Morphological and Molecular Characterization of some Medicago species

George Tarabin
Germplasm Department, General Commission For Scientific
Agricultural Research (GCSAR)
Faculty of Agriculture, Damascus University,
2010

Abstract

Morphological characterization was carried out at Abu-Jarash Farm and Biotechnology Laboratory, Faculty of Agriculture, Damascus University during 2008-2010. Twenty samples belong to ten wild species and a cultivated one (control) were planted in randomized complete design (RCD).
The results showed that the control species M. sativa was superior to all species in germination earliness, however, the species M. truncatula, M. minima, M. turbinata and M. orbicularis were superior in delay flowering; all species superior in branching number except M. truncatula; M. scutellata and M. orbicularis superior in number of leaves per plant; M. minima, M. polymorpha, M. scutellata, M. orbicularis in flower stalks number; M. orbicularis in pods number. All species were superior in delay of total maturity except the M. polymorpha.
Positively significant correlations appeared between most of the studied characteristics. Molecular investigation revealed that all the primers have effectiveness in showing polymorphism, and they gave a total of 92 alleles with a polymorphic percentage of 100%. The number of bands for each primer varied from minimum 5 bands for the primer (ISSR34) to maximum 21 bands for the primer (ISSR-41) on average of 11.5 bands for each primer.
Cluster analysis of morphological characterization showed siginificant similarity between M. rotata and M. polymorpha, and between M. scutellata and M. turbinate, and higher differentiation between M. orbicularis and both M. rotate and M. intertexta, and that was confirmed by the molecular study which showed the highest degree of genetic similarity between M. rotata and M. polymorpha (0.77), followed by species M. sativa and M. truncatula (0.73); M. scutellata and M. turbinata (0.71), while it was low between M. orbicularis and both  M. rotata and M. intertexta (0.43). The results showed vast genetic diversity among the genus Medicago in Syria.