| Nuclear DNA content of Einkorn wheat Y. FURUTA, T. HAJI and K. NISHIKAWA Laboratory of Genetics, Faculty of Agriculture, Gifu University, Kakamigahara, Gifu 504, Japan Information on DNA content of nucleus has been become indispensable for consideration of phylogeny of wheat. With regard to DNA content of nucleus each species of Triticum and Aegilops had been represented with a few varieties or strains in most of the earlier works. Our recent extensive study of DNA content of nucleus including 33 strains of Dinkel wheat, 33 of Ae. squarrosa and 38 of three species of Sitopsis (Ae. speltoides; 18, Ae. longissima; 10and Ae. bicornis; 10) has revealed, however, two remarkable facts as descrived below; (1) there is no difference among subspecies or cultivars of Dinkel or hexaploid wheat and it is equal to the sum of its parental species, (2) on the contrary, there are considerable intraspecific as well as interspecific variations in diploid ancestral species of polyploid wheat. So it is of great significance to evaluate not only interspecific but also intraspecific variation in DNA content of nucleus. Forty one strains of Einkorn or diploid wheat were subjected to Feulgen-microspectrophotometrical measurements. Of these, 39 strains were kindly provided for the present study from The Plant Germ-Plasm Institute, Kyoto University. Measurement was performed by Mendelsohn's two-wave length method (FURUTA et al. 1974). Ten nuclei of pollen tetrads were measured in each of four replicated preparations. Mean value, standard error and relative value to T. monococcum cultivar "Early" are shown in Table 1, together with their sources. Significant differences were found among strains within three varieties, var. monococcum. var. aegilopoides and var. thaoudar while no difference was found among three varieties. It is summarized that Einkorn wheat resembles to two other diploid ancestors of hexaploid wheat in variability of nuclear DNA content. Variability and its significance in wheat evolution will be discussed elsewhere in detail. Literature Cited FURUTA, Y., K. NISHIKAWA, and T. TANINO 1974. Stability in DNA content of AB genome component of common wheat during the past seven thousand years. Japan. J. Genetics 49: 179-187. |