2018, Vol. 6, Issue 1, Part B

author(s)
Marziyeh Allahdadi and Parisa Farzane

abstract
Nitrogen has a key role in proper growth and development of all crops including artichoke. In order to study the effect of different levels of nitrogen fertilizer on morphological and phytochemical characteristics of artichoke plant, an experiment was conducted in a randomized complete block design with three replications in Isfahan, Iran during 2014. Treatments were four levels of nitrogen fertilizer (0, 100, 150 and 200 kg N ha^-1) from urea source. The result showed that nitrogen application in higher levels improved the growth of artichoke but reduced total phenol, total flavonoid and antioxidant activity. The highest of leaf length (102 cm), number of leaves per plant (30), plant fresh weight (3494.33 g) and dry weight (804.67 g) was observed in 200 kg N ha^-1. Phytochemical characteristics of artichoke decreased by use of chemical fertilizer and The maximum amount of total phenol (99.36 mg GAE g^-1 DW), total flavonoid (1.30 mg QE g^-1 DW), DPPH free radical scavenging activity (90.96%) and reducing power (2.29) was observed in control treatment. Also, we have found a positive correlation between the total phenol, total flavonoid content and antioxidant activity in artichoke. Based on the results, in order to avoid negative effects of nitrogen on the quality of artichoke leaves, it is recommended to use 100 kg N ha^-1 when cultivating artichoke for its medicinal use.