allocates those benefits between men and women; step three, incorporates technology-specific parameters to refine the estimates of potential benefits. We apply this framework to Honduras and find that steps one and two provide the most information on the magnitude and distribution of benefits, but that refinements in step three can affect rankings of research program impacts on women. / Master of Science

Potato farmers in Ecuador rely on chemical inputs to manage pests and optimize yields. IPM techniques are recommended to lower production costs, reduce exposure to pesticides, and improve the long-term sustainability of the agriculture system. We conducted a survey of 109 potato farmers in Carchi, Ecuador that included 30 Farmer Field School (FFS) participants, 28 farmers who had been exposed to FFS-participants, and 51 randomly selected farmers. Using an ordered probit model, the data were analyzed to identify determinants and constraints of adoption. Access to information through FFS was the main determinant of adoption of IPM, followed by field days, pamphlets, and exposure to FFS-participants. The study looked at the relative cost-effectiveness of information dissemination methods and found that field days and pamphlets have strong impacts on adoption considering their low cost of implementation. The only significant household variable was household size, where larger households adopted less IPM. Per capita land holdings were not significant in the model. There is evidence of farmer-to-farmer diffusion from FFS to non-FFS farmers. Further research is necessary to evaluate the nature and quality of information transfer between farmers. The study was limited by the small sample size and non-random selection of farmer respondents. / Master of Science

Smallholder farmers in Honduras and the Trifinio region of Central America contend with poor roads and high transportation costs when making production decisions. Farmers select crop activities based on cost, revenue and profit but are constrained by labor requirements, cash requirements, food security concerns, and input and output market access. Market access is directly related to distance to market. Distance to market increases the cost of inputs, increases transportation costs, and reduces the effective price farmers receive for outputs. We conduct two analyses to study the impact of distance to market on crop and technology choices. We utilize a household survey to analyze the determinants of fruit and vegetable production and market participation. Probit and multinomial logit models are employed to analyze the impact of distance to market and other variables on fruit and vegetable production. Results indicate that as distance to market increases, the probability of fruit and vegetable production for consumption increases and the probability of fruit and vegetable production for sale at market decreases. In a second paper, we utilize data from extension agencies, research institutions, a household survey, and expert opinions to model a representative Honduran farm. With linear programming, we analyze the crop and technology mix selected by the farm given changes in distance to the output market, changes in distance to the input market, food security concerns, and labor market participation. We focus specifically on integrated pest management (IPM) technologies. Results indicate that beyond a specific distance, vegetable production ceases, while staple crop production remains profitable. Additionally, a combination of low, medium, and high-technology crop activities is selected by a profit-maximizing farm. Even far away from the market, medium and high-technology crop activities are selected. Overall, these two studies indicate that distance to market is negatively related to fruit and vegetable production. A reduction in transportation costs and an increase in the prevalence of less input-intensive integrated pest management techniques may increase the incidence of fruit and vegetable production and market participation in Trifinio and Honduras. / Master of Science

Tuta absoluta, a member of the moth family, causes devastating yield loss to tomato farmers around the world. Its recent migration into the tomato fields of Nepal puts tomato farmers at a high risk of yield loss. In response, chemical pesticide use by Nepali farmers is increasing. Integrated pest management (IPM) practices have been implemented in hopes of reducing the frequency of chemical pesticide use while controlling yield risks. This study examines the extent and determinants of Tuta absoluta IPM adoption and its effect on the frequency of pesticide use for Nepali tomato farmers. Primary data was collected from four-hundred and one households in four districts throughout Nepal. Two levels of IPM practices were assessed, simple and complex, based on the need for additional knowledge and tools. An instrumental variable probit analysis was used to analyze the determinants of IPM adoption. Household distance to nearest agricultural extension office was a significant factor decreasing the likelihood of the adoption of complex practices. Amount of land dedicated to tomato production, membership status of the primary decision maker, IPM training regarding Tuta absoluta practices and severity of Tuta absoluta were found to increase the likelihood of the adoption of complex practices. In order to analyze pesticide use, a simple linear regression was used. Primary decision maker's age, gender, and education level were significant determinates to decrease the amount of expenditures spent on chemical pesticides to control for Tuta absoluta. IPM adoption level, amount of land dedicated to tomato production and severity of Tuta absoluta damage were significant determinates to increase the amount of expenditures spent on chemical pesticides to control for Tuta absoluta. / Master of Science / Tuta absoluta, a member of the moth family, causes devastating yield loss to tomato farmers around the world. Its recent migration into the tomato fields of Nepal puts tomato farmers at a high risk of yield loss. In response, chemical pesticide use by Nepali farmers is increasing. Integrated pest management (IPM) practices have been implemented in hopes of reducing the frequency of chemical pesticide use while controlling yield risks. This study examines the extent and determinants of Tuta absoluta IPM adoption and its effect on the frequency of pesticide use for Nepali tomato farmers. Data was collected from four-hundred and one households in four districts throughout Nepal. Different economic tools were used to conduct the analyses. Results show the farther a household is to the near agricultural extension office, the less likely a household is to adopt complex practices. An increased amount of land dedicated to tomato production, the primary decision maker being a member of a marketing or community organization, the primary decision maker having attended IPM training regarding Tuta absoluta practices and the greater the severity of Tuta absoluta in the household tomato fields, the more likely a household is to adopt complex practices. Contrary to one of the goals of IPM practices, this study shows complex adopters use more chemical pesticides than simple adopters. Results this study shows a need for further education of the relationship between IPM practices and the use of chemical pesticides.

