In an article 'Characterization and taxonomic reassessment of the box blight pathogen Calonectria pseudonaviculata, introducing Calonectria henricotiae sp. Nov', published in the Plant Pathology journal, nine academics found the identification of a second phylogenetic species causing box blight "may have a substantial impact on the epidemiology and control of the disease".
Calonectria pseudonaviculata, the causal agent of the disease of Buxus was first detected in the mid 1990s in the UK and New Zealand.
Since then, the geographic range of box blight has rapidly expanded to at least 21 countries throughout temperate regions of the world, causing significant losses in nurseries, gardens and wild boxwood populations.
The authors determined the genetic diversity in a collection of 234 Calonectria isolates from diseased Buxus plants, originating from 15 countries and four continents. Two genetic clades, G1 and G2, were identified within this sample using multilocus phylogenetic analysis. The application of Genealogical Concordance Phylogenetic Species Recognition (GCPSR) criteria using four independent nuclear loci and the identification of a second phylogenetic species causing box blight may have a impact on the control of this disease.