Morphological evaluation of Tunisian garlic (Allium sativum L.) landraces for growth and yield traits

Despite the significance of garlic as a food product and high annual income, until now there are no local commercialized Tunisian cultivars with registered names, which lead to the lack of recommended varieties of high yielding. This work is aimed to create the first garlic gene bank collection in Tunisia, evaluate the variation, identify yield related traits and structure genetic diversity among them. Thirty six local garlic landraces from the main production regions of Tunisia were collected and recorded in the National Gene Bank of Tunisia database, then grown in a gene bank field for multiplication. The phenotypic diversity was conducted on the basis of fourteen quantitative characteristics add to flowering ability. High diversity among Tunisian garlic landraces was detected. The bulb weight and bulb diameter explain the most significant variation of the yield. The cluster analysis sorted the 36 genotypes into three main groups as cluster 1 (11 accessions), cluster 2 (20 accessions), and cluster 3 (5 accessions). However, the grouping of genotypes did not correspond with their geographic origin. The highest genetic distance was reported between NGBTUN442 and NGBTUN452, however NGBTUN429 and NGBTUN434 found to be most similar with the lowest dissimilarity.  Morphological traits need to be investigated overtime. This study is interesting since it presents the first creation of the garlic gene bank in Tunisia. The results will provide basis information for the efficient use of the local garlic germplasm and help breeders to easily select out the desirable materials.