• Clean bean leaves growing well in treated crops
• Attention turns to rust prevention with Elatus Era
• Vixeran biofertiliser proven effective to boost pod retention and bean weight
• Spring agronomy aims to deliver consistency with higher yields

After unprecedented severe attacks of chocolate spot in beans earlier this season, that has seen some fields decimated, most crops that received an early fungicide treatment have started to recover, with clean growth emerging in warmer drier conditions.

Significant levels of inoculum are still present on lower diseased leaves, however, with ongoing fungicide protection still required on emerging leaves, and especially as crops reach the all-important first pod stage, advocates Syngenta Technical Manager, Simon Jackson.

“Treatment timings are a balance between managing costs and necessary disease control,” he highlights. “Current crop growth would indicate the first pod stage will be earlier than normal. Timing for Elatus Era application, from first flower buds visible (BBCH51), could potentially happen as early as late April this season.”

The key bean fungicide timings, as shown by research at PGRO, are first pod set, with a final application 21 to 28 days later.   

“Syngenta trials have shown that controlling rust early with Elatus Era reduces rust incidence later.  Given the high level of inherent disease risk this year, a robust rate of 0.66 l/ha will also give good control of chocolate spot, as shown in trials,” Simon advises. “Elatus Era has proven a good option to build a strong base for rust control.” 

 Mid-April is also a good time to think about nutrition in beans, he suggests.  The YEN project has highlighted the importance of applying nutrients in bean crops. 

“Trials for the last three years have shown that Vixeran, a unique bacteria solution which fixes atmospheric nitrogen, helps to improve yields.  Bean plants are naturally set up to work with symbiotic rhizobium bacteria they host in root nodules; Vixeran lives in the leaves and around the root to fix further atmospheric nitrogen into ammonium, which is readily available to the plant,” explains Simon. 

“This can be especially beneficial where soils are inherently low in rhizobial bacteria, or where the nodules have been damaged by pea and bean weevil larvae.”  Syngenta recommend a Vixeran application from the 6 true leaf stage (BBCH16), through to early flower.

“Application conditions are more crucial than timing,” says Simon. “The crops should be actively growing. Avoid application just before or after frost events, and aim to avoid treatment if periods of bright sunshine are forecast immediately after application.” 

Recent trials work with PGRO has shown that Vixeran treated crops retained more pods per plant and improved bean weight - the crucial components that lead to increased yields. 

Simon points out that bean crops also respond especially well to sulphur supplements, which should be considered at the April timing along with magnesium. Trace elements such as manganese, boron and zinc should also be assessed, with leaf tissue analysis giving an indication of crop nutrient status. 

As the season progresses, Simon outlines an application of Amistar fungicide 21 to 28 days after the Elatus Era treatment will provide good control of rust later in the crop. “It will also give broad spectrum protectant disease control with a good contribution to downy mildew which may appear late,” he advises. “We would recommend mixing Amistar with a triazole if rust pressure is high, or there is still chocolate spot is still present.

“The aim to help make bean yields more consistent, resulting in a more sustainable return from this important crop,” he adds.