A NETWORK APPROACH TO ONION VARIETAL EVALUATION IN THE TROPICS
Since 1990, NRI and the Horticulture Research International (HRI) have been sending seed of commercially available short-day onion varieties to collaborators for use in national trials in tropical, subtropical, and a few Mediterranean climates.
Overall, cultivars of the Early Grano and hybrid Granex groups usually produce the highest yields, while cultivars of the Creole type and of Indian stocks are lower yielding in most of the tropical environments from which results have been received. Some cultivars sold under the same name are showing evidence of genetic divergence. Genetic progress towards storage quality improvement in high-yielding yellow-brown onions from Israel has been confirmed. Requirements for high-yielding, red, pungent onions with good storage quality are not yet fully met in the tropics.