VARIETAL RESPONSE to ear was fungicides depends on a range of factors beyond product choice, says one expert.

Ripening speeds and disease resistance will also influence how much specific varieties respond to ear sprays, said plant breeder, John Blackman.

For example, varieties that “finish” quickly are likely to give a bigger response to the greening effect of strobilurins than those that naturally stay green for longer, such as Hereward and Robigus, he said.

“Varieties such as Malacca, Xi19, Claire and Tanker are naturally fast at shedding green leaf, so there is a real benefit in keeping them alive.”

Growers should avoid applying too high a dose of harsh EC (Emulsifiable Concentrate)-formulated eradicant fungicides, as they can have a negative impact on waxy varieties like Robigus and Hereward, he added.

“They seem to have a different kind of wax, which can be removed by eradicant fungicides. On these varieties growers need to ask whether they can use a kinder treatment.

“EC treatments should only be used in high disease risk situations.”

For a tactical update on ear wash advice, together with the latest offerings from the leading firms, see FARMERS WEEKLY June 3, or Crops June 4 for a head-to-head T3 product comparison.