Rice Genetics IV - IRRI books - International Rice Research Institute

ABCDO. barthiiO. rufipogonO. longistaminataO. glumaepatulaO. meridionalisFig. 1. Schematic diagrams showing genetic diversity amongand within species of AA genome wild taxa based on isozyme(A), nuclear DNA restriction fragment length polymorphism(RFLP) (B), mtDNA RFLP (C), and cpDNA RFLP (D). (Redrawnfrom Akimoto 1999.)as perceived from previous studies, O. meridionalis (or O. meridionalis and O.longistaminata) is remote from other species that are distinct but relatively close toeach other. O. glumaepatula showed closer similarity with O. longistaminata inisozyme and with O. barthii in RFLP. In organellar markers, species difference wasdistinct except for O. glumaepatula. Strains collected from northern South Americatogether with those from Central America showed similarity with O. longistaminatain mtDNA, whereas those from the Amazon basin showed similarity with O. barthiiin mtDNA as well as in cpDNA. Genetic closeness between O. glumaepatula andboth African taxa was previously pointed out by Wang ZY et al (1992), Doi et al(1995), and Ge et al (1999) based on a smaller number of accessions. On the otherhand, similarity between some accessions of O. glumaepatula and O. rufipogon waspointed out by many authors, such as Dally and Second (1990), Doi et al (1995), andJuliano et al (1998). In Akimoto’s study (1999), 57 O. glumaepatula accessions, excludingapparently weedy or introgressed types, did not show similarity with O. rufipogon.Yet, O. glumaepatula is undoubtedly a heterogeneous species and its phylogenetic statusis still problematic.Evolution and domestication of rice 65