抄録
In 1949 young F1 seedlings of 9 penta.ploid crosses between A1;elace barbceta (n=14) and some culti-vated varieties of Ave, na sativa (n=21) as well as A. nuda(u=21) vrere treated with 0.05% colchi cine solution according to L., b. CUA's method(951). It was already reported that pentploid Aveu hybrids were highly sterlie (I:ISHlYAltlA 1929, 19 39). Howeveir, same of the: treated hybrids were found to exhibit different degrees of fertility. It was further noted that different ears in one and the same plant often showed a great var'iation in fertility ranging from 'highly fertile to completly sterile (Table 2) . In the present case it is beyond doubt that 'che fertile plants would be amphidirp lojds of pentaploid hybrids. A preliminary investigation rewaled that some seedlings from fertile plants hd 70 omatic chromosomes as expected. Basing on the degree of fertility the auth=0f elas-sified the treated plants as 4la plants (high fer-t, ile), 2 u:1a mixoploids (either low in fertility or having soine ears that, are highly fer'ti', , e but the others age sterile) and 2n plants (nearly colenpietely sterile-). The resits are given in Tables I and . In this work 6 different amphidiploids (dctoploid oat) were succesefully obtines and the offspring ar, e novT'grow. ing vigorqusly in the field.
