Evaluation of boxwood cultivars for resistance to boxwood blight, 2020.

Figure. Boxwood cultivars inoculated with Calonectria pseudonaviculata

Abstract

Boxwood plants worldwide are threatened by a deadly fungal disease known as boxwood blight. Twenty cultivars of boxwood were evaluated for susceptibility to boxwood blight to determine if differences in susceptibility existed. Cultivars of the most commonly used boxwood species (Buxus sempervirens) showed high levels of damage due to blight, and cultivars of species such as B. microphylla, B. harlandii and B. riparia were much less susceptible. In particular, the Japanese boxwood cultivar ‘Golden Dream’ showed no blight symptoms. This information will be used by nursery and landscape industry professionals, gardeners, and extension personnel to make informed recommendations and decisions about which boxwood cultivars to grow and use in the landscape to minimize the risk of boxwood blight.