Aphid-resistant lettuce varieties offer a solution for growers

Happinas RZ and Friendlinas RZ, the two new iceberg lettuce varieties with high resistance against Nasonovia ribisnigri (Nr:0,1), are a major advancement for lettuce growers worldwide. The varieties not only offer a solution to the troublesome currant-lettuce aphid, but also meet all other quality requirements. “Growers can see the iceberg lettuces for themselves during our Demo Days in September,” says Peter Sonneveld, Crop Coordinator Lettuce at Rijk Zwaan.  

Peter, who is responsible for lettuce in northern and central Europe, is the lynchpin between growers and the company’s breeders, whom he refers to as ‘wizards’. “They can create varieties that are tailored to market demands – such as the two iceberg lettuce varieties we’re now presenting with high resistance against Nr:0,1.”  

Ban on systemic pesticides 

The crop coordinator expects growers to be very interested in these varieties, because Nasonovia ribisnigri is causing them considerable problems. “This aphid is a real headache, particularly for lettuce growers in the European Union. They are asking themselves how they can keep their crops aphid-free, especially now they will no longer be allowed to use systemic pesticides containing Spirotetramat as the active ingredient as of next season,” he explains.  

Various growers and research institutes have been testing alternatives for aphid control, according to Peter, including biological insecticides and chemical agents that will still be allowed next year. So far, the results have been unsatisfactory, he says: “Growers still see too many aphids in lettuces.” 

Difficult to wash off 

If a lettuce head is infested with aphids, it is basically unsaleable. “Retailers and consumers don’t accept bugs in their lettuces. Even companies that process and package lettuce are struggling with this issue. They have conducted tests to see whether the aphids can be washed off, but it’s more difficult than expected,” explains Peter. 

Hardly any aphids 

In other words, the new Nr:0,1-resistant iceberg lettuce varieties are a welcome solution for the whole value chain. Peter saw with his own eyes just how effective this resistance is when he visited a field trial in September 2024. “My colleagues had released lettuce aphids in a field containing existing varieties and the new ones. Hardly any aphids could be found in the new varieties. That made me really happy.” 

Practical trials 

As a result, the next phase – practical trials – received the green light in late 2024. Peter immediately sat down with Rijk Zwaan’s crop specialists and trial coordinators to plan trials at 20 growers’ facilities in north-western Europe in 2025.  

“The main aim was to assess the agronomic traits, such as head shape, base, weight and susceptibility to tipburn. Both varieties performed amazingly well. We’re very satisfied. Needless to say, we’re happy to share the details with growers.”

Nasonovia Defense label 

The new varieties were named Happinas and Friendlinas for a reason. “They offer the market a real solution, so they put a smile on my face – and I expect on growers’ faces too,” comments Peter.  

Growers who are interested in the new iceberg lettuce varieties can contact their Rijk Zwaan representative. “We have planned the seed production carefully, so we believe we can meet the demand,” says the crop coordinator. He adds that Nr:0,1-resistant varieties of other lettuce types will follow shortly, all under the Nasonovia Defense label.  

Demo Days in September  

People who would like to see the Nasonovia Defense varieties for themselves are welcome to visit the Rijk Zwaan Demo Days this autumn. The Open Field Demo will be held in the Dutch town of Fijnaart from 15 September to 10 October.  

“I will be present at that event,” Peter states. “We’re looking forward to meeting our customers there. The introduction of these varieties was the result of many years of teamwork among colleagues from all areas of the company. It feels good to finally be able to share this innovation with growers.”