Beet Moth: Has Summer 2022 Introduced a New Threat to the UK Sugar Beet Crop?

Abstract

When the first samples of ‘beet black heart’ arrived at the BBRO Plant Clinic in May 2022, the initial reaction was that it was due to downy mildew or boron deficiency, but as the long hot summer continued it became increasingly apparent some of these early samples were more likely to have been the first signs of beet moth damage. Although not a new problem (several isolated cases were recorded in commercial beet during 2020), the extent of the issue and the widespread impact on the crop took many by surprise. In this article we highlight some of the challenges caused by this pest and reflect on what the industry can do to limit its impact in the future. The beet moth (Scrobipalpa ocellatella) is not regarded as a regular pest in the UK, but adult moths are trapped and reported by UK entomologists. It is known to be more problematic in Mediterranean areas and across Eastern Europe/Asia where its incidence and reports of damage are usually associated with warmer and drier climates. Unfortunately, to date, we have limited information on its life cycle in relation to UK conditions and our sugar beet crops.