Integrated fungal foliar disease management of sugar beet

Compton, Angharad

Integrated fungal foliar disease management of sugar beet

Publication Date

July 27, 2026

Creator

Compton, Angharad

University of Nottingham, UK

Abstract

The fungal foliar diseases, rust (Uromyces beticola), cercospora (Cercospora beticola) and powdery mildew (Erysiphe betae) pose a major threat to UK sugar beet production resulting in foliar damage and reduction of photosynthetic capacity, ultimately leading to yield losses. Integrated pest management strategies (IPM) aim to control these pathogens while minimising unnecessary fungicide application. Through a combination of field trials and inoculated glasshouse experiments, this study evaluates the efficacy of several IPM approaches for controlling rust and cercospora. Specifically, the research investigates the potential of varietal mixtures, specifically alternating rows of resistance and susceptible varieties, for fungal foliar disease control of sugar beet. This thesis also considered the efficacy of fungicide control of rust and cercospora whilst increasing the application interval of two-spray fungicide programs across varieties of varying disease resistance, in order to determine whether fungicide control could be extended without additional applications, thus reducing fungicide requirement. Additionally, the potential use of spectral vegetation indices derived from remote and proximal sensing to detect and monitor presymptomatic disease infection was assessed. The results demonstrated that alternating rows of BTS 5770 (resistant) and Evalotta (susceptible) was an effective means for rust and cercospora control and may allow for mitigation of yield penalties associated with resistant varieties. This study found that the fungicide application interval may be extended from 28-days to 58-days without increasing rust and cercospora severity. Additionally, in some cases a single-spray program was more economically viable than a two-spray program. The SVIs CRI, PSSRc, EVI and MCARI, derived from ASD FieldSpec 4 Hi-Res: High Resolution spectroradiometer show potential for use in non-destructive presymptomatic detection of cercospora in sugar beet. Overall, these findings highlight the use of alternating row treatments and optimisation of fungicide applications timing for control of rust and cercospora as part of a wider sugar beet IPM strategy. In addition, SVIs show potential for presymptomatic detection of sugar beet, which may be used to determine accurate fungicide application.

Item Type

ethesis

Thesis Type

PhD

Supervisors

Stetkiewicz, Stacia

University of Nottingham

Foulkes, John