This study evaluates the cost-effectiveness of alternative Integrated Pest Management (IPM) training methods and programs aimed at diffusing IPM innovations to farmers in Bangladesh. Various IPM innovations are categorized as being simple, intermediate or complex, while dissemination methods used to extend these innovations are classified as being less intense, moderately intense, or more intense. Examples of less intense diffusion methods include mass media and field day demonstrations, and moderately intense methods include visits from agents. A "farmer field school" (FFS) is considered a more intense type of training method. The study evaluates the effectiveness of these IPM diffusion methods based on a number of criteria such as a methods ability to reach the greatest number of farmers with a given budget, their capability of reaching farmers quickly, and their ability to influence adoption of IPM. Additional components of effectiveness include influencing appropriate use of IPM, influencing retention of IPM, providing a level knowledge that participants can adapt to other areas on the farm, and providing accessibility to limited resource farmers. Data used in the analysis come from a field survey conducted on 350 rice and vegetable farmers in Bangladesh during July and August of 2004. Three ordered probit models are used to measure adoption of simple, intermediate and complex technologies. Results from these models indicate that FFS participants are more likely than non-participants to adopt simple, intermediate and complex practices, while farmers visited by agents are more likely than non-participants to adopt simple and intermediate practices. Field day attendees are more likely to adopt intermediate and complex practices than non-participants. These results may be influenced by endogeneity of unobserved factors that influence participation in FFS but also affect adoption. The study uses a binary probit model to measure appropriate use, but it does not detect any significant differences among farmers trained through different methods, nor does it find any significant differences in retention rates among farmers who have been to different training programs. Another probit model identifies farmers who have been visited by an agent as being more likely to discover an IPM practice through their own experimentation, indicating that farmers who have been visited by an agent have received enough knowledge to adapt IPM to different problems on their farm. Results of the study indicate that limited resource farms are well represented by their participation in the various training methods, but that a higher percentage of large farmers than small farmers in the sample have been visited by an agent or been to FFS. Informal diffusion of IPM information is found to be occurring among people in FFS villages for simple practices. However, for intermediate and complex practices, farmers who participated in FFS are no more likely to spread information to other people in their villages than are less intense formal training methods such as field days and agent visits. This result indicates that while FFS graduates may be likely to share simple practices with others, they should not be relied upon as the primary means of informally diffusing more complex practices to other farmers. The cost-effectiveness estimation incorporates components of the effectiveness evaluation along with the cost of administering the methods. The study calculates that agent visits are the most cost-effective method for diffusing simple and complex technologies and practices, while field days are the most cost-effective methods for extending intermediate technologies and practices. / Master of Science

Adoption of new agricultural technologies by farmers in developing countries is sometimes limited, despite the associated benefits. Potato farmers in Carchi, Ecuador rely heavily on pesticides to limit pest and disease damage, rather than adopting a more sustainable and economically viable alternative: Integrated Pest Management (IPM). One reason IPM adoption is limited is that farmers are uncertain about the benefits of the complex technology. Information provision builds knowledge that reduces that uncertainty and leads to adoption. Another reason for limited adoption is that other farming activities compete for time, and farmers may forget or delay IPM adoption. One way to transfer information and remind farmers to adopt IPM practices is through text messages. To evaluate the impact of text messages on IPM adoption, we conducted a Randomized Control Trial (RCT) among potato farmers in Carchi, Ecuador. The RCT allowed us to identify the causal impact of text messages by comparing adoption rates and knowledge scores between farmers who received text messages (treatment), and farmers who did not (control). After attending a one-day training, the treatment received tailored IPM messages for approximately five and a half months. At the conclusion of the trial period, treatment and control farmers reported their adoption of individual IPM practices, and were tested on their IPM knowledge. Treatment farmers adopted both simple and complex practices at higher rates than the control. Farmers who received text messages also possess more knowledge about IPM techniques than non-recipients, which is evidence of the knowledge-building effect of text messages. Furthermore, text messages were shown to be effective in encouraging the adoption of practices for which no separate inputs were required, and ineffective in encouraging practices where a separate input was required. Text messages are an positive supplement to an in-person training program because they build knowledge and remind farmers, both of which encourage the adoption of IPM, which benefits the farmer, his community, and the environment. / Master of Science

