| Wild tetraploid wheats from West Iran cytogenetically
identical with Israeli T. dicoccoides Judith DAGAN and Daniel ZOHARY Laboratory of Genetics, The Hebrew University, Jerusalem, Israel Two samples of wild tetraploid wheats were collected by us in the western flanks of the Zagros Mountains. Iran (Ilam area, approx. 100 km S.W. of the town of Kermanshah). Morphologically and ecologically both collections fit very well the ranges described by HARLAN and ZOHARY (1966) for the "Turkish-Iraqui race" of T. dicoccoides. The two Iranian forms were crossed with (i) an Israeli dicoccoides tester line as well as T. durum. (ii) a representative of the T. timopheevi- T. araraticum cytogenetic stock. The following lines were used in the crossing program and the results obtained on chromosome pairing and on fertility of the F1 hybrids are set up in Table 1. No. 6690: Wild tetraploid wheat, 50 km southeast of Shahabad on road to Ilam, Kermanshah District, Iran. No. 6691: Wild tetraploid wheat, 40 km southeast of Shahabad on road to Ilam. No. 6256: T. dicoccoides; Safad Rosh-Pinna road. Eastern Galilee. Israel. No. N163: T. durum variety Nursit 163, A standard Israeli durum cultivar. No. 6284: T. dicoccoides var. nudiglumis, Handren Dagh, North Iraq, Coll. J. B. GILLETT. This is the Iraqi line used by L. SACHS (1953) in his crosses with T. timopheevi. It served as our representative of the timopheevi-araraticum stock. It is clear from the data presented in Table 1 that the wild Iranian wheats are fully interfertile with the Israeli dicoccoides stock. Chromosome pairing is normal and the presence in some combination of one or two translocation quadrivalents resembles very much the inter-varietal chromosomal variation found among various Israeli dicoccoides lines or different durum cultivars. In contrast, hybrids between the two Iranian lines and the representative of the timopheevi-araraticum stock manifest a drastic reduction of chromosome pairing and strong sterility. Our finds compliment the previous report of RAO and SMITH (1968) who discovered wild wheats cytogenetically similar to the Israeli T. dicoccoides among J. R. HARLAN collections from southern Turkey. This extend the geographic range of wild forms belonging to this stock to the southeast end of the Fertile Crescent arc. It is clear from finds that both dicoccoides and araraticum cytogenetic types occur sympatrically in southern Turkey, northern Iraq and western Iran, and that ecologically both occupy the oak (Quercus brantii) park-forest belt of this region. Furthermore, morphologically these sympatric wheats are embarrassingly similar, and RAO and SMITH also found a cytogenetically bridging form, interfertile with testers of both stocks. Obviously, we need a further clarification of the spatial and genetic relationships between wild tetraploids in Armenia and Kurdistan. But the data available already make it necessary to revise the concept of the place of domestication of dicoccum wheats. Contrary to the earlier proposal of HARLAN and ZOHARY (1966), Palestine and southern Syria can not any more be regarded as the sole location in which emmer domestication took place. The north and the northeastern segments of the Fertile Crescent arc become candidates as well! Literature Cited HARLAN, J. R. and D. ZOHARY 1966. Distribution of wild wheats and barleys. Science 153 : 1074-1080. RAO, P. S. and. E. L. SMITH 1968. Studies with Israeli and Turkish accessions of Triticum L. emend. var. dicoccoides (KORN) BOWDEN. Wheat Inform. Serv. 26 : 6-7. SACHS, L. 1953. Chromosome behaviour in species hybrids with Triticum timopheevi. Heredity 7 : 49-58. (Received September 14, 1970) |