The effect of CuO nanoparticles and irrigation intervals on antioxidant responses, yield components and essential oil content inFoeniculum vulgare Mill.

Eryngium caucasicum from the Apiaceae family, is native to the northern regions of Iran and has significant medicinal and nutritional properties. This paper has provided detailed morpho-anatomical characteristics of the leaves, peduncles, leaf tail, stem, and roots of Eryngium caucasicum by bright-field light microscopy. Also, the amount of phenol, flavonoid, and antioxidant activity with a spectrophotometer and the analysis of essential compounds of the aerial part with GC and GCMS have been presented. Morpho-anatomical features include the dicot-like leaves with palmate venation, isolateral mesophyll with palisade tissue on the upper and lower regions of the leaf, and much reduced spongy parenchyma; characteristic arrangement of the mechanical collenchyma tissue, especially in leaves; and characteristic wrinkles in the leaf cuticle. The stem and peduncle with longitudinal ribs contain collenchyma; there is a presence of aerenchyma in the peduncle and root; calcium oxalate druses and secretory channels in all the studied plant parts; and an absence of sclerenchyma in all investigated parts of the plant. The aerial parts of E. caucasicum had 37% essential oil, 53.9 mg of flavonoids per gram of dry matter, 48.79 mg per gram of dry matter, and 62.97 percent antioxidant activity. The main compounds in the essential oil of the aerial part include Piperitone (48.78%), ß-Sesquiphellandrene (12.64%), and (Z)-Falcarinol (7.85%), and (Z) ß-Farnesene (6.36 percent).