An instructional guide for high school science and agricultural education courses was designed around the topic of integrated pest management (IPM) and the gypsy moth (Lymantria dispar [L.]) problem in Virginia. Construction of the guide followed three phases—design, development, and evaluation—of the Instructional Development Institute (IDI) model of instructional design. Lessons were developed using information from Virginia agricultural education course competencies, national science standards, a conceptual model of IPM, and gypsy moth management references and contacts. A validation panel consisting of two educators and two gypsy moth managers provided a review of the guide. / Master of Science

Since the 1970s Integrated Pest Management (IPM) has been promoted as an alternative to the singular reliance on pesticides to control agricultural pests. IPM involves the combination of chemical and non-chemical pest management practices to minimize pest damage to crops and reduce overall pesticide use. Although IPM has been promoted in both industrialized and Third World countries to reduce environmental and human health problems associated with pesticide use, it has not been widely adopted, particularly among small-scale farmers in the Third World. An important technical constraint to the adoption of IPM is the lack of simple, effective IPM techniques that farmers can easily incorporate into their existing farming systems. However, numerous non-technical constraints discourage farmers from adopting those IPM practices that have already been shown to be effective. Non-technical constraints to the adoption of IPM are the external political-economic forces and location-specific environmental, social and economic factors that may create obstacles to the adoption of IPM practices at the farm level. This thesis will use a political ecology approach to identify and examine the non-technical constraints to the adoption of IPM in the community of Denbigh Kraal in Jamaica. / Master of Science

While a more concentrated effort has been made in the last decade to understand the complex household behavior patterns and structures of Mali’s crop production systems and incorporate them into the prevailing research paradigms, information is still lagging in terms of knowledge related to the impacts of gender in agricultural production. This study examines the effects of resource allocation and production decisions on the attainment of food security and net revenue maximization for farmers located in the Koulikoro region of rural Mali. A linear programming model is used to determine how gender-differentiated constraints, size of the household, and potential integrated pest management (IPM) technologies could influence specific nutrient deficiencies and the ability to achieve household food security. The results suggest that IPM has the greatest potential to enhance the ability of farmers to attain higher food self-sufficiency levels by targeting women’s crop production systems. Increasing the probability of successful adoption and sustainability of natural resource management practices through IPM should positively influence food security through improved resource allocation, higher crop yields, and prevented pesticide dependency. A more thorough understanding of intra-household and community gender relations in Mali is needed so that gender-differentiated constraints can be recognized as obstacles to overcome rather than barriers to IPM adoption. / Master of Science

