Agro-morphological and phytochemical diversity of various Iranian fennel landraces
Introduction
The oldest evidence referring to medicinal plants usage traces back to sixty thousands years ago in Shanidar cave in Kurdistan (Lietava, 1992). Among medicinal plants Foeniculum vulgare known as fennel from Apiaceae family, is one of the oldest herbs. Bitter fennel subspecies (F. vulgare Mill. var. vulgare), possessing appealing flavor and beneficial medicinal effects, is cultivated as source species for the fennel derived drugs (Hornok, 1992). Bitter fennel, hereafter named just as fennel, is native to the Mediterranean areas also has been naturalized in many other regions. Fennel is a biennial or perennial herb up to two meters high and has feathery leaves and golden yellow flowers (Omid baigi, 2009, Guillen and Manzanos, 1994, Hornok, 1992). In human nutrition, every parts of this plant including seeds, foliage and roots can be used in different ways (Edoardo et al., 2010, Barros et al., 2010). Fennel pollen also is known as a popular spice (Kimberly and Jazmine, 2013). Fennel seed with its spicy odor and burning sweet taste has a special usage in condiments, perfumes and liqueurs industrials as flavoring reagent (Edoardo et al., 2010, Barros et al., 2010). In livestock industries, the significant improvement in chicks body weight and feed efficiency were obtained by addition of fennel seed to their feed (Teixeira et al., 2013, Mohammed and Abbas, 2009). From the aspect of medical cares, several studies have shown herbal drugs and essential oil of fennel has valuable antioxidant, anticancer, inflammatory, antibacterial, antifungal and analgesic activities (Diao et al., 2014, El-Awadi and Esmat, 2010, Singh et al., 2006, Lucinewton et al., 2005, Choi and Hwang, 2004, Elagayyar et al., 2001). Fennel essential oil is being added to perfumes, soaps and cosmetics, and several commercial pharmaceuticals are formulated based on it (Edoardo et al., 2010, Elagayyar et al., 2001). The main essential oil components of fennel are trans anethole, methyl chavicole (estragole), fenchone and limonene, and according to Akgiil and Bayrak (1988), the highest values of these components are exist in reproductive organs specially seeds. Trans anethole counts for the anise taste, serves as a pleasing aroma in food and perfumes, as well as an effective antiflatulence agent in herbal medicines (He and Huang, 2011, Pank et al., 2003, Guilled and Manzanons, 1996, Yaylayan, 1991). Methyl chavicole provides sweet taste, is mainly used in the perfume industry while limonene is used in resins and solvents, and fenchone is responsible for bitter and spicy taste of fennel and acts as a real antidepressant (Albert Puleo, 1980, Lawless, 1992, Sun, 2007, He and Huang, 2011). According to previous studies about essential oil components of bitter fennel, trans anethole content ranges from 0.1 to 78, methyl chavicole from 0.1 to 58, fenchone from 1 to 14 and limonene from 1 to 22% (Moghtader, 2013, Shahat et al., 2011, Aprotosoaie et al., 2010, Gulfraz et al., 2008, Stefanini et al., 2006, Bowes and Zheljazkov, 2005, Piccaglia and Marotti, 2001). The total world fennel seed production in 2012 was ∼830 thousands tones (FAO, 2012), and for use in different industries the demand for fennel seed and its essential oil in today’s world market is rapidly raising; this necessitates the need to develop elite cultivars with high yield (Dashora et al., 2003, Reichardt and Pank, 1993). In this way fennel needs more attention of researchers and the first step is gaining the knowledge of present diversity that can guide appropriate selection schemes, breeding programs and germplasm conservation (Judzentiene and Mockute, 2010).
