H Half-sib progeny test for selection of best parents for development of a synthetic variety of alfalfa

To evaluate general combining ability of alfalfa ecotypes of Azarbaijan province, Iran, by a polycross progeny test and selection of best parents for development of a synthetic variety, a field experiment was conducted in 2001 to 2007 cropping seasons, in East Azarbaijan Agricultural and Natural Resources Research Center, Tabriz, Iran. Twenty nine local ecotypes were collected from different Azarbaijan regions and polycross nursery was established including one improved variety-using a randomized complete block design with 12 replications, to insure the random mating in the polycross nursery. The 30 resulting half-sib families from polycross nursery were planted individually in pots and 30 days old seedlings were transplanted to field, and various traits were measured for three cropping seasons in a polycross test. The results of analyses showed large variation among ecotypes implying the efficiency of selection among their progenies. Based on general combining ability, especially for fresh and dry yield, Saattlou, Gharayonjeh, Almard, Legan, Baftan, Khajeh, Sivan, Ilan jouj, Dizaj Safar Ali, Khosrovang and Gharababa ecotypes were selected as best parents for development of a synthetic variety. The narrow–sense heritability values for fresh yield, dry matter, plant height, fresh leaf: stem and dry leaf: stem were estimated as 60%, 59%, 50%, 11% and 19%, respectively. Using selection intensity of 30%, an increase in fresh yield and dry matter by 3.2 and 1.58 ton ha-1 were estimated, respectively. This research is continued by combining 11 selected ecotypes to develop a synthetic variety.