The twospotted spider mite, Tetranychus urticae Koch, is a serious pest of many ornamental plants (Johnson and Lyon, 1991). Pesticide resistance, the high cost of pesticides and loss of production time have raised interest by growers to introduce predatory phytoseiid mites to manage twospotted spider mites and reduce their need for acaricide applications (Sabelis, 1981). The predatory mite Phytoseiulus persimilis Athias-Henriot has been used successfully in integrated pest management programs for T. urticae suppression. Despite the success of P. persimilis in reducing populations of T. urticae, acaricide applications may still necessary due to limitations associated with the effectiveness of P. persimilis introductions. The objectives of this study were to; 1. Measure the effects of acaricides on the density and age structure of T. urticae populations. 2. Determine the compatibility of acaricides in an IPM program by measuring the toxicity of residues to P. persimilis and T. urticae adults. 3. Study the feeding behavior of P. persimilis on T. urticae. 4. Measure the effects of combinations of acaricides followed by release of P. persimilis on T. urticae populations using greenhouse trials. The effects of ten acaricides on T. urticae populations were measured on infested Buddleia x davidii 'White Profusion' cuttings. Acaricides did not alter age structure in predictable manner. Initial analysis of results demonstrates that cuttings treated with acaricides had age structures that were different from control treatments. However, these differences were not distinguishable from natural fluctuations in the age structure. Chlorfenapyr may have changed the age structure of T. urticae. Azadirachtin, pyridaben and spinosad did not suppress T. urticae populations at the rates and formulations tested in this trial. Abamectin, bifenthrin, chlorfenapyr, Gowan 1725,oil and neem oil suppressed T. urticae populations. Hexythiazox suppressed T. urticae populations but these results were not seen until two weeks after application. The effects of acaricide residues were tested on adult P. persimilis and T. urticae 1, 3, 7, and 14 days after application using a leaf disk system. Abamectin, Gowan 1725, hexythiazox, horticultural oil, neem oil, pyridaben and spionsad were not toxic to P. persimilis adults while bifenthrin and chlorfenapyr residues were toxic to P. persimilis. Tetranychus urticae mortality from chlorfenapyr residues was significantly greater than the control 1,3,7 and 14 days after application. Tetranychus urticae mortality from bifenthrin and abamectin residues was significantly greater than the control 3, 7, and 14 days after application. Tetranychus urticae mortality caused by Gowan 1725, horticultural oil, and neem oil residues was significantly greater than the control 1 day after application, while mortality from hexythiazox and spinosad residues was not significantly greater than the control at any of the times tested in this study. Phytoseiulus persimilis feeding behavior studies examining life stage preference tests and functional response studies were conducted on bean leaf disks. We found P. persimilis functional response to be a type II response for both eggs and adults with handling times of 0.079 hours for eggs and 3.399 hours for adults. The effects of a combination of acaricides followed by release of P. persimilis on T. urticae populations was tested using greenhouse studies conducted on infested Buddleia plants. In the first trial, severe plant damage occurred despite a reduction in the mean number of mites per leaf in treatments with oil+ predator treatments 7 days after release. Results from the second greenhouse trial produced plants with less visual damage compared to those in the first greenhouse trial. Treatments with predators alone and predators + acaricides produced similar results. However, treatments with predators had a mean numbers of mites per leaf that were significantly less than treatments with acaricides alone. The results demonstrate that the acaricides tested in the second greenhouse trial allowed the predators to provide suppression of T. urticae populations. A high release rate was used in the second greenhouse trial and lower release rates as well as different acaricide predator combinations need be tested to explore the possibility of new management techniques. Our results suggest that the number of pest mites present in the crop may be the most important factor affecting the success of biological control with predators. Combinations of oil applications followed by introduction of P. persimlis 3 days after release provided suppression of T. urticae populations in a meaningful time frame. I was not able to shape the age structure of T. urticae populations in a predictable manner with acaricide applications. Phytoseiulus persimilis does not have a prey-stage preference when feeding on T.urticae, but the shorter handling time for eggs may indicate that they are better able to suppress populations with higher proportions of eggs. However, we cannot determine if P. persimilis can keep T. urticae populations composed of predominately of eggs below threshold levels because our greenhouse trials did not test this hypothesis. Phytoseiulus persimilis feeding on adult T. urticae may suppress T. urticae populations below threshold levels because a reduction in the number of adults will lead to a reduction in the number of T. urticae eggs deposited on a plant. Our research suggests that abamectin and oil are two acaricides that would be less detrimental to the survival of P. persimilis. Additional greenhouse trials with compatible acaricides should be conducted as well as research on the threshold density of T. urticae that will allow P. persimilis to provide adequate control. / Master of Science

