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The aim of this study was to design and validate a diagrammatic scale to estimate the severity of gray mold induced by Botrytis cinerea in pomegranate cultivation. A total of 120 healthy and diseased fruits with varying degrees of affliction were collected from orchards with active production located in the municipalities of Chilcuahutla and Taxquillo in the state of Hidalgo, Mexico (20° 18' 11" N, 99° 14' 23" W, 20° 32' 01" N, 99° 20' 03" W, respectively). From these, 60 were selected to determine the severity percentage, according to a 6-class scale (Class 0 = 0%, Class 1 = >0% - 5% - 10%, Class 2 = >10% - 25% - 50%, Class 3 = >50% - 75% - 85%, Class 4 = >85% - 90% - 95%, and Class 5 = >95% - 100%), using the 2LOG software. With the obtained data, representative images were selected to build the diagrammatic scale using Adobe Photoshop. The accuracy (r2), precision (ß0), and reproducibility (ß1) were verified by simple linear regression applied to the data obtained by 12 evaluators with and without experience in the observation of plant diseases. As a result, values of r2 of 0.42 and 0.85 were obtained, without and with the use of the scale, respectively, which confirmed that this tool is suitable to evaluate the severity of the disease accurately and reproducibly. [ABSTRACT FROM AUTHOR]

Cheesemaking is one of the most important industries in Mexico. Among all the Mexican cheeses, fresh cheeses are the most popular and most consumed cheese in Mexico and Latin America. However, in Mexico fresh cheese is frequently made with unpasteurized milk and sold in public markets. This may increase the risk for contamination of dairy products with pathogenic bacteria. The presence of multidrug-resistant pathogenic bacteria in food is an important public health concern. Diarrheagenic Escherichia coli pathotypes (DEPs) are foodborne bacteria. This study investigated the presence of indicator bacteria and multidrug-resistant DEPs in fresh cheeses. A total of 120 fresh cheese samples were collected from public markets in the city of Pachuca, Mexico. The samples were analyzed for presence of fecal coliforms (FC), E. coli, and antibiotic resistant DEPs. FC and E. coli were analyzed using the most-probable-number technique. DEPs were identified using two multiplex PCR methods. Susceptibility to 16 antibiotics was tested for the isolated DEPs strains by the standard assay. The frequency of FC, E. coli, and DEPs in the cheese samples was 50, 40, and 19%, respectively. The identified DEPs included Shiga toxin–producing E. coli (STEC; 8%), enteropathogenic E. coli (EPEC; 6%), and enterotoxigenic E. coli (ETEC; 5%). All isolated strains exhibited resistance to at least five antibiotics. One, one, two, and three STEC strains were resistant to 14, 12, 11, and 10 antibiotics, respectively. One strain of EPEC was resistant to 11 antibiotics, three EPEC strains to 9, and one strain to 7. One, one, and two strains of ETEC were resistant to 10, 8, and 7 antibiotics, respectively. The results of the present study indicate that fresh cheeses made with unpasteurized milk could be a risk for consumers, both for native people and visitors to Mexico. [ABSTRACT FROM AUTHOR]