10 research outputs found
Video-tracking and On-plant Tests Show Cry1Ab Resistance Influences Behavior and Survival of Neonate Ostrinia nubilalis Following Exposure to Bt Maize
To examine how resistance to Bacillus thuringiensis (Bt) toxins influences movement and survival of European corn borer (Ostrinia nubilalis [Hübner]) neonates, the responses of Cry1Ab-resistant , -susceptible, and hybrid (F1) larvae were examined using two different techniques. First, using an automated video-tracking system, aspects of O. nubilalis movement were quantified in the presence of artificial diet incorporating 50% non-Bt or insect-resistant Cry1Ab maize tissue. Second, O. nubilalis dispersal and survival were measured 48–72 h after hatching on a Cry1Ab maize plant surrounded by two non-Bt maize plants. Video tracking indicated the presence of Cry1Ab tissue increased the total distance moved (m), time moving (%), and time away from the diet (%) for O. nubilalis while decreasing meander (degrees/cm). However, resistant larvae showed reduced movement and increased meander (≈localized searching) relative to susceptible or hybrid larvae on diet incorporating Cry1Ab tissue. Conversely, when placed onto Cry1Ab maize plants, resistant larvae were more likely than susceptible O. nubilalis to disperse onto adjacent non-Bt plants. The difference in on-plant dispersal seems to reflect greater survival after toxin exposure for resistant larvae rather than increased activity. These results suggest that simplified ‘Petri dish’ tests may not be predictive of larval movement among non-Bt and insect-resistant Bt maize plants. Because models of O. nubilalis resistance evolution incorporate various movement and survival parameters, improved data for on-plant behavior and survival of Bt- resistant , -susceptible, and hybrid larvae should help preserve the efficacy of transgenic insect-resistant maize
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Entrepreneurial networks and women entrepreneurship: a social feminist perspective of social capital
This study utilizes a social feminist perspective of social capital to investigate how entrepreneurial networks influence women’s entrepreneurship in developing economies. To this purpose, we collected and analyzed rich data generated through in-depth interviews and artifacts of Nigerian women entrepreneurs and key stakeholders. The qualitative data were thematically analyzed using the phenomenological approach to data analysis. Our findings revealed that entrepreneurial networks are mediums through which women entrepreneurs gain access to financial and physical resources, human resource development, and social and external support opportunities for customer attraction and retention. Our analysis therefore suggests that in developing countries, characterised by a weak or non-existent entrepreneurship ecosystem, entrepreneurial networks represent a medium that could fill the voids created by a weak institutional environment. This article contributes to women entrepreneurship literature by revising a male-based perspective of entrepreneurial networks into a gender-sensitive field