CHROMOSOME NUMBERS OF SOME SOUTHWEST ASIAN SPECIES OF ASTRAGALUS AND OXYTROPIS (LEGUMINOSAE)

Abstract

To test the reliability of the hypothesis that chromosome number is a reliable character for the separating of Astragalus into 2 phylogenetic lines and in the hope that some hint of the relationship of New and Old World species of Astragalus might be obtained, 70 additional spp. of Astragalus and 9 spp. of Oxytropis were counted. Spp. counted were mainly from southern U. S. S. R. and Iraq but a few were from Egypt, Europe and the U. S. A. The counts consistently demonstrate that Old World spp. are based on an 8-chromosome series which shows considerable polyploidy while New World spp. have n = 11, 12 or 13 and no polyploidy.