PEDIGREE AND RAPD-BASED DNA ANALYSIS OF COMMERCIAL US RICE CULTIVARS

Pedigree information has traditionally been used to obtain estimates o f genetic variation, predict hybrid performance, and select parents fo r crossing in crop improvement programs, We have generated and compare d pedigree and randomly amplified polymorphic DNA (RAPD) data obtained from 26 elite cultivars and lines of rice (Oryza sativa L.) recommend ed for commercial production in Louisiana anti elsewhere in the USA, F or the RAPD analysis, 220 commercially available primers (10-mers) wer e evaluated fur their ability in distinguish pairwise combinations of the cultivars-lines that included four sets of full sibs, A total of 6 9 primers produced 92 polymorphic bands, 0.25 to 3.5 kb in size. Seven primers were identified that could differentiate all cultivars-lines. Genetic distances obtained from RAPD data were correlated with estima ted kinship coefficients, Within the RAPD or pedigree method, similar mean genetic distances were detected for long-and medium-grain cultiva rs. However, mean genetic distances based on pedigrees were significan tly greater than those based on RAPD data fur both grains types, Culti vars with the same maturity group or grain type mere generally placed together in cluster analyses based on either RAPD or known pedigree da ta, RAPD information can be used to establish genetic relationship amo ng commercial U.S. rice cultivers with unknown or unrelated pedigrees.