STUDY OF KARYOTYPES OF 3 SPECIES OF PINUS
Chang Hsiao-fang (Northeast Forestry College) Li Mau-xue (Peking University)
This paper reports the study of karyotypes of 3 species of pinus. The chromosome number of these species is 2n=2x=24, all metacentric. Based on the comparison of secondary constrictions, comparative length and L/S value, the authors suggest that it be more reasonable to cla-ssify Pinus takahasii as a species. By comparing karyotypes of Pinus sylvestris, P. takahsii, P. sylvestris var. sylvestrformis, P. densiflora (Shandong Province), the authors have discovered that the variations of the location of secondary constrictions are related to their geogra-ohical distributions.