Article taken from The Fruit Grower
The new early warning system, a first in the UK market, was released in May. It is available free of charge to GCI subscribers, says Agrovista fruit agronomist Alex Radu.
“Fireblight is a potentially serious disease on apples and pears caused by the bacterium Erwinia amylovora. There is no chemical cure available, so growers have to rely on copper-based preventative or antagonistic sprays before the disease takes hold,” he explains. “This makes accurate forecasting all the more vital.”
Fireblight infection occurs through blossom and new growth when the weather is favourable and inoculum is present. The new fireblight software, developed by Dutch pest and disease software forecasting specialist RIMpro, calculates the likelihood of infection, based on flowering period obtained from weather information and observation, and likely contamination and bacterial growth, based on temperature and relative humidity/rainfall.
The quality of the forecast is completely dependent on the accuracy of these weather predictions, says Alex Radu. This information is supplied from live weather data collected GCI from a network of over 35 weather stations across the country, from which highly accurate local forecasts can be modelled.
“Erwinia becomes a threat at 18C or more, when conditions are wet,” Alex explains. “Growers whose orchards have a history of disease can assume it is there, and we can now help them forecast potential outbreaks with greater accuracy. This means we can improve the timing and efficacy of preventative applications, which will be a real benefit to growers in managing disease. It will also reduce the number of applications required and ensure that they are targeted more effectively, saving growers money and helping to reduce the presence of residues in the environment and the crop.”
The new software cements Agrovista’s lead in online technologies, and confirms GCI as the most up-to-date-online disease and pest forecasting service for top fruit growers.
The GCI package now includes RIMpro’s primary and secondary scab, codling moth, canker, and fireblight forecasts, as well as the weather data recorded at that station. All stations display a 10-day forecast for all the models. Subscribers can access live graphics, and text alerts are available for major events. Daily emails are also available for the local weather forecast, likely spraying conditions and spray application windows.
The bar at the bottom shows leaf wetness readings in light blue and active rain as dark blue, as registered by the on-farm weather station. The lower graph shows the growth of the Erwinia population on the stigma after contamination. Each black line stands for a new group of flowers. The middle graph shows the potential infection incidence as calculated from flower age and level of the infecting bacterial population. The upper graph shows the growth within the plant o the Erwinia population after infection.
In this case, taken from an orchard in central Europe when the model was being developed, the weather during flowering was very favourable for the development of high Erwinia population levels on the stigmas. Six wetness events caused potential infection events.
Since the earliest infections rarely result in symptoms, sprays can be adjusted depending on individual risk management preferences. Nonetheless, at least two sprays were needed to adequately manage fireblight – the first spray in relation to the 20 April infections, and a second spray for flower groups that opened later and which led to infection between 25 and 28 April.
What the grower sees
The new early warning system, a first in the UK market, was released in May. It is available free of charge to GCI subscribers, says Agrovista fruit agronomist Alex Radu.
“Fireblight is a potentially serious disease on apples and pears caused by the bacterium Erwinia amylovora. There is no chemical cure available, so growers have to rely on copper-based preventative or antagonistic sprays before the disease takes hold,” he explains. “This makes accurate forecasting all the more vital.”
Fireblight infection occurs through blossom and new growth when the weather is favourable and inoculum is present. The new fireblight software, developed by Dutch pest and disease software forecasting specialist RIMpro, calculates the likelihood of infection, based on flowering period obtained from weather information and observation, and likely contamination and bacterial growth, based on temperature and relative humidity/rainfall.
The quality of the forecast is completely dependent on the accuracy of these weather predictions, says Alex Radu. This information is supplied from live weather data collected GCI from a network of over 35 weather stations across the country, from which highly accurate local forecasts can be modelled.
“Erwinia becomes a threat at 18C or more, when conditions are wet,” Alex explains. “Growers whose orchards have a history of disease can assume it is there, and we can now help them forecast potential outbreaks with greater accuracy. This means we can improve the timing and efficacy of preventative applications, which will be a real benefit to growers in managing disease. It will also reduce the number of applications required and ensure that they are targeted more effectively, saving growers money and helping to reduce the presence of residues in the environment and the crop.”
The new software cements Agrovista’s lead in online technologies, and confirms GCI as the most up-to-date-online disease and pest forecasting service for top fruit growers.
The GCI package now includes RIMpro’s primary and secondary scab, codling moth, canker, and fireblight forecasts, as well as the weather data recorded at that station. All stations display a 10-day forecast for all the models. Subscribers can access live graphics, and text alerts are available for major events. Daily emails are also available for the local weather forecast, likely spraying conditions and spray application windows.
The bar at the bottom shows leaf wetness readings in light blue and active rain as dark blue, as registered by the on-farm weather station. The lower graph shows the growth of the Erwinia population on the stigma after contamination. Each black line stands for a new group of flowers. The middle graph shows the potential infection incidence as calculated from flower age and level of the infecting bacterial population. The upper graph shows the growth within the plant o the Erwinia population after infection.
In this case, taken from an orchard in central Europe when the model was being developed, the weather during flowering was very favourable for the development of high Erwinia population levels on the stigmas. Six wetness events caused potential infection events.
Since the earliest infections rarely result in symptoms, sprays can be adjusted depending on individual risk management preferences. Nonetheless, at least two sprays were needed to adequately manage fireblight – the first spray in relation to the 20 April infections, and a second spray for flower groups that opened later and which led to infection between 25 and 28 April.
What the grower sees