The effect of domestication on seed yield, essential oil yield and antioxidant activities of fennel seed (Foeniculum vulgare Mill) grown in Moroccan oasis

Abstract

The objective of this study is to clarify, for the first time in Morocco, the impact of culture on seed yield, growth parameters, yield and antioxidant activity of seed essential oils obtained from wild and cultivated fennel. The cultivation test was installed according to the principles of organic agriculture in a parcel at the oasis of Oukhite South East of Morocco under a completely randomized design with three replications. The agro-morphological characteristics were evaluated during two successive years (2014 and 2015). The results showed that fennel produces more of seed and total dry matter under culture conditions and both are more important in second year. The best performance of seed yield and total dry matter are 20.53 qx/ha and 199.79 qx/ha respectively. Domestication has not improved the yield and the antioxidant activities of fennel seed essential oils. In fact, wild fennel presented an essential oil yield significantly high (3.67%) compared to cultivated fennel (2.13%). For both applied tests DPPH and reducing power, essential oil obtained from wild plant presented the most important antioxidant power (IC₅₀:10.62 ± 0.33 and 29.49 ± 0.52 mg/mL) compared to that extracted from cultivated plant (IC₅₀:13.08 ± 0.34 and 32.30 ± 0.02 mg/mL). However, fennel cultivation is promising. It will permit to achieve interesting seed yields and may be good alternative to safeguard this species as well as to be used as an antioxidant natural source.