Iran is one of the most important producers of fennel seed in the world (FAO, 2012) and in contrast to commercial cultivation of fennel, Iranian fennel landraces have never been comprehensively studied neither for seed and essential oil production nor for essential oil components. Fennel med quality is associated with seed yield, essential oil content and active components concentration. Fennel populations in Iran are scattered from Chabahar city (25 26°N and 60 61°E) on coastal line of Oman Sea to Mako city (40 39°N and 44 45°E) near Caucasia, from dry areas like Yazd city with 100 mm to humid areas like Talesh city with 2000 mm annual precipitation, from Bandar anzali city with −21 m to Fareydon shahr city with 2600 m altitude, from Zarine obato city with annual mean temperature 7 °C to Ahvaz city with 27 °C (Izadi Darbandi and Bahmani, 2011; www.meteogical.ir), accordingly Iranian fennels occupy very different habitats and due to adaptation to the local environments from long time ago, it is assumed each region has its own specific fennel landrace (Ramırez Valiente et al., 2009, Murray et al., 2004, Heywood, 2002); this subject has been proved morphologically (Bahmani et al., 2012a), genetically (Bahmani et al., 2012b: Bahmani et al., 2013) and cytogenetically (Sheidai et al., 2007). Among this diversity, classical breeding like screening and introduction of elite landraces and also identification of the best criteria as morphological markers to use in future yield improving breeding programs are being mentioned as the fastest, easiest and reliable way to develop elite fennel cultivars (Farsi and Baqheri, 2006, Zeinali Khanaqhah et al., 2004). In the way of having the best criteria to use in future yield improving breeding programs, finding the relationship between yield and its components, and also the relationship among yield components is the first priority (Ali et al., 2003, Choudhry et al., 1986). According to Al-Kordy (2000) in fennel the amounts of heritability for plant height, number of primary branch and seed yield were 0.758, 0.826 and 0.201, respectively. In bitter fennels the broad sense heritability for essential oil content and seed yield were reported as 0.46 and 0.63 by Izadi Darbandi et al. (2013) and 0.81 and 0.93, respectively by Patel et al. (2008). Heritability values of the most of important traits in bitter fennels are high and promising (Izadi Darbandi et al., 2013, Patel et al., 2008). Seed yield in fennel is positively associated with several characters such as plant height, number of branches and umbel number (Singh and Mittal, 2003). Piccaglia and Marotti (2001) explained that the number of inflorescences per plant and the biomass weight were significantly and positively related to the essential oil content (r = 0.651 and 0.569, respectively). Contrary to these findings, Cosge et al. (2009) showed that correlations between essential oil content with number of umbels and biological yield were weak (r = 0.011 and 0.009, respectively). In addition, Cosge et al. (2009) showed essential oil content was only correlated with thousand seed weight (r = −0.37), and seed yield strongly and positively was correlated with biomass weight (r = 0.91). Lal (2007) reported the positive and strong correlation between seed yield and essential oil content, also negative correlation between days to 50% flowering with seed yield and essential oil content. The correlation coefficient solely is not informative enough to explain the cause and effect relationships among the variables, because the association between two variables may reliant upon a third variable. The use of path analysis provides a reasonable explanation of observed correlations by modeling the cause and effect relations among the variables. Thus, it is possible to analyze the correlation coefficient of variables in the form of variance and covariance using path analysis (Okut and Orhan, 1993). Path analysis as a statistical method for cause and effect analysis in correlated variables system has been used frequently even in medicinal plants (Dalkani et al., 2011, Cosge et al., 2009, Lal, 2007, Bhandari and Gupta, 1991). Path coefficient is a standardized partial regression coefficient and measures the direct influence of a predictor variable on the dependent variable (Mohammadi et al., 2003, Steel and Torrie, 1980) and will allow separating the correlation coefficient into direct and indirect effects (Mohammadi et al., 2003). Unexplained effects are considered as residual effects. Path analysis is being used by plant breeders to understand the relationship between yield and its components in various crops (Kang et al., 1983). Increases in germplasm collections and availability of agro-biodiversity will decrease the threats of genetic erosion and enhance the probability of finding good landraces for introduction or useful traits as morphological markers for screening programs.
