Table beet diseases
In New York, table beet is grown in diverse production systems ranging from broadacre cropping systems to small, diversified farms using either conventional or organic methods. Substantial production factors affecting beet productivity in New York are disease and weed management. Our research program working on the full spectrum of diseases affecting table beet from those affecting crop stand establishment, the maintenance of healthy foliage, and root yield and quality.
Recent activities have focused on the foliar disease, Cercospora leaf spot caused by the fungus, Cercospora beticola as this is the primary cause of defoliation
. Cercospora leaf spot epidemics can lead to significant reductions in yield and in some cases, total crop loss. In processing table beet crops, foliar disease may make mechanized harvesting impossible. The dominant method of control in broadacre crops is multiple fungicide applications. However, strobilurin fungicide resistance was reported in 2012, highlighting the imperative to identify fungicides for use in conventional production and build resilience into disease management recommendations. Our research is also strongly supporting the organic table beet industry in New York.
Some examples of our research findings from our table beet disease program within our thematic program areas are outlined below:
Pathogen Biology and Ecology:
Despite the importance of Cercospora leaf spot, large gaps persist in the biology of this pathogen. Little is known about the spread of the pathogen between and within fields limiting the design of effective management strategies For example, despite heterothallism a teleomorph has not been described. Moreover, the role of alternative hosts responsible for providing green bridges for inoculum are not well understood.
Our recent findings on the population biology and aetiology of Cercospora beticola are outlined in these publications:
- De novo genome assembly and the development and validation of microsatellite markers.
- Genetic structure of Cercospora beticola populations in New York and Hawaii.
- Global gene flow within Cercospora beticola confirmed through genotype-by-sequencing.
- Temporal changes in genetic diversity and differentiation of Cercospora beticola populations.
- Population biology of Phoma betae in foliar and root disease of table beet.
- Genetic structure and diversity of Cercospora beticola from Beta vulgaris ssp. vulgaris.
- Species-specific detection of Cercospora beticola by quantitative PCR.
Research has also continued to expand our knowledge of the diseases affecting table beet in New York.
- Incidence and pathogenicity of Didymella americana on table beet in New York.
- Southern Sclerotium root rot on table beet in New York.
Disease Management:
- Genotypic diversity and resistance to azoxystrobin of Cercospora beticola on processing table beet in New York.
- Management of Cercospora leaf spot in conventional and organic table beet production.
- Horticultural characteristics and cultivar susceptibility of table beet cultivars to Cercospora leaf spot in New York.
- Table beet cultivar susceptibility to Phoma leaf spot.
- Alternative hosts for Cercospora beticola.
- Disease management challenges for the New York table beet industry.
Ongoing research into the diseases affecting table beet within the EVADE program includes:
- Utility of forecasting systems and action thresholds for Cercospora leaf spot control in table beet;
- Sequential sampling plants based on spatial attributes of Cercospora leaf spot in table beet.