Integrated Pest Management (IPM) technologies have proven to be effective at increasing agricultural productivity and have been credited for providing economic, health, and environmental benefits in many developing countries. In South Asia, population growth and the increasing demand for nutritious foods have put pressure on farmers to produce more food with a relatively inelastic supply of land. Productivity enhancing practices, like IPM, have helped some farmers to meet this demand; however, with over 50 million farmers in Bangladesh and Nepal it is difficult to reach them with information about new agricultural technologies. This study evaluates the current IPM dissemination strategy being implemented by the Bangladesh Department of Agricultural Extension (DAE) and uses a linear programming (LP) model to propose alternative strategies that may extend the total benefits from IPM technologies. Additionally, using data from a household survey, a bivariate probit model and a two-step endogenous participation model are used to identify factors that may influence both knowledge and adoption of IPM practices in three regions of Nepal. The results from the LP model suggest that more farmers could be effectively reached by reallocating funding that is currently used for interpersonal communications (i.e. extension agent visits and farmer field schools) to more widespread methods such as mass media and field days. The model also suggests that a dynamic dissemination strategy is necessary to encourage adoption of IPM technologies with differing characteristics and levels of complexity. The econometric analysis suggests that farmers with "network linkages" to agricultural information and inputs, such as membership in a farmer organization, are more likely to be aware of IPM and to adopt IPM practices. The survey data also suggest that farmers who are members of Marketing Planning Committees (MPC) may be more likely to adopt more IPM practices when compared to non-members. Overall, the study suggests that strategically disseminating IPM information is vital to promote the adoption of these technologies in South Asia. / Master of Science

This dissertation is composed of three essays examining adoption of agricultural technologies in Ecuador and intergenerational mobility in the United States. The first essay entitled 'Does IPM Have Staying Power? Revisiting a Potato-producing Area Years After Formal Training Ended' examines (Integrated Pest Management) IPM spread and adoption several years after formal intensive IPM outreach efforts ceased in a potato-producing region in Ecuador. It describes adoption patterns and sources of IPM knowledge in 2012 and compares them with patterns that existed when outreach ceased in 2003. Results show that IPM adoption continues in the area but with a lower proportion of farmers adopting all practices and a higher proportion adopting low to moderate levels compared to 2003. Farmer-to-farmer spread has supplanted formal training and outreach mechanisms. IPM adoption significantly lowers pesticide use and saves production costs for adopters. The second essay entitled 'Can Text Messages Improve Agricultural Outreach in Ecuador?' seeks to understand how receipt of text messages complements training from a farmer field day. It measures the effect of text message receipt on adoption of (Integrated Crop Management) ICM technologies and knowledge about these technologies. In the first part of the paper, we present a theory of behavioral change and its application to adoption of agricultural technologies. In the second part, we use intention to treat (ITT) and an improved-ITT analyses to measure the impact of the intervention. The results of this essay suggest that as providers of information, text messages have some knowledge building effect leading to the adoption of IPM practices. As reminders, text messages effectively increase adoption of IPM practices, in particular recommended pesticides. The third essay entitled 'Determinants of Absolute Upward Income Mobility: The Hidden Cost of Commuting' focuses on commuting times as a determinant of upward income mobility in the United States. We provide an explanation of the channel through which the effect of commuting times on upward income mobility operates. Additionally, it evaluates empirically the effect of commuting on upward income mobility. The empirical results confirm the theoretical model predictions that commuting times affect negatively upward income mobility. / Ph. D.

This thesis analyzes factors affecting adoption of integrated pest management (IPM) techniques by Kenyan vegetable farmers, including the role of their risk preferences. It also analyzes factors affecting their pesticide applications and expenditures. A survey was administered to 450 Kenyan vegetable growers to identify their pest management practices, and a behavioral experiment was run to elicit their risk preferences utilizing. Cumulative Prospect Theory. Loss aversion was found to be correlated with higher likelihood of IPM adoption while risk aversion was associated with higher pesticide application rates and expenditures. The influence of IPM adoption on pesticide use differed by IPM technique. / Master of Science / Integrated Pest Management (IPM) techniques can improve small holder farmers' livelihoods by lowering production costs and decreasing dependence on chemical pesticides. Even though some IPM techniques have been available to Kenyan vegetable farmers since the 1990's, IPM adoption remains relatively low while chemical pesticide use remains high. A farm-household survey and behavioral experiment were conducted to identify factors that influence farmer decisions to adopt IPM and to apply pesticides. Factors that influence IPM adoption were found to differ from those that influence pesticide decisions. Furthermore, IPM adoption by Kenyan farmers does not decrease use of chemical pesticides for all IPM techniques.

