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One of the main problems in the production of cacao in Ecuador is the disease caused by the fungus Moniliophthora roreri (frosty pod rot) which affects the pods. Here, we evaluate the genetic diversity of this fungus in Ecuador, and its sensitivity to the fungicide azoxystrobin. We evaluated 76 monosporic cultures from the Amazon and the Pacific coast regions. In vitro sensitivity assays tested several doses of the fungicide azoxystrobin to determine the percent of growth inhibition and the IC50. Concentrations of 1 to 0.1 µg mL−1 inhibited the growth of at least 91% of the isolates. Three isolates were the less sensitive (IC50 = 0.0220–0.0364 µg mL−1), two from Guayas (Pacific coast) and one from Sucumbíos (Amazon) provinces. However, M. roreri is highly sensitive, and it could be used in integrated management of the disease. Genetic analyses were carried out by amplifying microsatellite markers (SSR). All the genetic diversity statistics show a higher diversity in the Amazon compared to samples of the coast region; however, the molecular variance was low (FST = 0.11). Discriminant analysis clearly distinguishes three clusters concurrent with the provinces (Sucumbíos, Orellana and El Oro) and a group with the rest of the provinces. Minimum spanning networks shows, unexpectedly, that M. roreri from the coast were derived from at least three independent introductions from the Amazon. Findings are discussed in light of previous Pan-American genetic studies and available historical reports.

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Biosurfactants (BS) are amphiphilic molecules that align at the interface reducing the surface tension. BS production is developed as an alternative to synthetic surfactants because they are biodegradable, with low toxicity and high specificity. BS are versatile, and this research proposes using a biosurfactant crude extract (BCE) as part of cleaning products. This paper reported the BCE production from Bacillus subtilis DS03 using a medium with molasses. The BCE product was characterized by different physical and chemical tests under a wide pH range, high temperatures, and emulsifying properties showing successful results. The water surface tension of 72 mN/m was reduced to 34 mN/m with BCE, achieving a critical micelle concentration at 24.66 ppm. BCE was also applied to polystyrene surface as pre-treatment to avoid microbial biofilm development, showing inhibition in more than 90% of Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes above 2000 ppm BCE. The test continued using BCE as post-treatment to remove biofilms, reporting a significant reduction of 50.10% Escherichia coli, 55.77% Staphylococcus aureus, and 59.44% Listeria monocytogenes in a concentration higher than 250 ppm BCE. Finally, a comparison experiment was performed between sodium lauryl ether sulfate (SLES) and BCE (included in commercial formulation), reporting an efficient reduction with the mixtures. The results suggested that BCE is a promising ingredient for cleaning formulations with applications in industrial food applications.