Welcome to Journal of University of Chinese Academy of Sciences,Today is

Previous Articles     Next Articles

Study on Karyotypical Variation and Differentiation in Populations of Pinus yunnanensis Franch.

YU Hong, HUANG Rui-Fu   

  • Received:1900-01-01 Revised:1900-01-01 Online:1998-05-10 Published:1998-05-10
  • Contact: YU Hong

Abstract:

Analyzed in the present paper was the karyotype in six populations (Pi ,P2,P3,
P4, P5, P6 ) of Pinus yunnanensis Franch. P1 is distributed in the central region of Yun-
nan, P2 in the southeast, P3 in tbenorthwest, P4(P. yunnanensis var. pygmaea (Hsüeh)
Hsüeh)in the centre, P5(P. yuunnanensis var. tenuifolia Cheng et Law)in the juncture of
southeastern Yunnan, northern Guangxi and southern Guizhou, and P6 is an introgression
population between P. yunnanensis Frach and P. kesiya Royle ex Cord. var. langbianen-
sis (A. Chev) Gaussen. The six populations had almost the same karyotypical formula, i.e.,
2n= 2x= 24 = 24m(6~10 SAT). All the karyotypes of the six populations belong to the
Stebbins' 1A. Therefore, no obvious variation was detected at general karyotype level in P.
yunnanensis, but there existed slight variation in relative length, arm ratio, number of sec-
ondary constrictions and their distribution among the six populations. The indexes of relative
length in the six populations are as follows: P1 = 16M2 + 6M1 + 2S; P2 = 14M2 + 8M1 + 2S;
P3 = 12M2 + 10M1 + 2S; P4 = 14M2 + 8M1 + 2S; P5 = 14M2 + 8M1 + 2S; P6 = 10M2 + 12M1
 + 2S. The nested analysis of variance shows that about 10% of the chromosomal variability
is attributed to the differentiation among populations and the remaining 90 % within popula-
tion.

Key words: Pinus yunnanensis Franch., Population, Karyotypical variation, Chromosome