Wireworms are the subterranean larval stage of click beetles (Coleoptera: Elateridae), generalist herbivores that feed on a wide range of crops and cause serious damage. Wireworm management is challenging due to their long life cycle, subterranean habitat, wide range of host plants, and lack of effective chemical approach in most crops. Thus, developing an effective alternative control approach is an urgent need. The overall aim of this research study was to evaluate alternative [to insecticides] tactics that could be used as components of effective IPM strategies against wireworms. In Chapter 1 we provide an overview of wireworm's biology and management practices. In Chapter 2 we focused on biological control to evaluate the efficacy of entomopathogenic nematodes and fungi as single and mixed application against Limonius californicus and L. infuscatus in organic vegetable farms. The results showed the higher efficacy of commercial EPN, Steinernema feltiae, against Limonius species than entomopathogenic fungi. In Chapter 3, we focused on cultural control as a component of integrated pest management for wireworm control. We evaluated the efficacy of brown and yellow mustard and their byproducts, including defatted seed meal and seed meal concentrated extract against Limonius spp. Our finding indicated the effectiveness of brown mustard concentrated extract on reducing the wireworm population. However, it has a negative impact on the field-residing entomopathogenic nematodes. In Chapter 4, in the component of cultural control, we evaluated the wireworm, L. californicus, preference to three different crops, pea, bean, and wheat, for identifying an effective trap crop. We also quantified CO2 and organic volatile compounds released from each plant's root and evaluated the wireworm response toward the synthetic volatiles. Detailed results are provided in chapter 4. Finally, we looked at the novel new technology of RNA interference to find the effective target genes in wireworms for application as bioinsecticides and/or transgenic plants to control wireworms. In the concluding chapter, Chapter 6, we summarized our findings on the efficacy of different management tactics, biological, cultural, and molecular, to control Limonius species in cereals and organic production systems. / Doctor of Philosophy / Wireworms, the larval stage of click beetles (Coleoptera: Elateridae), are belowground pests that feed on a wide range of crops such as potatoes, cereals, vegetables, and sugar beet and can cause serious economic damage. Wireworm management is challenging because they live for long periods in the soil and feed on almost all crops. Moreover, most insecticides available for wireworm control, such as neonicotinoids, are not effective in reducing wireworm populations and just serve as feeding deterrents. Thus, developing an effective alternative control approach is an urgent need. The overall aim of this research study was to evaluate alternative [to insecticides] tactics that could be used as components of effective IPM strategies against wireworms. In Chapter 1 we provide an overview of wireworm's biology and management practices. In Chapter 2 we focused on biological control to evaluate the efficacy of entomopathogenic nematodes and fungi when applied individually and in combination with each other against sugar beet wireworm in organic vegetable farms. The results showed the commercial nematode, Steinernema feltiae was more effective in reducing sugar beet wireworm than fungi. In Chapter 3, we focused on cultural control as a component of integrated pest management for wireworm control. We evaluated the efficacy of brown and yellow mustard and their byproducts including defatted seed meal and seed meal concentrated extract against sugar beet wireworms in spring wheat. Our finding indicated the effectiveness of brown mustard concentrated extract in reducing the wireworm population. In Chapter 4, in the component of cultural control, we evaluated the sugar beet wireworm preference for three different crops, pea, bean, and wheat, for identifying an effective trap crop. We also quantified CO2 and organic volaille compounds released from each plant's root and evaluated the wireworm response toward the synthetic volatiles. Detailed results are provided in chapter 4. Finally, we looked at the novel new technology of RNA interference to find the effective target genes in wireworms for application as bioinsecticides and/or transgenic plants to control wireworms. In the concluding chapter, Chapter 6, we summarized our findings on the efficacy of different management tactics, biological, cultural, and molecular, to control wireworm species in cereals and organic production systems.