The majority of Nepal's population relies on agriculture, so invasive and native pests' ability to reduce farmers' crop yields is a significant concern. To protect farm households' food security and livelihoods, it is imperative to find effective pest management products and practices. Integrated pest management (IPM) is an arguably cheaper and less harmful alternative to conventional synthetic pesticides and is a way of managing and preventing agricultural pests using different levels of control methods (e.g., biological, cultural, and chemical) that have minimal adverse environmental and human health impacts. This study provides information on the extent of IPM practices by Nepali vegetable farmers, adds to the understanding of factors that influence the IPM adoption decision, and compares the economic benefits and performance of IPM to other conventional pest management practices. Our survey of 346 vegetable farmers in four districts throughout Nepal provides the primary data we use in our analysis. We distinguish practices into two categories: simple IPM practices that are commonly used and require limited knowledge and complex practices that typically require more knowledge and conscious use of IPM itself. We use a probit model to determine the factors that significantly affect the decision to adopt complex IPM practices. Our results find two explanatory variables that consistently affect complex IPM adoption: gender and IPM training. We compare the costs and benefits of using IPM to other conventional pest management practices by analyzing results from experimental field trials conducted in Nepal's Banke and Surkhet districts. Using an economic surplus approach, we estimate the market-level benefits of using IPM practices for three vegetables in Banke and four vegetables in Surkhet. The results predict cumulative IPM benefits of $1.06 to $1.44 million across the two districts. / Master of Science / The majority of Nepal's population relies on agriculture, so invasive and native pests' ability to reduce farmers' crop yields is a significant concern. To protect farm households' food security and livelihoods, it is imperative to find effective pest management products and practices. Integrated pest management (IPM) is an arguably cheaper and less harmful alternative to conventional synthetic pesticides and is a way of managing and preventing agricultural pests using different levels of control methods (e.g., crop rotation, weeding, pheromones to disrupt mating) that have minimal adverse environmental and human health impacts. This study provides information on the extent of IPM practices by Nepali vegetable farmers, adds to the understanding of factors that influence the IPM adoption decision, and compares the economic benefits and performance of IPM to conventional synthetic pesticides. Our survey of 346 vegetable farmers in four districts throughout Nepal provides the primary data we use in our analysis. We distinguish practices into two categories: simple IPM practices that are commonly used and require limited knowledge and complex practices that typically require more knowledge and conscious use of IPM itself. Various statistical methods are used and find that gender and IPM training consistently affect the decision to adopt complex IPM practices. Compared to female Nepali vegetable farmers, males are more likely to adopt complex practices. In addition, attending an IPM training event increases the likelihood of farmers using complex IPM practices. We use data from field trials of farmers in Surkhet and Banke, IPM adoption rates from the survey, and information on Nepal's vegetable market to calculate the economic benefits of farmers using complex IPM practices for tomato, cauliflower, onion, and cucumber production. The results predict cumulative IPM benefits of $1.06 to $1.44 million to vegetable consumers and producers across the two districts.

