Evaluation of Azarshar red onion morphotypes for agronomic attributes

In order to evaluate agronomic attributes of six Azarshar red onion morphotypes, an experiment was conducted in Shabestar region, Iran in a randomized complete block design (RCBD) with three replications. Seeds of experimental onion landreces were collected under isolated condition and onion yield, bulb diameter, number of centers, dry matter percentage, number of edible layers, number of bulb scale, and percentage of twin onions were measured. Cluster analysis grouped the morphotypes into three clusters. However, grouping based on agronomic attributes showed no correspondence with the geographical pattern. Ssignificant differences in all studied attributes, except number of bulb scale, indicated diversity among Azarshar red onion morphotypes. According to the results, Azarshar red onion landrace is a potential resource of useful genes for breeding programs. The results revealed that the red onion morphotypes was not suitable for industrial processing due to the their low dry matter percentage and should be used in fresh-market. Furthermore, the correlation between measured attributes showed that selection of onions with larger diameter could be suitable in breeding for higher yield.