Evaluation of short day onion (Allium cepa L.) genotypes for quantity and quality traits

Purpose: In the first stage to produce open pollinated and hybrid onion cultivars, identification of compatible genotypes as breeding base populations with the climatic conditions is of special importance. Thus, this research was performed to evaluate short day onion hybrids and achieve a breeding base population by identifying the best genotypes in terms of quantity and quality traits and also for studying the reaction of genotypes to the climatic conditions of Isfahan and Khuzestan. Research method: Fifteen onion genotypes were evaluated as complete block design with three replications in two locations (Isfahan and Khuzestan) under field condition during the 2017-2018 growing season. The traits evaluated included: bulb yield, average bulb weight, dry matter content, total soluble solids, and weight loss. Findings: According to the results of Isfahan location, Savannah Sweet and Saba hybrids had the highest bulb yield (42.72 t/ha and 41.05 t/ha, respectively) and Vania hybrid with high significant different (p< 0.05) was showed the lowest bulb yield (19.77 t/ha). In Khuzestan location, SV6326, Saba and Savannah Sweet for bulb yield (92.38, 89.71 and 89.14 t/ha, respectively) were recognized as super hybrids, in contrast, hybrids: Early Super Select, Behbahan improved population, Super Perfect, Sahar and Vania, were considered as weak hybrids (bulb yields