Syngenta Vegetable Seeds is expanding its North American onion portfolio with the introduction of Roundo, an early-season yellow onion, and Olympo, a main-season white onion, as growers seek varieties that can balance field performance with the quality standards demanded by fresh-market and processing channels.
The two long-day varieties have been developed to support consistent bulb quality, high percentages of single centers and dependable bolting tolerance across diverse growing environments. The launch reflects Syngenta’s broader strategy of combining agronomic resilience with the characteristics that influence marketable yield, packout quality and consumer appeal.
Roundo is positioned as an early-season yellow onion with broad adaptability, particularly across growing regions in the western United States. With an average maturity of 105 days, the variety produces globe-shaped bulbs in a colossal size class, supported by strong skin quality and a high percentage of single centers. Its low bolting tendency under challenging growing conditions is intended to provide greater production reliability, while its suitability for both fresh-market and processing applications gives growers additional marketing flexibility.
Olympo, meanwhile, targets the main-season white onion segment. Maturing in approximately 125 days, it produces globe-shaped, jumbo-sized bulbs with exceptional skin quality and thin necks. The variety combines a high percentage of single centers with reliable bolting tolerance, traits designed to support consistent crop performance and improve marketable output from the field through harvest and packout.
For Syngenta, the development of new onion varieties begins with grower requirements. David Whitwood, Onion Breeder at Syngenta Vegetable Seeds, said grower feedback plays a central role in determining which traits are prioritised and how available germplasm is used to develop new products.
“Grower feedback is absolutely essential,” Whitwood said. “The best opportunity for grower success is listening to the grower, pulling in their current requests and needs, and then putting that together with the germplasm we currently have to develop the best product.”
The breeding programme also addresses disease pressures that can affect onion yield and quality across regions, including downy mildew, Fusarium and powdery mildew. Alongside disease resistance, breeders are focusing on shape uniformity, single centers and storability.
Miguel Guillén, Product Specialist for the western United States at Syngenta Vegetable Seeds, said the breeding process requires a balance between field performance and the characteristics valued by buyers and consumers. “It’s a careful balance between agronomic traits and consumer traits,” he said.
The company’s approach draws on germplasm from around the world while testing varieties across multiple production environments. This global-to-local model is designed to help breeders identify combinations of traits suited to specific markets and growing conditions.
Syngenta is continuing to build its onion portfolio across short-day, intermediate-day and long-day segments, as well as across different bulb colours. With Roundo and Olympo, the company is adding two varieties aimed at addressing different points in the production calendar while maintaining a common focus on dependable performance and marketable quality.
As weather variability, disease pressure and market specifications continue to influence variety selection, the success of new onion genetics will increasingly depend on their ability to perform consistently beyond trial plots. For Syngenta, Roundo and Olympo represent the latest additions to a broader effort to combine global breeding resources with the practical needs of growers and the markets they serve.
