J Syst Evol ›› 1995, Vol. 33 ›› Issue (3): 230-239.

• Research Articles •

Studies of Karyotypes of Ranunculus cantoniensis Polyploid Complex and Its Allied Species

Liao Liang, Xu Ling‐ling, Chen Ye, Fang Liang

• Published:1995-05-10

Abstract: Ranunculus cantoniensis DC． polyploid complex was proposed by Okada． In order to clarify the structure of the ployploid complex，it is necessary to carry out a karyotype study on the complex and its allied species from China，where is the main distribution region of the complex．The karyotype analysis followed Li et al．The ployploid chromosomes in the complex were arranged according to the length of chromosomes and the position of centromere．The experimental materials are listed and the vouchers are deposited in JJT and PE．The experimental results and essential points are as follow：Ranunculus trigonus Hand．- Mazz．was found to have two cytotypes，which are correlated with the plant height．The short plant population has the karyorype 2n=2x=16=4m+6sm+6st(2SAT)，while the high plant one has the karyotype 2n=2x=16=4m+2sm+10st (2SAT)．The two karyotypes are first reported． Ranunculus silerifolius Lévl．was reduced to asynonym of Ranunculus cantoniensis DC.by L．Liou in 《F1．Reip．Pop．Sin》Vol．28．According to the characteristic of their chromosomes and morphology of experimental materials in the study，we suggest that the Ranunculus silerifolus Lévl． be treated as an independent species．The karyotype (2n=2x＝16=6m+2sm+8st) of Ranunculus chinensis Bunge，from Beijing，are almost entirely similar to that from Japan except that satellites are not found．The karyotype of Ranunculus silerifolius Lévl．(2n=2x=16=6m+2sm+6st+2t) in Guizhou Province of China is similar to the Mastuyama-type or Mugi-type of Ranunculus silerifolius in Japan．The karyotype(2n=4x=32=4m(a)+2m(b)+2sm(b)+4t(SAT)(c)+4st(d)+2m(e)+2sm(e)+2sm(f)+2st(f)+4st(g)+2st(h)+2m(h)) of Ranunculus cantoniensis DC．from Jiangxi Province of China is similar to the Kushikino-type in Japan. It consists of two different genomes. One of them is similar to the that of Ranunculus silerifolius (2x) or Ranunculus chinensis (2x) reported in the paper. The other is the genome named “short m –type”, which must have a pair of satellite chromosomes, No. 11 or No. 12, and a pair of “short m-type” chromosomes, No.16.The karyotype (2n=5x=40=3m(a)+2sm(a)+2st (b)+3sm(b)+2t(c)+3t(SAT)(c)+5st(d)+sm(e)+5sm(f)+5st(g)+5m(h)), of Ranunculus vaginatus Hand. -mazz. which is first reported, is basically similar to that of Ranunculus siebodii Miq. (2n= 6x= 48= 6m(a) +2st (b) +4sm(b)+4t (SAT) (c) +2st (SAT)(c)+6st(d)+6m(e)+6sm(f)+6st(g)+6m(h)) except ploid level and the morphology of two taxa is also similar to each other. They consist of two or three different “short m-type”chromosome sets respectively. We think that Ranunculus vaginatus has probably originatedfrom the hybridization between R. sieboldii (6x) and an unknown allied tetraploid. It is probable that the members in the complex and its allied species became related through the genome called “short m-type” (Plate 2) and thus a polyploid pillar complex formed.