Within‐ and between‐orchard variability in the sensitivity of Venturia inaequalis to myclobutanil, a DMI fungicide, in the UK

Abstract

Spatial spread of insensitive isolates of V. inaequalis to myclobutanil is likely to be limited in distance. Conidia may be an important source of primary inoculum. Myclobutanil should still be effective for most field isolates, but its use should be strategically integrated with other groups of fungicides.

A sterol 14α-demethylase is required for conidiation, virulence and for mediating sensitivity to sterol demethylation inhibitors by the rice blast fungus Magnaporthe oryzae

“…DMI fungicides have been widely used in medicine and agriculture and constitute some of the most successful fungicides. However, resistance to DMIs has now been reported in many fungal species (Hildebrand et al, 1988;Delye et al, 1998;Ma et al, 2006;Leroux et al, 2007;Gao et al, 2009;Sombardier et al, 2010), and the molecular mechanism leading to DMI resistance has been investigated in several plant pathogenic species, including Blumeriella jaapii Proffer et al, 2006), Blumeria graminis (Delye et al, 1998;Wyand and Brown, 2005), Monilinia fructicola (Luo and Schnabel, 2008), Mycosphaerella graminicola (Leroux et al, 2007;Brunner et al, 2008;Bean et al, 2009), Mycosphaerella fijiensis (Canas-Gutierrez et al, 2009), Penicillium digitatum (Nakaune et al, 1998;Hamamoto et al, 2001;Zhao et al, 2007), Tapesia yallundae (Wood et al, 2001), Venturia inaequalis (Schnabel and Jones, 2001), Fusarium asiaticum and Fusarium graminearum (Yin et al, 2009). Currently, the DMI fungicides, such as propiconazole, are widely used for the control of rice blast disease (Skamnioti and Gurr, 2009).…”

One hundred years of research at East Malling: science into practice for perennial fruit crops

“…Studies of the epidemiology of V. inaequalis (Jeger et al ., ) led to the development of mathematical models of the infection process and prediction of epidemics, which together with other disease and pest risk models, was developed into a grower friendly computer‐based forecasting system known as ADEM (Xu & Butt, ). More recent work on V. inaequalis has monitored the emergence of fungicide resistance (Gao et al ., ; Xu et al ., ) and virulence characteristics of V. inaequalis populations (Jeger, ; Barbara et al ., ; Xu et al ., ).…”

The relative importance of conidia and ascospores as primary inoculum of Venturia inaequalis in a southeast England orchard

“…Studies (Holb et al ., , ; Gao et al ., ) suggest that conidial sources may be a significant part of the primary inoculum. This is important because reduction of overwintering inoculum and early season control measures differ for the two sources of inoculum.…”