BIOSYSTEMATIC STUDIES ON ALLIUM L.Ⅰ.A STUDY ON KARYOTYPES OF 6 SAMPLES OF ALLIUM L.

The cytological features of 6 samples belonging to 5 species of Allium L. are analysed in this paper. The karyotypes formulae of these species are as follows: A. prattii C. H. Wright apud Forb. et Hemsl. (Ⅰ. Ⅱ.), Ⅰ. K(2n)=2x=16=9m+1m(SAT)+4sm+2st, Ⅱ. K(2n)=2x=16=10m+5sm+1sm(SAT); A. paepalanthoides Airy-Shaw: K(2n)=2x=16=14m+2sm+3B; A. plurifoliatum Rendle: K(2n)=2x=16=14m+2sm+1B; A. tubiflorum Rendle: K(2n)=2x=16=12m+2m(SAT)+2sm; A. omeiense Z. Y. Zhu: K(2n)=2x=22=2m+18sm+2T(SAT). All of investigated samples are diploid. The cytological results revealed a basis chromosome number of x=8 in all the investigated samples except A. omeiense Z. Y. Zhu. The chromosome numbers and karyotypes of A. plurifoliatum and A. omeiense are reported here for first time. B-chromosome were detected in A. paepalanthoides and A. plurifoliatum. The cytological and taxonomic relationships of the investigated species are discussed.