CHROMOSOME TRANSLOCATIONS IN WILD POPULATIONS OF TETRAPLOID EMMER WHEAT IN ISRAEL AND TURKEY

Translocation frequencies (as compared to the standard chromosome arra ngement typified by that in 'Chinese Spring) in 9 or more genotypes fr om each of 15 populations of Triticum dicoccoides in Israel were deter mined. Data also were obtained from 2 genotypes of the southernmost po pulation (Jaba). A single population from Turkey was also investigated . There were 119 genotypes with translocations in the sample of 171 ge notypes investigated (70%). The frequency of translocations in differe nt populations varied from 0.27 to 1.00, and all populations had 1 or more genotypes with one or more translocations. Some populations such as Qazrin appeared to be homogeneous for translocations, but most popu lations were heterogeneous. A sample of 17 genotypes from 12 of the po pulations were crossed with the Langdon D-genome disomic substitutions to determine the identity of the chromosomes involved in the transloc ations. There were nine genotypes with translocations and with the exc eption of a 2A/2B translocation, none of them involved the same chromo somes. The B-genome chromosomes were involved in translocations more f requently than the A-genome chromosomes. Translocation frequencies (TF ) of the various populations were correlated with environmental variab les, primarily with water availability and humidity, and possibly also with soil type. In general, TF was higher in peripheral populations i n the ecologically heterogeneous frontiers of species distribution tha n in the central populations located in the catchment ar ea of the upp er Jordan valley.