The International Bremia Evaluation Board Europe (IBEB-EU) has confirmed that no new races of Bremia lactucae—the pathogen responsible for downy mildew in lettuce—have emerged in 2025. The organization noted that four previously identified races—Bl:38EU, Bl:39EU, Bl:40EU, and Bl:41EU—continue to dominate in European fields, with Bl:41EU alone now representing 41% of all collected samples.

Trends indicate a growing prevalence of Bl:38EU and Bl:39EU, while Bl:40EU appears to be on the decline.

In response to the ongoing pressure posed by these aggressive races, vegetable seed company Enza Zaden emphasized the critical importance of deploying resistant lettuce varieties. In a recent press statement, the company stressed that its leafy crop portfolio offers complete resistance from Bl:29EU through Bl:41EU, without compromising on agronomic performance.

“Now more than ever, resistant portfolios are critical in the fight against Bremia,” the company said. “Our varieties help growers safeguard their crops and maintain high yields despite rising disease pressure.”

Enza Zaden’s lettuce offerings span a range of leafy segments and are designed not only to perform well in the field but also to deliver quality across the entire supply chain. According to the company, this includes longer shelf life for retailers and cleaner, healthier produce for consumers.

Bremia lactucae remains one of the most destructive diseases affecting lettuce production, capable of triggering severe economic losses. Enza Zaden said its focus on breeding varieties with high resistance helps reduce the need for chemical fungicides, lower production costs, and promote more stable yields under variable conditions.

“Our resistant portfolios are designed to offer growers a comprehensive defense against downy mildew,” the statement concluded, “supporting best practices in disease prevention and advancing sustainable agriculture.