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Karyotype Analysis in Lycoris rosea Traub et Moldenke


The  present paper embodies the results of a karyotypic analysis for the
species Lycoris rosea Traub et Moldenke.  The voucher specimen, J. Z. Lin 004 is pre-
served in the Herbarium of Hanchow Botanical Garden. The chromosome number in root
tip cells is found for the first time to be 22, and the karyotype is shown to be an asymme-
trical one with rod-shaped chromosomes. A photomicrograph, the karyotype and the idiog-
ram are shown in Figs. 1-2. According to Levan et aL.[5], the karyotype formula of the
species is 2n=22=22t. But based on the classification presented by Bose and Flory[1], the
karyotype formula should be expressed as 2n=22 =C22, and the chromosomes are all with
subterminal constrictions.
      If regarding 11 as the basic number and centric fusion as the major tendency of karyo-
type evolution as proposed by Inariyama[2], Stebbins[6], and Jones[3,4] in particular, L. rosea
would be considered as one of the most primitive species in Lycoris from point of view of
karyotype evolution. Reciprocal translocations and centric fusions would give rise to V-sha-
ped chromosomes. Consequently, the successive decrease in chromosome number may have
taken place in the speciation of the genus under discussion. Yet further evidence seems ne-
cessary for the verification of the speculation.


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