Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1994: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1992: ¥1,000,000 (Direct Cost: ¥1,000,000)
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Research Abstract |
Restriction map variation in two 5-6 kb chloroplast DNA regions of five diploid Aegilops species in the section Sitopsis and two wild tetraploid wheats, T.dicoccoides and T.araraticum was investigated with a battery of 4-cutter restriction enzymes. More than 250 restriction sites were scored, of which only seven sites were polymorphic in Ae.speltoides. No restriction site polymorphisms were detected in all the other diploid and tetraploid species. In addition, six insertion/deletion polymorphisms were detected, but they were unique or species-specific. Estimated nucleotide diversity (pi : Nei and Li, 1979) was 0.0006 for Ae.speltoides, and 0.0000 for all the other investigated species. In Ae.speltoides, none of Tajima's D (1989) were significant, indicating no clear deviation from the neutrality of DNA polymorphisms. Significant non-random association was detected for three combinations out of ten possible pairs between polymorphic restriction sites in Ae.speltoides. Phylogenetic relationship among all the plastotypes (Plastid genotype) suggested the diphyletic origin of T.dicoccoides and T.araraticum. A plastotype of one Ae.speltoides accession was identical to the major type of T.araraticum (T.timopheevi inclusively) . Three of the plastotypes found in the Sitopsis species are very similar, but not identical, to that of T.dicoccoides, T.durum and T.aestivum. Restriction fragment length polymorphisms in the five Aegilops species of Sitopsis section were investigated by using random nuclear DNA clones. Level of polymorphism in Ae.speltoides is as high as that of interspecific divergence between the other four species. Phylogenetic relationship obtained by this RFLP analysis agrees with with those of classical taxonomy based on morphology and RFLP analysis on chloroplast DNA.
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