Spring bean crops are growing incredibly quickly in current ideal conditions, to naturally compensate for later sowing. Emergence has also been excellent in most crops, with high plant numbers where growers were able to increase seed rates accordingly, reports Syngenta Field Technical Manager, Simon Jackson.

However, with the wet weather there has also been a high incidence of chocolate spot, including further spread onto new growth through rain splash in heavy downpours. “When plants are rapidly growing it’s imperative to use a product that effectively moves throughout the leaf, to protect against infection,” he advised.

Simon advocates growers and agronomists prioritise Elatus Era for the key T1 fungicide applications in early June, to take advantage of the strong efficacy against both rust and chocolate spot. “While the crop is growing and extending leaf area, Elatus Era will give protection against chocolate spot, as well as excellent results on rust if conditions turn hotter and drier.

“That would enable growers to follow up with an Amistar treatment when the crop is approaching full canopy growth stage.”

Where crops are identified with high levels of early disease infection, typically before the end of May, an initial T0 application may also be justified, he added. 

With the late sowing of most spring bean crops, ensuring plants remain clean and healthy for as long as possible will be crucial to fully benefit from the good establishment this season. PGRO research has shown that achieving 65 plants per m² for spring beans from a late sowing retains the potential to yield up to 7.0 t/ha, compared to less than 6.0 t/ha if the established plant population is around 40 plants per m². However, the work also suggested that on fertile soils, or areas that produce very vigorous growth, target plant populations of 45-55 plants per m² can still achieve optimum yields. 

In Syngenta trials, the use of Elatus Era in the bean fungicide programme extended green area retention to 96.6%, when the corresponding untreated plots had declined to less than 38%. Other fungicide options in the trial maintained 71% and 90% green leaf at the same point. Final crop yield performance mirrored the green leaf area results, producing 5.82 t/ha with Elatus Era, compared to 5.09 t/ha from an untreated crop.

“Using Elatus Era at T1 will provide protection low down in the canopy and prevent disease re-establishing on leaves - which frequently leads to an explosion of infection when the crop reaches full canopy,” Simon highlighted.

“There is still excellent potential in many spring beans crops, with ample soil moisture and temperatures warming to seasonal norms. Investing in a good disease control programme and helping the plant maintain green leaf area for as long as possible will help to build yield.”