BYDV PREDICTOR: a simulation model to predict aphid arrival, epidemics of Barley yellow dwarf virus and yield losses in wheat crops in a Mediterranean‐type environment

Abstract

BYDV PREDICTOR, a simulation model, was developed to forecast aphid outbreaks and Barley yellow dwarf virus (BYDV) epidemics in wheat crops in the grainbelt region of southwest Australia, which has a Mediterranean-type climate. The model used daily rainfall and mean temperature to predict aphid ( Rhopalosiphum padi ) buildup in each locality before the commencement of the cereal-growing season in late autumn, and to forecast the timing of aphid immigration into crops. The introduction of BYDV by aphid immigrants, aphid buildup within the crop, spread of BYDV, and yield losses were predicted for different sowing dates. The model simulations were validated with 10 years' field data from five different sites in the grainbelt, representing a wide range of scenarios. When first aphid arrival dates ranging from 1 June to 2 September were compared with predictions, 65% of the variation between sites and years was explained. Progress curves for the predicted percentage of plants infected with the serotype BYDV-PAV closely resembled the starting point and shape of those recorded in 14 out of 18 scenarios. Sensitivity analysis confirmed that the combination of a high proportion of immigrants vectoring BYDV, early sowing of crops and early start to aphid arrival relative to sowing date led to the most BYDV spread and greatest yield loss. The model was incorporated into a decision support system used by farmers in targeting sprays against aphids to prevent virus spread in autumn and winter. BYDV PREDICTOR could serve as a template for modelling similar virus/aphid vector pathosystems in other regions of the world, especially those with Mediterranean-type climates.

Virus disease in wheat predicted to increase with a changing climate

“…BYDV infection in the early growth stages of cereal crops, including wheat, can dramatically increase yield loss (Gildow & Frank, ; Thackray et al ., ; Finlay & Luck, ). Additionally, greater B/CYDV titre and higher temperature can increase aphid ability to acquire and transmit the virus (Gray et al ., ; Power & Gray, ; Lucio‐Zavaleta et al ., ; Jiménez‐Martínez & Bosque‐Pérez, ).…”

Climate drivers, host identity and fungal endophyte infection determine virus prevalence in a grassland ecosystem

“…Abiotic variables can also have a strong impact on viral disease dynamics in grasslands Power et al 2011), especially precipitation and temperature which often explains variation in the extent of virus epidemics for agricultural systems (Jones et al 2010) as well as in pastures and wild grasslands (Thackray, Diggle & Jones 2009). Previous work in our pathogen system indicates that precipitation can be a major driver.…”

Population Dynamics and Diapause Response of the Springtail Pest Sminthurus viridis (Collembola: Sminthuridae) in Southeastern Australia

“…could probably be predicted by a combination of soil moisture and low temperature. A simulation model has recently been developed for predicting outbreaks of aphids and barley yellow dwarf virus in Australia that uses rainfall and temperature data (Thackray et al 2009). A similar approach could be taken for predicting the emergence of S. viridis, although a larger data set involving multiple sites and sampling years would be required to develop and validate a model accurately.…”