Susceptibility of novel Italian rice varieties to panicle blast under field conditions

Abstract

A panel of 48 of Italian rice varieties recently included in the Common Catalogue of Agricultural Species was evaluated for susceptibility to rice blast (Magnaporthe oryzae B. Couch) in open field conditions. Trials were performed under highly favourable conditions for the pathogen, and visual assessments focused on the severity and incidence of panicle blast symptoms. Only 8% of newly released varieties were classified as resistant, whereas 40% were highly susceptible. Our results confirmed that a fungicide treatment with tricyclazole reduces the disease incidence and severity and that the effect is measurable up to six weeks after treatment. A double application of tricyclazole at stem elongation and booting stage was more effective than the single application at booting. This study provides ready-to-use information to support rice growers in variety choice and planning of plant protection strategies, as well as public institutions in the emanation of guidelines for integrated pest management.