Planning for effective fireblight control

Planning is underway for the coming season’s fireblight control options in pipfruit. Understanding the optimal application timing for each product helps achieve the best disease control and supports resistance management tactics to protect the ongoing effectiveness of streptomycin.

Serenade® Optimum is one option available for fireblight control. It is an optimised fermentation product of a unique microbial strain: the QST 713 strain of Bacillus subtilis. While there are other strains of B. subtilis, QST 713 differs from others in the types and amounts of biological chemistry that it produces.

All Serenade products are manufactured using a highly optimised, well-controlled fermentation process that results in a consistent product. Each batch of Serenade contains a standardised viable spore count of the QST 713 strain of B. subtilis, as well as standardised levels of biological chemistry. Serenade is shelf-stable, not requiring refrigeration like some Bacillus products.

Phil Bertram, Bayer’s Upper North Island Business Manager, says, “Serenade has dual antibacterial biological chemistries, which inhibit cell division, protein and cell wall synthesis of Erwinia amylovora, the pathogen which causes fireblight. Also, Serenade is an antagonistic coloniser of the emerging leaves and flowers, excluding bacteria from colonising the same site. Once applied, the QST 713 can grow and colonise in situ, with peak colonisation occurring 24 hours after application.”

Serenade Optimum is best used preventatively and applied during periods of lower fireblight pressure and early or later bloom with lower numbers of flowers. From early flowering, apply Serenade at three-to-seven day intervals to maintain colonisation of flowers. 

For late flowering, under extreme fireblight pressure, apply streptomycin as per label directions. Post-flowering, Serenade Optimum also protects newly grown shoots. There is no need to apply Serenade separately. It can be tank-mixed with most commonly-used fungicides and insecticides, including copper.

ACVM registration number: Serenade Optimum #P009409. Read registered label before use.