Estimation of Genetic Parameters and General Combining Ability of Sainfoin Landraces with Respect to Forage Yield

Sainfoin in believed as an important forage crop regarding its suitable agronomical characteristics and feeding livestock. Evaluation of general combining ability is a critical preliminary stage before selection of suitable parent and production of synthetic varieties. Thirty six sainfoin landraces which have been collected from different parts of Iran were grown in 2000 in a randomized complete block design (RCBD) with 24 replications as a polycross nursery. The resulting polycrosses were sown in 2001 in a triple lattice design. Characters such as fresh forage yield per plot based on unit length, fresh forage yield per plant, and dry forage yield for each cutting stage and for the whole season were measured. Also a yield index for the two first cuttings and forage palatability for the second cutting were determined. Results showed that there was no significant difference between partial blocks within each replication and therefore data was analyzed based on RCBD. High heritability was observed for forage palatability, yield index, and fresh forage yield per plant. So selection can be made to improve forage yield and palatibility in sainfoin. In terms of general combining ability, six landraces for fresh forage yield, six landraces for dry forage yield, nine landraces for yield index, and ten landraces for palatibility showed high estimates. The lanraces having highest amounts of general combining ability for each variable can be used as suitable parents to produce synthetic varieties of sainfoin.