This paper explores hidden problems amid the impressive expansion of farmers' markets in Oregon and throughout the United States. Although markets are growing in number, a surprisingly large number of them fail. A challenge for many markets is inadequate revenue to support market operations such as paying for the management personnel to perform functions necessary to grow and sustain markets. Smaller markets may enter a downward spiral in which they cannot attract additional customers because they do not have sufficient vendors but cannot attract additional vendors because they do not have sufficient customers. The analysis identifies five intertwined factors associated with markets that fail: small size, a high need for products, low administrative revenue, a volunteer or low paid manager and high manager turnover. The paper also examines the more general issue of why some markets struggle by exploring a correlation between new markets and inexperienced managers, and effort thresholds for volunteer managers. Recommendations to assist markets toward success include better planning, manager and board of director training and community financial support. The findings of this study have broad application.
Drosophila suzukii (Matsumura) is a vinegar fly species that originates from Eastern Asia and has spread throughout Europe and the Americas since its initial detection in United States in 2008. Its relatively large, sclerotized, and serrated ovipositor enables the ability to penetrate ripening fruits, providing a protected environment for its egg and larval stages. Because the mechanism of oviposition site selection of D. suzukii is a matter of hypothesis, the aim of the present study was to elucidate behavioral and chemical aspects of short-range ovipositional site selection within the context of D. suzukii reproductive biology. The preference of D. suzukii to lay eggs on artificially pierced, previously infested, or intact fruits was tested. Video recordings and photographic evidence documented the release of an anal secretion over the fruit surface near the oviposition sites. Gas chromatographic analysis revealed the presence of 11 compounds detected only on the skin of egg-infested berries. Electroantennographic experiments with both sexes of D. suzukii highlighted the importance of six volatile compounds: methyl myristate, methyl palmitate, myristic acid, lauric acid, palmitic acid, and palmitoleic acid. Finally, a synthetic blend composed of the six compounds in a ratio similar to that found on the skin of egg-infested berries increased the oviposition rate of conspecific females. Data from our work suggest that the identified volatiles are cues for reproductive site selection. We discuss how these oviposition cues may affect the fitness of D. suzukii. The knowledge gained from this study may accelerate establishment of control strategies based on the interference and disruption of D. suzukii communication during the oviposition processes.
BACKGROUND Insecticide applications in blueberry production systems play a crucial role in the control of Drosophila suzukii populations. Here, quantitative spray deposition patterns were obtained under replicated field experiments in blueberry during two field seasons with three sprayers, i.e. cannon, electrostatic, and air‐blast. Seven insecticides were tested (at 6 hours using a Potter spray tower) to determine the mortality data for adult D. suzukii. Spray deposition and mortality data for adult D. suzukii were used to create model simulations for insect populations. Model simulations included field deposition rates of sprayers and insecticide mortality as factors. Simulations were applied in different combinations with five applications over a 6‐week period. RESULTS Relative deposition rates for the cannon sprayer were elevated in the upper zones of the canopy, whereas for the air‐blast sprayer, deposition was greater in the bottom zones. Electrostatic spray deposition was relatively uniform within the six canopy zones. Clear trends in D. suzukii laboratory mortality were found with lowest to highest mortality recorded for phosmet, spinetoram, spinosad, malathion, cyantraniliprole, zeta‐cypermethrin, and methomyl respectively. Maximum D. suzukii population impacts, as shown by model outputs, were observed with air‐blast sprayers together with zeta‐cypermethrin. CONCLUSION The electrostatic sprayer had the least variable canopy deposition among the three types of spray equipment, and the air‐blast sprayer had the highest overall deposition rates. This study provides new hypotheses that can be used for field verification with these spray technologies and insecticides as key factors. © 2019 Society of Chemical Industry
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