Till now there is no any comprehensive report on Iranian fennels in term of yield production, active composition concentration and identification of criteria for future breeding programs, so we decided to do this. The aims of this study were: (1) evaluation of agro-morphological diversity in Iranian fennels in two successive years, (2) evaluation of phytochemical diversity in Iranian fennels and try to find its diversity pattern, (3) introduction of the elite landraces based on seed yield, essential oil content and active components concentration, (4) identification of relationships between yield and its components, and (5) introduction of the best criteria to use in future yield improving breeding programs. The results of this study are useful for fennel researchers and rearers.
Section snippets
Plant material
Seeds of 50 landraces of bitter fennels (F. vulgare var. vulgare) in 2009 from different Iranian locations were collected and stored in refrigerator in 4 °C (Table 1 and Fig. 1).
According to Fig. 1-left, our experiment was including 50 fennel landraces from all over Iran. With closer glance to Fig. 1-right, it is clear that there are two main chain mountains in Iran: one of them known as Alborz Mountains, from northwest to northeast, separating Caspian Sea side from middle side of the country,
Analyses of variance
Significant differences were found for the various agro-morphological traits in the different fennel landraces (Table 2). These variations provide opportunities for incorporation of these landraces into breeding programs for mass selection or developing new breeding populations.
Due to the significant effect of landrace per year, the data was analyzed separately for first year (Table 3) and second year (and 4).
According to Table 2, Table 3, Table 4, the Iranian fennels had a wide phenological
Conclusion
Diversity of Iranian fennels provides opportunities for incorporation of them into breeding programs for mass selection or developing new breeding populations. According to phenological traits, Iranian fennels were divided into three groups of early, medium and late maturity. Late and medium maturity fennels had the higher amounts of traits related to vegetative and reproductive growth than early maturity ones. In term of seed yield, medium maturity fennels had a better performance, and in term
Acknowledgements
This research was supported by University of Tehran. Thereby we wish to thank University of Tehran and anonymous referees who provided useful comments for improvement of our article.
References (66)
Fennel and anise as estrogenic agent
J. Ethnopharmacol.
(1980)- et al.
The nutritional composition of fennel (Foeniculum vulgare): shoots, leaves, stems and inflorescences
LWT Food Sci. Technol.
(2010) - et al.
Antiinflammatory: analgesic and antioxidant activities of the fruit of Foeniculum vulgare
Fitoterapia
(2004) - et al.
Chemical composition: antibacterial activity and mechanism of action of essential oil from seeds of fennel (Foeniculum vulgare Mill.)
Food Control
(2014) - et al.
The inheritance of volatile phenylpropenes in bitter fennel (Foeniculum vulgare Mill. var. vulgare, Apiaceae) chemotypes and their distribution within the plant
Biochem. Syst. Ecol.
(2009) Medicinal plants in a middle paleolithic grave Shanidar IV
J. Ethnopharmacol.
(1992)- et al.
Population differences in juvenile survival under increasing drought are mediated by seed size in cork oak (Quercus suber L.)
For. Ecol. Manag.
(2009) - et al.
Chemical constituents: antifungal and antioxidative potential of Foeniculum vulgare volatile oil and its acetone extract
Food Control
(2006) Flavor technology: recent trends and future perspectives
Can. Inst. Food Sci. Technol. J.
(1991)- et al.
Comparative volatile oil composition of various parts from Turkish bitter fennel (Foeniculum vulgare var. vulgare)
Food Chem.
(1988)
Relationship among yield components and selection criteria for yield improvement in winter rapeseed (Brassica napus L.)
Pak. J. Bot.
Mother plant selection in local germplasm of fennel Foeniculum vulgare Mill
Ann. Agric. Sci.
Changes in composition and antioxidant and antimicrobial activities of essential oil of fennel (Foeniculum vulgare Mill.) fruit at different stages of maturity
J. Herb Spice Med. Plants
The chemical profile of essential oils obtained from fennel fruits (Foeniculum vulgare Mill.)
