Ground-Breaking Zucchini with Downy Mildew Resistance
Squash producers, harvesters and even home gardeners know the tell-tale patchy signs of downy mildew. It’s the first sign that the plant is about to perish, despite any and all interventions. Among a sea of squash-affecting viruses and diseases, it can be the deadliest.
But one of Syngenta’s newest squash offerings, Fortress, could change the game. It is the first ever squash with downy mildew resistance. With ground-breaking resistance, the plants can withstand the disease’s attacks. In fact, it even generates new growth after exposure to downy mildew.
“Fortress plants maintain quality and yield potential — and produce new growth — while other varieties can completely melt down to the ground,” said Les Padley, Squash Breeding Project Lead at Syngenta Vegetable Seeds.
In addition to downy mildew resistance, Fortress also includes an elevated Syngenta disease package with intermediate resistance to cucumber mosaic virus, watermelon mosaic virus, zucchini yellow mosaic virus, powdery mildew, and papaya ringspot virus.
“With these levels of resistance, growers can be assured that plants will maintain quality of the crops throughout the growing season, harvesting consistently in the field with high-quality fruits,” Padley said.
Fortress has an upright, strong structure that lends itself to easy harvesting and its plants have high yield potential. Fortress is adapted specifically for the zucchini market in the U.S., centered on the eastern seaboard from Florida to New York.
Guillaume Menet, who leads the global squash breeding program at Syngenta, said “We have access to the right genetics and a strong pipeline of varieties. Disease resistance is – and always has been – a top priority for Syngenta.”
With the consistent emergence of new diseases or new disease varieties, Syngenta has a team in place to ensure swift action, and even pro-active planning. Commercial and trialing teams work with growers to identify new threats quickly and communicate these up the chain to Syngenta’s team of breeders.
“Here at Syngenta, we work closely with growers and dealers,” Padley said. “When a key trait is identified, we work to find it in our germplasm and add it to our commercial varieties to get the growers the highest quality product we can. Our goal is the highest disease package, best fruit and plant characteristics.”
Padley’s most famous work may be Fortress, but he’s also responsible for many of the yellow squash varieties on sale in North America and was named by Growing Produce as one of the “8 rockstar vegetable breeders” in 2024.
“I just get excited seeing the varieties we create on the shelves,” he said. “Knowing people can consume it, knowing we’re providing local stores and the food supply.”
All photos are either the property of Syngenta or are used with permission.
© 2026 Syngenta. Some or all of the varieties may be protected under one or more of the following: Plant Variety Protection, United States Plant Patents and/or Utility Patents and may not be propagated or reproduced without authorization.
The trademarks or service marks displayed or otherwise used herein are the property of a Syngenta Group Company.
