Some Biochemical and Morphological Characteristics, and Antioxidant Activities in Watercress (Nasturtium officinale L.)

In this study, the variation between five populations (Kaleybar, Azarshahr, Urmia, Naghadeh and Doroud) of Iranian Watercress were investigated based on morphological traits and biochemical characteristics such as total antioxidant capacity, total phenol, total flavonoid and vitamin C. The results showed that there was significantdifferenceamongpopulations for all traits except stem diameter. According to the results, Kaleyber (East Azerbaijan) and Urmia (West Azerbaijan) accessions exhibited the highest and the lowest antioxidant capacity, respectively. The results of the correlation coefficient indicated that, leaf length had significantly positive correlation with some characteristics such as leaflet length, internode distance, stem diameter, total phenol and total flavonoid, and total phenol and total flavonoid with antioxidant capacity. Factor analysis showed that the first forth principle components explained 84.69% of the variation. The results of cluster analysis showed, studied accessions were divided into three sub-clusters, which indicates the diversity among accessions is high. There was a great difference between Kaleybar and Azarshahr accessions based on cluster analysis. The obtained results showed that there was high diversity between watercress populations based on morphological and biochemical traits. Also, watercress has a high level of antioxidant activity and Kaleybar population may be considered as the population with the highest antioxidant activity among tested populations.