| The relationships of the M and Mu genomes
of Aegilops Masatake TANAKA Kihara Inst. Biol. Res., Yokohama City Univ. Yokohama, Japan The genome constitutions of the 2x species of Aegilops comosa (incl. heldreichii) and Ae. uniaristata were established as MM and MuMu, respectively, by KIHARA (1937). Recently, KIMBER et al. (1983) have proposed the genome symbol of Ae. uniaristata for Un, namely the genome of Ae. uniaristata is comletely different from that of Ae. comosa from the results of meitotic chromosome pairing configurations in triploid, tetraploid and pentaploid hybrids involoving M and Mu genome species. However, we have cytological and morphological evidences for their relationships. The high frequencies of pairing have been observed in F1 and BF1 hybrids between Ae. comosa. heldreichii and uniaristata by KIHARA & YAMADA (1942) and YAMADA & SUZUKI (1941), as shown in Table 1. From the data obtained, it can be said that in the F1 plant (MMu) with comosa plasma, gamete with Mu genome is lethal. On the basis of the morphological analysis, these species are regarded as the collectives as shown in Table 2. Accordingly, it can be concluded that the M and Mu genomes were derived from a common genome constitution. |