White mold
White mold is a fungal disease caused by Sclerotinia sclerotiorum and is consistently ranked as a high priority for improved management in snap, dry and lima bean in New York. Epidemics in processing snap and lima bean fields in New York often result in losses ranging from 40 to 60%. Cornell University has a strong history of conducting research on white mold reflecting the importance of this disease in New York.
Below are some examples of recent research outcomes from our work on this disease:
Pathogen Biology and Ecology:
Research is continuing to advance knowledge in S. sclerotiorum population biology including:
- Genotypic diversity across New York.
- Genotypic diversity and differentiation in populations in temperate and tropical environments.
Defining Risk:
Probability distributions have been designed for quantifying the spatial attributes of white mold epidemics in processing snap bean fields in New York. These distributions form the basis of hierarchical sampling procedures which could be used by crop scouts to assess the incidence of white mold prior to harvesting. If the incidence of white mold is over a specific threshold often the crop is not harvested resulting in complete crop loss to the grower.
- Probability distributions for marketable pods and white mold in snap bean.
- Hierarchical models for white mold in snap bean.
- A meta-analytical approach was also used to quantify the effect of white mold on soybean production in collaboration with colleagues from Brazil.
Disease Management:
The in vitro sensitivity of a S. sclerotiorum population from New York to three commonly used fungicides (fluazinam, thiophanate-methyl, and boscalid) has been evaluated and found only limited evidence of reduced sensitivity to thiophanate-methyl.
Our research into white mold has suggested that the primary contributing factor to suboptimal disease control is poor timing of fungicides. For optimal results, fungicides must be applied at early flowering as ascospores are only able to infect floral tissues.
Ongoing research on white mold in the EVADE program is investigating:
- Novel methods to inhibit carpogenic germination of S. sclerotiorum;
- Efficacy and optimal timing of fungicides for white mold management;
- Use of hyperspectral imagery with UAS to improve fungicide timing for optimal disease control in collaboration with Cornell Cooperative Extension Regional Vegetable Program and imaging scientists at the Chester F. Carlson Center for Imaging Science, Rochester Institute of Technology; and
- Development of multivariate risk models for predicting white mold epidemics in snap bean.