Resumen

RAMIREZ-LEGARRETA, Manuel Rafael et al. Susceptibility of three apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] cultivars and management of scab [Venturia inaequalis (Cooke) Wint.] in production systems in the state of Hidalgo, Mexico. Rev. mex. fitopatol [online]. 2007, vol.25, n.2, pp.143-151. ISSN 2007-8080.

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.

Palabras llave : Fungicides; damage; forecasting; Golden Delicious; Red Delicious.