Ellen Reynolds

© 2016 Public Library of Science. All rights reserved.Black Sigatoka or black leaf streak disease, caused by the Dothideomycete fungus Pseudocercospora fijiensis, is the most significant foliar disease of banana worldwide. Due to the lack of effective host resistance, management of this disease requires frequent fungicide applications, which greatly increase the economic and environmental costs to produce banana. Weekly applications in most banana plantations lead to rapid evolution of fungicide-resistant strains within populations causing disease-control failures throughout the world. Given its extremely high economic importance, two strains of P. fijiensis were sequenced and assembled with the aid of a new genetic linkage map. The 74-Mb genome of P. fijiensis is massively expanded by LTR retrotransposons, making it the largest genome within the Dothideomycetes. Melting-curve assays suggest that the genomes of two closely related members of the Sigatoka disease complex, P. eumusae and P. musae, also are expanded. Electrophoretic karyotyping and analyses of molecular markers in P. fijiensis field populations showed chromosome-length polymorphisms and high genetic diversity. Genetic differentiation was also detected using neutral markers, suggesting strong selection with limited gene flow at the studied geographic scale. Frequencies of fungicide resistance in fungicide-treated plantations were much higher than those in untreated wild-type P. fijiensis populations. A homologue of the Cladosporium fulvum Avr4 effector, PfAvr4, was identified in the P. fijiensis genome. Infiltration of the purified PfAVR4 protein into leaves of the resistant banana variety Calcutta 4 resulted in a hypersensitive-like response. This result suggests that Calcutta 4 could carry an unknown resistance gene recognizing PfAVR4. Besides adding to our understanding of the overall Dothideomycete genome structures, the P. fijiensis genome will aid in developing fungicide treatment schedules to combat this pathogen and in improving the efficiency of banana breeding programs.

Diverse legal and regulatory measures are used internationally to control the information provided during pharmaceutical sales visits. Little is known about the comparative effectiveness of these measures however. We analyzed the perceptions of regulators, pharmaceutical industry officials, health professionals, and consumer respondents concerning these approaches in Canada, France, and the United States using an empirical realist interests-based approach. Interviews focused on the aims and effectiveness of regulation, barriers and enablers to regulation and suggestions for improvement. An alignment was found in North America regulator and industry respondents' satisfaction with the status quo and their view that further intervention is unfeasible and unnecessary. Health professionals generally expressed a lack of confidence in the impact of regulations on sales visit information while consumer advocates voiced their disappointment in both regulators and health professionals for their failure to counteract the influence of pharmaceutical marketing. Regulator and industry respondents in France differed from their North American counterparts in their willingness to increase and diversify the scope of regulatory interventions. As the first international comparison of regulatory experiences in this sector, the findings highlight the universal need for more focused and inclusive discussions among groups about how to tailor regulations to achieve public health goals.