| c. Physiological characters [i] Shooting date : Early, intermediate and late shooting types were found in the strains of Ae. triuncialis. There was a marked tendency to late shooting in the strains from Iran, while early shooting types were found more often in the strains from Afghanistan. [ii] Seed fertility : The fertility of the samples from the original habitat in 1955 was much higher than that of those from the cultivation in the experimental field in Kyoto in 1956. The low fertility of the latter is probably due to the influence of the rain condition during the flowering time. [iii] Growing habit : 65 strains collected in 33 habitats from the different regions have been studied for growing habits in the experimental field in Kyoto. They were classified into 29 spring types, 23 intermediate types, and 13 winter types. 18 out of 22 strains from the Tehran region were perfect spring types, and 15 out of 19 strains from the Maimana region were intermediate or spring types, while, 7 out of 11 strains from the Tabriz region were winter types. However, mixed populations of spring and winter types were also found in the habitats near Tabriz in the Tabriz region, Iran, and also near Haibak in the Pul-i-Khumri region, Afghanistan. It is thought that the spring type is a natural mutation from the winter type. d. Origin of ssp. eu-triuncialis and ssp. orientalis. The origin of Ae. triuncialis presents one of the most puzzling problems. Ssp. eu-triuncialis is represented sp. var. typica, and ssp. orientalis by var. persica. Ssp. orientalis is distinguished by the characteristic such as barrel type disarticulation of ears. The studies of the karyotype of Ae. triuncialis were published by SENJANINOVA - KORCZAGINA (1932), and CHENNAVEERAIAH(1960). SENJANINOVA - KORCZAGINA established Ae. persica as an independent sub-species, based on her karyomorphological findings that var. persica had a karyotype composed of Cu-genome of Ae. umbellulata and C-genome of Ac. caudata, while ssp. eu-triuncialis had the karyotype composed of Cu-genome and one genome which is not identical with that of Ae. caudata. According to CHENNAVEERAIAH, however, ssp. persica has one set of chromosomes which corresponds to the Cu-genome, and the second set resembles C-genome. In ssp. eu-triuncialis he found also one set of chromosomes corresponding to Cu-genome, but he thought that the second set differs not only from the typical C-genome of Ae. caudata, but also from that of persica. Therefore, he concluded that there are Cu and C in the triuncialis complex. The barrel type disarticulation in a form of ssp. persica will be explained as the introgression from Ae. crassa, as suggested by ZOHARY and FELDMAN (1962). |
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