WHEAT PHYLOGENY DETERMINED BY RFLP ANALYSIS OF NUCLEAR-DNA .3. INTRASPECIFIC AND INTERSPECIFIC VARIATIONS OF 5 AEGILOPS SITOPSIS SPECIES

The level of intra- and interspecific variations on nuclear DNA in fiv e Aegilops species of the Sitopsis section were investigated using res triction fragment length polymorphism (RFLP) analysis. A total of 18 a ccessions, i.e. 7 of Ae. speltoides, 3 of Ae. longissima, 2 of Ae. sea rsii, 3 of Ae. sharonensis and 3 of Ae, bicornis, were used. One acces sion each of Triticum aestivum, T. durum, T. urartu and Ae. squarrosa was included as reference material. Five enzymes and 20 probes were us ed. Among the five Sitopsis species studied, Ae. speltoides had the la rgest intraspecific variation (pi = 0.061), which was as high as the i nterspecific variation observed among the other four species. The sect ion Sitopsis was divided into two distinct groups: one containing only Ae. speltoides and the other, Ae. longissima, Ae. searsii, Ae. sharon ensis and Ae. bicornis. This grouping by RFLP analysis is in agreement with the taxonomical classification of the subsections.