Characterization of some garlic clones using morphological, cytological, molecular and Headspace GC/MS techniques

Abstract

Four different clones of garlic (Balady, EGA 3, EGA 4 and Growers clone) cultivated in Egypt were differentiated using morphological, cytogenetical, molecular and chemical characterization. Results of the morphological and cytogenetical characters analyses showed that there were considerable variations for all studied traits except for three; leaf width, stem diameter and chromosome numbers. Additionally, SSR (simple sequence repeats) and ISSR (inter simple sequence repeats) markers showed a high level of genetic variation among the four garlic clones. Moreover, Headspace Gas Chromatography and Mass Spectroscopy (HS GC/MS) was used for identifying and comparing the volatile constituents. The resulting peaks showed thirteen major constituents [prop-2-en-1-ol, 5-hexenal, trans-2-trans-7-nonadiene, 1-propene-3,3`-thiobis, 1-propene, 3-(methylthio), disulfide,methyl-2-propenyl, camphene, disulfide, di-2-propenyl, trisulfide, methyl-2-propenyl, diallyltetrasulphide, 2-vinyl-[4H]-1,3-dithiin, trisulfide, 1-trisulfide, di-2-propenyl, 1,3-dithiane and trisulfide, dimethyl ] in the four analyzed clones.It could be concluded from this study, that the percentage of active volatile constituents in each clone may be used as chemical markers to distinguish between these clones. Accordingly, HS GS/MS is a considerably simple and fast method that can be used for initial identification of all four clones under the same conditions using the above compounds. The analyses can be performed on both entire fresh or powdered plant forms.