Abstract
Foeniculum vulgare L. (fennel), a member of the Apiaceae family, is a widely cultivated spice plant valued for its aromatic fruits and medicinal properties. This study aimed to evaluate the agro-morphological characteristics, yield potential, essential oil content and components, as well as elemental profiles of twenty genetically diverse fennel genotypes under identical agro-climatic conditions during the 2019 and 2020 growing seasons. Significant phenotypic variation was observed among the genotypes, with fruit yields ranging from 183.78 to 1682.77 kg/ha. Essential oil content varied between 1.80% and 4.11%, with Ames23130 and Ames30693 genotypes exhibiting the highest oil yields. Also, essential oil yield values were found between 3.92 and 55.74 L/ha, and Ames23130 genotype had the highest essential oil yield. Gas chromatography-mass spectrometry (GC-MS) analysis identified 17 essential oil components, five of which trans-anethole (54.14-90.44%), estragole (2.38-28.75%), p-cymene (0.10-39.63%), limonene (0.13-7.94%), and α-fenchone (0.47-8.44%) were classified as major components. Among these, trans-anethole consistently dominated across all genotypes and both years, reflecting a stable chemotypic profile. Elemental analysis performed via inductively coupled plasma optical emission spectrometry (ICP-OES) revealed that fennel fruits are rich in potassium, calcium and magnesium, with negligible levels of toxic metals such as cadmium and lead, affirming the samples' nutritional quality and food safety. Cluster analysis grouped the genotypes based on integrated yield, phytochemical, and mineral traits, with Ames23130 emerging as the most promising genotype for both fruit and essential oil production. Additionally, PI649471 and NSL6409 stood out for their distinct essential oil profiles, while PI414189 was notable for its superior potassium accumulation. The PCA analysis showed 42.9% of total variation, and correlation analysis revealed that highly significant positive correlation was found between Mn and Ca mineral contents with r = 0.749** These findings provide valuable insights for fennel breeding programs and support the selection of elite genotypes for both commercial cultivation and functional food applications.