Plant & Animal Genome VI Conference

P55

ASSESSMENT OF DIVERSITY AND IDENTITY OF FARMERS RICE VARIETIES USING MICROSATELLITE MARKERS

1. Philippine Rice Research Institute, Maligaya, Munoz, Nueva Ecija, Philippines
2. International Rice Research Institute, P.O.Box 933, 1099 Manila, Philippines

We assessed the diversity and identity of farmers varieties to determine the on-farm conservation strategies that may be adapted in 3 towns in Northern Philippines. DNA fingerprints of farmer's varieties representing irrigated lowland, rainfed and upland ecosystems were analyzed using 21 microsatellite markers. 184 samples (112 Philippine traditional, 65 modern, and 7 unknown samples) were collected from farmers in the 3 towns. Several samples were collected from 25 varieties in different farmers field. The varieties with the most number of samples are IR66 and Biniding (IR68). Molecular marker analyses indicate that many of the samples with the same variety name like the Biniding (IR68) and IR66 samples have different microsatellite allelic compositions. Some samples with different variety names also have very similar microsatellite allelic compositions. Very few of the samples collected in the farmers field with the same name have very similar allelic composition. Comparison of the farmers varieties with those derived from breeder seeds indicates a big divergence between the two samples. The results indicate a high degree of out-crossing of farmers varieties and/or the mis-naming of several varieties. Continuous selection by both farmers and breeding institutions in the production of seeds seemed to contribute to the increased divergence of breeders and farmers seed materials. The farmers varieties also represent a genetically diverse set of material.