No abstract

Abstract. The extracts of wild grapevines (Vitis) leaves (EHVS) from three accessions (P-178, E-200 and TN-4) at 6, 8 and 12 % v/v, were tested in vitro to evaluate their inhibitory effect on Botrytis cinerea development. Resveratrol (RVS) (60, 90, 120 µg/mL), citrus extracts (EC) (3, 5 and 8 % v/v) and cyprodinil + fludioxonil (SW) (500, 800 and 1000 µg/mL) were compared against EHVS. In average, SW presented inhibition of mycelial growth (ICM), sporulation (IE) and spore germination (IGC) (88.9; 85.5 and 93.7 %, average respectively). RVS presented the second higher inhibition rate. All EHVS presented antifungal activity; specially, P-178 at 12 % resulted in 72 % ICM, 75 % IE and 62 % IGC. This dose contained phenolic compounds 19.9 mg/mL, RVS 1.7 mg/mL, gallic acid 3.8 mg/mL and ferulic acid 2.5 mg/mL.

Resumen. La cenicilla del rosal causada por Podosphaera pannosa afecta todas las partes aéreas de la planta, lo que repercute en su calidad como principal componente de la pérdida económica. En el presente trabajo, se confirmó la identidad del agente causal de la cenicilla en rosa y se evaluó el efecto del fosfito de potasio (K 3 PO 3 ), silicio, quitosano y acetato de dodemorf sobre la incidencia y severidad de la enfermedad, así como, su respuesta en la calidad de tallos florales. Se realizaron dos ensayos (febrero-abril y mayo-julio). Las caracterís-ticas morfométricas y moleculares del agente causal de la cenicilla correspondieron a Podosphaera pannosa. El K 3 PO 3 , silicio y quitosano redujeron Abstract. Rose powdery mildew caused byPodosphaera pannosa affects all aerial parts of the plant, which affects their quality as a major component of economic loss. In this work, the causal agent of powdery mildew of rose was identity and confirmed, the effect of potassium phosphite (K 3 PO 3 ), silicon, chitosan and dodemorph acetate on the incidence and severity of the disease was evaluated, as well as their response in the quality of flower stalks. Two trials (February to April and from May to July) were performed. The morphometric and molecular characteristics of the causal agent corresponded to Podosphaera pannosa. The K 3 PO 3 , silicon and chitosan they reduced incidence and severity compared to the control for both assays, however, only the K 3 PO 3 and silicon, exhibited a control similar to provided by the fungicide dodemorph acetate. The treatment with chitosan increased the length and diameter of the stem and flower bud in contrast to K 3 PO 3 and silicon, but was not significant to the control in both tests. Based on the results, the K 3 PO 3 , silicon and

Worldwide, there are a large number of retailers in popular markets offering fresh orange juice, which is preferred for its nutritional and health value. Incorrect management during the preparation, the presence of pests, and inadequate environmental conditions can affect the microbiological quality of the juices sold in popular markets and can even make them a reservoir for enteropathogenic bacteria. The aim of this study was to evaluate the microbiological quality and presence of enteropathogenic bacteria in freshly prepared orange juice sold in popular markets, by quantifying the fungi, yeasts, aerobic mesophilic bacteria, and total and fecal coliforms. The fecal colonies were subjected to tests to confirm the presence of enteropathogenic bacteria. The results showed that none of the juice sold at popular markets had fungi, while all of them had yeasts, mesophilic bacteria, and total coliforms, and only 14% did not present fecal coliforms. The identification of the fecal bacteria was positive for E. coli and Salmonella. The microbiological quality of the orange juices sold in popular markets needs to be improved, since the high microbial load makes them a health risk.

El mildiu velloso causado por Peronospora sparsa Berkeley es una de las enfermedades más importantes del rosal en México, causando pérdidas de 100%. Su manejo se basa con fungicidas en continuas aplicaciones que tienden a generar poblaciones resistentes. La búsqueda de alternativas es indispensable. En el presente trabajo se confirmó la identidad morfométrica y molecular del agente asociado con el mildiu del rosal, se evaluó la eficacia del fosfito de potasio (K3PO3), quitosano, silicio y mefenoxam para el manejo de la enfermedad y se determinó su efecto en la longitud y diámetro de tallo floral. El estudio se realizó en verano y otoño de 2013 en Tenancingo, Estado de México. La caracterización morfométrica se realizó bajo microscopio compuesto y electrónico de barrido. Para la caracterización molecular, se amplificó el ADN ribosomal de la región ITS con los primers PS3 y PS1. Los tratamientos fueron: fosfito de potasio (K3PO3), quitosano, silicio, mefenoxam y testigo y se aplicaron a intervalos semanales. El diseño experimental fue de bloques al azar y la comparación de medias fue por Tukey (α= 0.05). Datos morfométricos y moleculares correspondieron a Peronospora sparsa. El K3PO3 y silicio redujeron la incidencia y severidad con respecto al testigo. El tratamiento con K3PO3 mostró incrementos de 24.8 y 97.5% en la longitud de tallos con diámetros de 7.5 y 6.2 mm en verano y otoño respectivamente, comparando con el testigo. Así, el K3PO3 y silicio pueden ser alternativas en el manejo del mildiu velloso del rosal en condiciones de invernadero.