%0 Journal Article %T Field Evaluation of Twelve Clones of Oregano Grown in the Main Production Areas of Argentina: Identification of Quantitative Trait with the Highest Discriminant Value %A Lorena E. Torres %A Paula C. Brunetti %A Carla Baglio %A Pablo G. Bauz¨˘ %A Ana G. Chaves %A Yamile Massuh %A Sonia F. OcaŁżo %A Marta S. Ojeda %J ISRN Agronomy %D 2012 %R 10.5402/2012/349565 %X In Argentina, oregano (Origanum spp.) is one of the most important aromatic species. Leaves and flowering tops are used as seasoning, targeting the retail consumer, industrial and less to export. Local production has low-average yields due to the variability of cultivated material, the vegetative propagation methods used, and the lack of knowledge and adaptive experimentation on advanced cultivation practices. Clones of oregano grown in the country were collected in order to characterize the germplasm used in Argentina. Twelve oregano clones, sanitized by meristems culture and micropropagated in vitro, were field evaluated in three different growing locations. Regardless of growing site, the quantitative variables with more discriminating value were essential oils yield, internode length, length of the longest branch, fresh weight, dry weight of leaf and stem, leaf/stem ratio, and leaf area. Based on the quantitative traits, oregano clones can be classified into four groups. From the observations based on botanical characteristics, it was determined that the evaluated clones belong to three different taxa: Origanum vulgare ssp. vulgare, Origanum vulgare ssp. hirtum, and Origanum x majoricum (hybrid). Within each group, the clones belong to the same taxon. 1. Introduction The genus Origanum belongs to the family Lamiaceae and includes more than 70 species, subspecies, varieties, and hybrids that are commonly found as wild plants in the Mediterranean areas [1]. This aromatic herb, mainly used as condiment, in liquors formulations, tomato sauces, baked goods, and salad dressing [2¨C10], is one of the most important aromatic spices cultivated in Argentina from the point of view of demand and acreage (80%) [11]. The main production areas are located in the provinces of Mendoza, C¨®rdoba, and San Juan [12] although there are smaller production areas in the northwestern regions of the provinces of Salta and Jujuy [10]. The local production of oregano is mainly for domestic consumption; however, in recent years a surplus production for export was registered. Despite this surplus production, the cultivation of oregano in our country is still affected by several problems. The oregano produced often does not have the best qualities to be considered a premium product for food because it is grown regardless of the variety, health, and the harvest and postharvest practices; in this situation, it is not possible to conserve a product free of contamination. Besides there is little taxonomic identification of the plant material used for cultivation; in fact, in our %U http://www.hindawi.com/journals/isrn.agronomy/2012/349565/