Farmacia
Determination of interrelationships among phenotypic traits of Iranian fennel (Foeniculum vulgare Mill.) using correlation, stepwise regression and path analyses
J. Essent. Oil Bear. Plants
Assessment of genetic diversity in Iranian fennels using ISSR markers
J. Agric. Sci.
Assessment of the genetic diversity in iranian fennels by RAPD Markers
J. Herb Spice Med. Plants
Morphological and chemical evaluation of fennel (Foeniculum vulgare var. vulgare Mill.) populations of different origin
J. Essent. Oil Res.
Variation and association analysis in coriander
Euphytica
Optimization of water extraction of fennel seeds
J. Chem. Technol. Metal.
Essential oil yields and quality of fennel grown in Nova Scotia
Hortscience.
Path coefficient analysis of yield and yield components in wheat
Pak. J. Agric. Res.
Some phenotypic selection criteria to improve seed yield and essential oil percentage of sweet fennel (Foeniculum vulgare Mill. var. Dulce)
Tarim Bilimleri Dergisi
Correlation and sequential path analysis in ajowan (Carum copticum L.)
J. Med. Plant Res.
Combining ability analysis in varietal crosses of fennel (Foeniculum vulgare Mill.)
Indian J. Genet. Plant Breed.
Screening the essential oil composition of wild Sicilian fennel
Biochem. Syst. Ecol.
Physiological responses of fennel (Foeniculum vulgare Mill.) plants to some growth substances
J. Am. Sci.
Antimicrobial activity of essential oil from plants against selected pathogenic and saprophytic microorganisms
J. Food Prot.
The effect of date of sowing and plant spacing on yield of seed and volatile oil of fennel (Foeniculum vulgare Mill.)
Pharmazie
Principles of Plant Breeding
A contribution to study Spanish wild grown fennel (Foeniculum vulgare Mill.) as a source of flavor compounds
Chem. Microbiol. Technol. Lebensm.
A study of several parts the plant Foeniculum vulgare as a source of compounds with industrial interests
Food Res. Int.
Cited by (36)
Agro-morphological and phytochemical studies of spearmint landraces (Mentha spicata L.) in Iran
2022, Industrial Crops and ProductsCitation Excerpt :landrace M9 in the third group of cluster analysis classification had high values of morphological characteristics. Other researchers have reported similar results on biomass yield variability among different landraces of MACs, such as fennel (Bahmani et al., 2015), cumin (Moghaddam and Ghasemi Pirbalouti, 2017), thyme (Heydari et al., 2019), M. longifolia (Moshrefi Araghi et al., 2019) and guar (Meftahizadeh et al., 2019). Therefore, it can be concluded that where there is parity of climatic conditions and cultivation methodology, diversity in morphological traits can be attributed to genetic characteristics within the plant (Heydari et al., 2019).
Apiaceae essential oils and their constituents as insecticides against mosquitoes—A review
2021, Industrial Crops and ProductsVariability, association and path analysis of centellosides and agro-morphological characteristics in Iranian Centella asiatica (L.) Urban ecotypes
2021, South African Journal of BotanyEssential oil and chemical composition of wild and cultivated fennel (Foeniculum vulgare Mill.): A comparative study
2020, South African Journal of BotanyCitation Excerpt :Moreover, Shahat et al. (2012), who have analyzed the phytochemical profile of wild and cultivated fennel, found that cultivated plants showed higher percentages of α-pinene (32.82%), ß-pinene (2.09%), fenchone (5.91%), estragol (15.33%), myrcene (1.57%) and camphene (0.51%) while the wild plants showed much higher level of limonene (84.49%). These variations may be related to the combined effect of many agents comprising genetic factors and geographic origin as reported by several studies (Bahmani et al., 2015; Gholami Zali et al., 2018). The phytochemical profile of the essential oils extracted from wild and domesticated fennel seeds displayed quantitative rather than qualitative differences.