News - 29-06-2026
Lt Defense™: improved resistance in global pepper segments
Good news for growers of sweet and hot peppers: varieties with the latest version of Lt Defense resistance offer better protection against powdery mildew. “From now on, we’re stacking multiple resistance genes in our varieties, making the crops stronger against Leveillula taurica (Lt). That gives growers peace of mind,” says Paul Maris, Breeding Manager Peppers at Rijk Zwaan.
Powdery mildew is a challenge for pepper growers on every continent, according to Paul. “Whether in low-tech sweet peppers in Mexico, plastic greenhouses full of sweet pointed peppers in Spain or Dutch high-tech greenhouses growing blocky peppers, this fungal disease occurs everywhere,” he explains. “Growers mainly tackle it using sulphur and/or crop protection agents. Resistances help them manage powdery mildew more sustainably. That’s why Lt Defense is such an important part of our breeding programme.”
New version of Lt Defense
Lt Defense now offers even better protection. “When fungal pressure is high and climate conditions are favourable for the fungus, older resistant varieties can, to a certain extent, still be harmed by the disease because the fungus keeps adapting,” explains the breeding manager. “That’s why we now offer stronger pepper varieties with the new and improved version of Lt Defense. This resistance involves several genes rather than just one. Thanks to marker techniques, we can identify the relevant genes more quickly and combine them in new varieties.”
Strict criteria
The updated Lt Defense range meets a number of strict criteria. Paul explains how it works: “Our scores range from 0 to 6. A score of 6 indicates susceptible varieties, while a score of 0 indicates highly resistant ones. Only pepper varieties with a score of 3 or lower qualify for our Lt Defense label.”
Tested in practice
Real-world testing plays an essential part in determining those scores. “We test the resistance of mature plants under commercial conditions, across multiple years and at various locations. That’s how we offer growers certainty that the protection works in practice,” states Paul.
Across all pepper segments
The new Lt Defense resistance has already been incorporated into a number of Rijk Zwaan’s sweet and hot varieties. The breeding team is now working on offering the same protection against mildew across most pepper segments, for low-tech, mid-tech and high-tech systems. Paul: “Our team is very committed to this task. Lt Defense is an excellent example of how we’re contributing to more sustainable crop production and greater peace of mind for growers worldwide.”
Choose Lt Defense
Are you curious which pepper and hot pepper varieties with Lt Defense are available in your local market? Contact your Rijk Zwaan representative for tailor-made advice.