Varietal evaluation of chamomile (Matricaria chamomilla L.) for biometrical, yield and quality traits under the conditions of the Plovdiv region, Bulgaria

Chamomile (Matricaria chamomilla L.) is one of the most widely cultivated and used medicinal and aromatic plants worldwide. The objective of the present study was to evaluate the varietal differences in biometrical, yield, and quality traits of chamomile grown under the agroecological conditions of the Plovdiv region, Bulgaria. The investigation was conducted during the period 2023–2025 and included three chamomile varieties: Bona, Degumille, and Comune. The experiment used a randomized block design with four replications and a plot size of 15 m². The results revealed significant differences among the studied varieties with respect to the evaluated traits. The Degumille variety was characterized by the greatest plant height (59.0 cm) and the largest flower diameter (2.67 cm). The Comune variety showed superior performance in terms of stem diameter (0.71 cm), number of branches per plant (8.1), fresh flower weight per plant (5.40 g), fresh flower yield (2235 kg ha-1), and essential oil yield (9.45 kg ha-1). The highest essential oil content (0.54 %) and the greatest number of flowers per plant (25.2) were recorded for the Bona variety. The extraction yield varied considerably among the varieties, ranging from 190.4 kg in Bona to 229.4 kg in Comune. Varietal differences affect chamomile productivity and the oil yield. Correlation analysis found a negative relationship between essential oil content and yield components (r = –0.726 with fresh flower yield), suggesting a trade-off between biomass accumulation and oil concentration. Keywords: chamomile, agronomy, variety, yield, essential oil