Many factors combine to influence the risk of losses to TSWV. Some factors are more important than others, but no single factor can be used as a reliable TSWV control measure. Research data and on-farm observations indicate that when combinations of factors are considered, an individual field’s risk of losses due to TSWV can be estimated.
There is no way to predict with total accuracy how much TSWV will occur in a given situation or how the disease will affect yield, but by identifying high-risk situations, growers can avoid those production practices that are conducive to major yield losses.
The University of Georgia Tomato Spotted Wilt Risk Index for Peanuts was developed as a tool for evaluation of risk associated with individual peanut production situations.
When high-risk situations are identified, growers should consider making modifications to their production plan (i.e. variety, planting date, seeding rate, etc.) to reduce their level of risk. Using preventative measures to reduce risk of TSWV losses is the only way to control the disease.
Risk levels are relative. If this index predicts a low level of risk, we would expect that field to be less likely to suffer major losses due to TSWV than a field that is rated with a higher level of risk. A low index value does not imply that a field is immune from TSWV losses. Losses due to TSWV vary from year to year.
Measuring Risk To Fungal Diseases
The index presented here is designed to help growers approximate the magnitude of the risk that they face from foliar and soilborne diseases in the coming season. More importantly, it should serve as an educational tool that allows the grower to predict the benefits of different management practices he makes in hopes of producing a better crop.
The risks associated with leaf spot, white mold and Rhizoctonia limb rot diseases are to be determined independently in the index system.
When weather conditions are favorable for fungal diseases, especially when rainfall is abundant, even fields at initial “low risk” to fungal diseases may become “high risk.”
For each of the following factors that can influence the incidence of TSWV or fungal disease, identify which option best describes the situation for an individual field. An option must be selected for each risk factor, unless the information is “unknown.” A score of “0” for any variable does not imply “no risk,” but that this practice does not increase the risk of disease as compared to the alternative. Add the index numbers associated with each choice to obtain an overall risk index value. Compare that number to the risk scale provided and identify the projected level of risk.
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