First report of QoI resistance in Alternaria spp. infecting sugar beet (Beta vulgaris)

摘要

Alternaria leaf spot (ALS) of sugar beet (Beta vulgaris), caused by Alternaria spp. in the A. alternata and tenuis species-group, is common wherever sugar beet is grown (Franc, 2009). Historically, Alternaria spp. infection and disease management has been a minor issue in the USA due to its opportunistic or secondary nature, and normally, ALS does not significantly affect yield (Franc, 2009). The occurrence of ALS is a concern in some sugar beet production areas outside the USA including parts of Europe (Özgönen & Kilic?, 2009), as the reduction of photosynthetic area from leaf spot infection (starting at 5%) results in significant reductions in sugar yield (Wolf & Verreet, 2002).