Morphometric and colour characteristics of garlic accessions (Allium sativum L.) in the Agricultural Institute of Slovenia

Garlic from the Alliaceae family is a vegetatively propagated bulbous crop with great morphological diversity. It is used worldwide as an important spice in cooking and in traditional medicine. Garlic accessions managed in the Slovenian Plant Gene Bank at the Agricultural Institute of Slovenia were studied on the basis of various morphometric and colour characteristics of the bulbs and cloves. A total of 49 garlic accessions were grown and evaluated in the experimental fields of Infrastructure Centre Jablje in 2023. Numerical descriptors included the bulb weight, height and diameter, the height/diameter ratio, the number of cloves, and clove size. Qualitative descriptors included ten UPOV descriptors related to the pseudostem (flowering stem), the bulb (size, ground colour of dry external scales, anthocyanin stripes on dry external scales, number of cloves), and the clove (size, colour of scales, intensity of colour of scales, anthocyanin stripes on scales, colour of flesh). Results have shown significant differences between the accessions in terms of the bulb size and colour parameters. The bulb weight ranged from 8.6-54.1 g, the bulb height from 26.5-45.8 mm, and the bulb diameter from 31.4-58.9 mm. The average number of cloves was 10 ± 3 and the weight of the cloves was 3.0 ± 1.2 g. The predominant bulb ground colours of dry external scales were white and yellowish white, 31 and 18 accessions, respectively. The clove colours of the scales were predominantly pink/purple, pink/purple/brown, brown, cream/pink, or cream, with anthocyanin stripes on the scales present in nearly 75% of the accessions. The highest coefficients of variation were observed for the bulb size (49.6%) and the clove size (39.6%) and the lowest for the height/diameter ratio (6.2%). The data obtained and the variability of the traits studied indicate that garlic accessions require further in-depth agromorphological, nutritional, and genetic analyses to identify the best candidates for future breeding proposals.