Delimitation of varietal groups in garlic (Allium sativum L) by morphologigal, physiological and biochemical characters

65 garlic cultivars from 25 countries have been investigated for morphological and physiological characters : clove number and disposition, presence or absence of a floral stem, number and size of inflorescence bulbils, clove dormancy, low temperature requirement for axillary bud differenciation, daylength threshold for bulb enlargement. In addition, enzymatic description was also performed. These characters allow the delimitation of 6 varietal groups in the Western world (Europe, Africa, America). These groups appear as homogeneous for isozyme characterisation with the 4 enzymes among 20 which appeared as polymorphic : esterase, phosphoglucomutase, malate dehydrogenase and diaphorase. Groups I and II share the same enzymatic formula. Groups III to VI are characterised by unique enzymatic formulae. The Asiatic cultivars which were investigated are not fully representative of the whole continent. However, 10 enzymatic patterns are encountered Two cultivars from Uzbekistan and Lebanon have the same isozyme formula as group V, although different for morphology and physiology. Ten clones among the 14 seed producing clones from central Asia and Moscow botanical garden share the same isozyme formula, the other 4 appear as isolated. None of these enzymatic formulae appears in the western world. Nine cultivars from Japan and Northern China, although heterogeneous for morphology, share the same isozyme formula, unknown in the Western world. Two cultivars from southern China and Taiwan (R.O.C.) have the same isozyme formula as occidental group III, a cultivar from Thailand is similar for morphology, physiology and isozymes to occidental group VI, and a cultivar from Indonesia has the same isozyme formula as occidental group I, and reminds it for morphology. The enzymatic groups roughly match the morpho-physiological groups, although less accurately and evidence the narrow genetic basis in cultivated garlic.