Insect Mediated Species Interactions: Examining Methods to Improve Artificial Buzz Pollination and Testing the Effects of Plant Based Bioactive Compounds on Herbivore Life-history Traits

Pollination and herbivory are two major interactions in insect-plant ecology. Specialized pollination systems such as buzz pollination where pollen grains have to be extracted by bees with special thoracic vibrations and indirect flight muscles, is observed in ~6% of all flowering plants. Breeding and research programs in these species demand artificial pollination, but natural buzz pollinators are unreliable for this purpose. To find an alternative, we tested the pollen extraction efficiency of using inexpensive electric toothbrush over tuning fork (another commonly used device) in two buzz-pollinated species (Tomato and Silverleaf nightshade) at different buzzing frequencies and multiple buzzing time intervals. Our results show that species and extraction time significantly influenced pollen extraction, while there were no significant differences for the different vibration frequencies and more importantly, the use of a toothbrush over tuning fork. We conclude that electric toothbrushes can be used as a viable and inexpensive alternative to tuning forks for pollen extraction. As the second most important insect mediated species interaction, herbivory, is one of the major threats in crop production and food security. Although synthetic chemicals and pesticides are used to manage insect-pests, their use have led to major concerns of resistance development, pest resurgence as well as toxicity to non-target organisms. Plant-based bioactive compounds are good alternatives, but their use is limited by complicated and expensive extraction and purification methods. We tested the effects of polyphenol rich purple corn pericarp extract (extracted inexpensively) on the growth and development of Manduca sexta, a damaging herbivore. We found that pericarp extract negatively affects egg hatching, mass gain, developmental time and these effects cascade through pupal, adult and next generation offspring suggesting its potential suitability as a biopesticide. Taken together, our findings of inexpensive pollen extraction and sustainable pest management methods can have implications in improving agricultural practices

Light off temperature based approach to determine diesel oxidation catalyst effectiveness level and the corresponding outlet NO and NO2 characteristics

According to the latest EPA emission regulations, the NOx (Nitrogen oxide compounds) emissions from heavy duty compression ignition engines need to see a dramatic reduction. The current technology used for this purpose is the selective catalytic reduction (SCR) system, which achieves NOx reduction of around 90% [9]. This involves urea injection which is influenced by the NO: NO2 ratio at the inlet to the SCR. Thus, the role of the DOC (Diesel Oxidation Catalyst) where most of the oxidation of the NOx compounds takes place, comes to fore. The focus is also on the effectiveness of the catalyst as it thermally ages. Therefore, the aim of this research project is to correlate the aging in the DOC with the light off temperature of the catalyst and subsequent variation in the NO and NO2 concentration at the outlet of the DOC. This shall be achieved through means of a model developed after extensive experimental procedures. Also, further exhaustive experiments to validate the model over multiple aging cycles of the catalyst shall be undertaken. ^ The DOC was subjected to 2 rigorous kinds of experiments aimed at determining the light off temperature shift as the catalyst aged and to determine the NO and NO2 concentrations at the DOC outlet as it aged. Exhaust stream compounds were measured using exhaust analyzers and DOC temperatures were determined using thermocouples installed inside the DOC and at its inlet and outlet. ^ The data thus obtained was then analyzed and 2 separate models were developed, one for the light off experiments, and the other for the NOx experiments. Aging procedures were carried out at an oven according to prescribed techniques and the DOC was subjected to similar experiments again. Analysis was carried out on the data. From the light off experiments and the model analysis, a clear positive shift in light off temperatures was observed from one aging level to another across the range of set points. It was also observed that even after subjecting the DOC to three thermal aging exercises, its conversion efficiency went up to 90%. Also, as the DOC aged, the NO concentration at the DOC outlet showed a downward trend which was observed across the spectrum of engine set points and aging levels. These experiments were repeated for consistency so that the models could be rendered more useful

Post-harvest innovation systems in South Asia: key features and implications for capacity development

Post-harvest research and development (R&D) offers the potential to support the livelihoods of poor people in developing countries as: farmers, small-scale agro processing entrepreneurs, off-farm laborers, and consumers of food and agricultural products. It is increasingly recognized, however, that efforts to strengthen post-harvest systems in developing countries will need to pay much greater attention to the institutional environment in which change takes place (Hall et al. 2002a). This institutional environment does not just concern the organizations involved, but more importantly the norms, routines, and rules that govern the way organizations operate and interact with each other. Keywords: Post-harvest R&D, [IDE(I)], Institutional innovation, HORTICULTURE TECHNOLOGY R&D, Agricultural Research.

Post-harvest innovation systems in South Asia: key features and implications for capacity development

Post-harvest research and development (R&D) offers the potential to support the livelihoods of poor people in developing countries as: farmers, small-scale agro processing entrepreneurs, off-farm laborers, and consumers of food and agricultural products. It is increasingly recognized, however, that efforts to strengthen post-harvest systems in developing countries will need to pay much greater attention to the institutional environment in which change takes place (Hall et al. 2002a). This institutional environment does not just concern the organizations involved, but more importantly the norms, routines, and rules that govern the way organizations operate and interact with each other. Keywords: Post-harvest R&D, [IDE(I)], Institutional innovation, HORTICULTURE TECHNOLOGY R&D, Agricultural Research.