Agro-morphological and phytochemical diversity of various Iranian fennel landraces

• Iranian fennels are classified as early, medium and late maturity landraces.
• Medium maturity fennel landraces have higher essential oil yield.
• Trans anethole chemotypes are from arid areas of eastern Zagros and southern Alborz.
• Stragole chemotypes are from humid areas of western Zagros and northern Alborz.
• Fenchone chemotypes are late maturity landraces from humid area of northern Alborz.
• Morphological markers to improve seed yield and essential oil content are not same.

Fennel is used for various purposes in medical, cosmetic and food industries and Iran is one of its main producers. In this study agro-morphological and phytochemical diversities of Iranian fennel landraces were assessed. According to phenological properties, Iranian fennels were classified as early, medium and late maturity. Based on two years data, late and medium maturity fennels had the higher amounts of vegetative and reproductive traits. In term of seed yield, medium maturity fennels had a better performance, and in term of essential oil content medium and late maturity fennels had the highest values. With considering essential oil yield the highest values were related to medium and late maturity landraces. According to GCMS analysis, in essential oil of the studied Iranian fennels, trans anethole content ranges from 1.24 to 88.45, methyl chavicole from 0.22 to 59.1, fenchone from 1.22 to 14.74 and limonene from 5.5 to 15.71%. Trans anethole chemotype landraces were belonged to arid areas of eastern Zagros and southern Alborz; methyl chavicole chemotype landraces to humid areas of western Zagros and northern Alborz; fenchone chemotype landraces to late maturity landraces from humid area of northern Alborz; and he highest limonene contents to landraces from areas with mediocre altitude in north of Iran. Based on path analysis, as morphological markers to improve seed yield, negative selection of days to 50% flowering and positive selection of weight of dry biomass, and to improve essential oil contents positive selection of days to 50% flowering severely are highly recommended.