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This study aimed to characterize the quality and bioactive compounds from five cultivars grown in Mexico´s northern region: Heritage, Summit, Harvest, and red and yellow Autumn. The physicochemical characteristics, DPPH anti-radical capacity, total phenolics, flavonoid and anthocyanins, polyphenolic profile, and ascorbic acid levels of the raspberries were assessed. The Harvest cultivar presented the highest weight and firmness and the lowest yield, total phenolics, and flavonoids. The yellow Autumn Bliss contained higher concentrations of polyphenols and ascorbic acid, and the red Autumn Bliss contained higher concentrations of flavonoids and anthocyanins and possessed a greater antioxidant capacity. The polyphenol profile indicated the presence of seven phenolic acids, namely, ellagic, gallic, caffeic, chlorogenic, p-coumaric, hydroxybenzoic, and protocatechuic acids; and four flavonoids, namely, catechin, quercetin-3-β-D-glucoside, quercetin-3-glucuronide, and rutin; these compounds were present in all the varieties, except for rutin, in yellow Autumn Bliss. The results of this study highlight the most valuable raspberry cultivars in terms of weight and firmness (Harvest), yield (Heritage), polyphenols and ascorbic acid (yellow Autumn Bliss), and anthocyanins and antioxidant capacity (red Autumn Bliss) in raspberries grown in northern Mexico. [ABSTRACT FROM AUTHOR]

Despite efforts to prevent microbial contamination, the occurrence of human pathogens in fresh fruit and vegetable is quite common. It is now known that E. coli O157:H7 can inhabit food plants passively. Here, we review the literature on phylloplane adhesion, survival and internalization of this bacterium, as well as some of the interaction mechanisms between it and the food plant, and other associated microorganisms. This pathogen, once it has adhered to the surface of a food plant, can then enter the plant tissues, where it can migrate within them, and even multiply. This review provides an overview of the interaction mechanisms between the food plant tissues and E. coli O157:H7. It finds that this pathogen has improved its ecological competence in food plants without losing its virulence to humans. Also, a number of future research areas were identified. [ABSTRACT FROM AUTHOR]

Dynamics of flower bud development in apple trees cvs. Red Delicious (RD) and Golden Delicious (GD) was monitored in 1996, 1997, and 1998. The phenological stages evaluated were: eco-dormant, green tip, half-inch green, tight cluster, full pink, bloom, petal fall, and fruit set. Sample size varied from 330 to 556 buds. Data analysis was done by a Weibull distribution, and a time scale expressed as thermic units (UT) was used, considering a threshold of 7°C. Results indicate that the period from initial break to bloom required 354 ± 33 UT in RD and 431 ± 45 UT in GD. The bloom stage lasted for 106 ± 9 UT in Rd and 187 ± 45 UT in GD. The budbreak process in RD started on March 15, 1996, March 13, 1998, and on March 19 in 1999; while for GD started on April 1, March 24 and 30 in the same years. Weather data showed that winter quality decreased in a continuous fashion from 1992 to 1999. [ABSTRACT FROM AUTHOR]

The susceptibility to scab under natural conditions of three apple cultivars, as well as the effectiveness of Mills Table for fungicide utilization to manage the disease were evaluated during 2005-2006 in Acaxochitlan, Hidalgo state, Mexico. Scab damage on the three cultivars was quantified on leaves and fruits of 15 trees under the prediction system management and 15 trees under the traditional farmer management. Maximum and minimum temperatures, as well as rainfall and periods of humidity were recorded. Golden Delicious was the most susceptible cultivar, followed by Red Delicious and the regional cultivar Rayada. In 2005-2006 under the traditional system, Golden Delicious showed an average of 26.4 lesions per leaf and 83.8 lesions per fruit, while Red Delicious and Rayada showed 13.7 and 27.3, and 4.2 and 0.6, respectively. Under the prediction system Golden Delicious under showed an average of 3.2 lesions per leaf and 0.4 per fruit, while Red Delicious and Rayada showed 1.8 and 0.4, and 0.7 and 0, respectively. Dissemination of the inoculum (ascospores and conidia) was recorded from march to august. [ABSTRACT FROM AUTHOR]