Why do people participate in Web surveys? Applying survey participation theory to Internet survey data collection

In recent years Web surveys have emerged as the most popular mode of primary data collection in market and social research. To improve our understanding about the influence of different societal-level factors, characteristics of the sample person, and attributes of the survey design on participation in Web surveys, this paper establishes a systematic link between theoretical frameworks used to explain survey participation behavior and state-of-the-art empirical research on online data collection methods. The concepts of self-perception, cognitive dissonance, commitment and involvement, social exchange, compliance, leverage-salience, and planned behavior are discussed and their relationship with factors that have empirically proven to influence Web survey participation are analyzed using data from an expert survey. This paper will help researchers and practitioners to make informed decisions about the use of techniques increasing participation in Web surveys

Genetics and Genomics of Carrot Biotic Stress

International audienceCarrot (Daucus carota ssp. sativus) production can be affected by a wide range of pests and pathogens. At least five diseases of carrot are caused by bacterial pathogens, 36 by fungal and oomycete pathogens, two by phytoplasmas, and 13 by viruses; and seven genera of nematodes and two genera of parasitic plants affect carrot. In addition, numerous insect and mite pests can cause losses. There have been extensive efforts to select carrot cultivars with partial or complete resistance to many of these pathogens and pests, and to identify wild species with resistance to specific biotic stresses for introgression into breeding populations and commercial cultivars. For some pathogens and pests, significant advances have been made at identifying resistance and mapping that resistance to the carrot genome. For others, resistance has been identified, but the genetic basis is yet to be determined. For a majority of these diverse stresses, however, there has been little success at identifying highly effective resistance and understanding the genetic basis of resistance. The diversity of stresses as well as interactions among these pests and pathogens can complicate efforts to develop cultivars with resistance to all key biotic stresses in a region that also meet market and consumer expectations. New approaches to identifying resistant material and speeding traditional breeding are being developed with molecular breeding tools, including simple sequence repeat markers and deep-coverage libraries of the carrot genome. These valuable genomic resources will enhance efforts to identify and breed for resistance to carrot pests and pathogens