There is growing interest in learning the impacts of agricultural technologies especially in developing economies. Economic analysis may entail assessment of employment and time allocation effects of new technologies. An issue of importance in South Asia is the impacts of technological change on a specific type of occupation: rural non-farm activities. In order to fully understand these effects, the research must integrate gender differences and determine if the results would be similar irrespective of gender. This paper particularly looks at the effects of HYV adoption on time allocation and labor force participation of men and women in non-farm activities. In estimating the effects of HYV adoption on non-farm labor supply, information on the dependent variable, supply of non-farm labor (or the number of days worked while engaged in non-farm labor), is not available for individuals who do not participate in non-farm labor. Hence sample selection or self-selection of individuals occurs. A feasible approach to the problem of sample selection is the use of Heckman's Two Stage Selection Correction Model. Income functions were estimated for males and females while correcting for the sample selection of non-farm wage earners. An enhanced understanding of the conceptual links among HYV adoption, non-farm labor supply, and gender issues is achieved by discussing the Farm Household Model. The constrained maximization which is drawn from the Farm Household Model would bring about demand functions and reduced form functions for adoption and labor supply. The reduced-form equations are estimated at the individual level for the following: adoption of HYV technology in rice cultivation, and non-farm labor supply of both adult males and females. Regression results are presented for both Ordinary least squares (OLS) and Tobit estimates. HYV adoption and non-farm labor supply of men and women are influenced by several factors in Bangladesh. The household characteristics assumed to potentially determine technology adoption and non-farm labor decisions are the following: non-farm wages per month of the males and females, farm size, asset value, ratio of yield per decimal land of high-yielding to traditional variety of rice, HYV yield, local variety yield, and the ratio of variance of yield per decimal land of HYV to traditional or local varieties. The empirical findings suggest that the decision to adopt HYV technology is determined primarily by farm size, value of total assets of the household, ratio of yield per decimal of land of high-yielding to traditional variety of rice, and the ratio of variance of yield per decimal of land of high-yielding to traditional variety of rice. A larger farm size or land owned in decimal unit increases the non-farm labor supply of females, but not of men. HYV yield is significant and positive, while the local variety yield is significant and negative. This means that higher HYV yields increase the supply of non-farm labor of women, while higher local or traditional yields lower women's supply of non-farm labor. / Master of Science

In the promotion of Integrated Pest Management (IPM) as an alternative to pesticides, the United States Agency for International Development (USAID), the Office of International Research and Development (OIRD) at Virginia Tech, and the Caribbean Agricultural Research and Development Institute (CARDI) supported my research to uncover the socio-economic constraints to IPM adoption and to determine the amount of gendered participation in three rural Jamaica farming communities. The thesis examines the gendered participation in crop production, marketing, and decision making as well as the ability of farmers to identify key pests of three nontraditional agricultural exports: callaloo, "Scotch Bonnet" hot pepper, and sweet potato. While men generally participated to a greater extent in crop production and decision making, women also made a significant contribution. Less female participation is due in part to women owning, renting, or leasing a smaller amount of land. However, decision making about income derived from farming was found to be almost equally split between males and females. Another important finding is that women were able to identify key crop pests. To facilitate the introduction of IPM in the three communities, the small-scale farmers' limited access to irrigation and markets must be addressed. Moreover, the thesis advocates that instead of the singular focus on pest control, the holistic spirit of IPM should be seen as the catalyst for an overall integrated approach to rural farm development. / Master of Science

Orientador: Paulo Cesar Ceresini / Resumo: A adoção de cultivares de algodão Bt tem crescido nas últimas décadas devido ao aumento da disponibilidade de materiais com novas combinações de proteínas e a ocorrência de espécies de lepidópteros-pragas de difícil controle, como a Helicoverpa armigera. O objetivo deste trabalho foi verificar comparativamente a ocorrência de lepidópteros-pragas e pragas não alvo nas três cultivares Bt atualmente plantadas no Brasil: Bollgard II (Cry1Ac + Cry2Ab2), Widestrike (Cry1Ac + Cry1F) e Twinlink (Cry1Ab + Cry2Ae) e na cultivar não Bt FMT701. Para tanto, foram instalados experimento em campo e casa de vegetação. Experimento I: O delineamento empregado foi blocos casualizados com quatro tratamentos e seis repetições. Foram comparadas três cultivares de algodão Bt: Bollgard II, Widestrik e Twinlink e a cultivar não Bt FMT701. Cada parcela constou de 12 linhas com espaçamento de 0,9m com 30 m de comprimento e densidade de dez plantas/m. As avaliações foram realizadas semanalmente registrando-se a ocorrência de pragas, danos em estruturas reprodutivas e desfolha. Experimento II: Foi desenvolvido em casa de vegetação, utilizando-se as mesmas cultivares do Experimento I. Foram realizadas em cada tratamento infestações artificiais com lagartas de segundo instar da espécie H. armigera obtidas da criação em Laboratório. O delineamento foi inteiramente casualizado, com quatro tratamentos e dez repetições. Cada parcela foi constituída de uma planta de algodão, cultivado em vaso com volume de dez ... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre