Abstract: The systematic relationship has been quite confused among the species of Larix because of given the weak morphological differentiation between species. The phylogeny of Larix is still poorly known. The genetic structures of 5 species of Larix were analyzed in this paper. Using horizontal sliceable starch gel electrophoresis method, the variation at 8 allozyme loci coding for 5enzyme systems(AAT, IDH, DIA, PGM, SKDH) was examined in 5 species of Larix taxa across their range in current study. These species are Larix sibirica Ledeb, L. cajanderi Mayr, L. gmelinii Rupr, L. sukaczewii Dil and hybrid L. czekanowskii(L. gmelinii×L. sibirica). The result showed that the genetic distance of the 5 species of Larix is from 0.067 to 0.260, which was higher than that of intra-specific populations. The result also revealed the relationship between the 4 species Considering the morphological, biological and ecological characteristics of the 5 Larix species, the evidence of allozyme variability support the idea that L. cajanderi, L. gmelinii, L. sibirica and L. Sukaczewii are independent species.

Key words: Larix, genetic relationship, allozyme