安徽山黧豆的核型

山黧豆属(又名香豌豆属)(Lathyrus Linn.)全世界共约140种,已做过染色体计数者72种。我国约16种,大部分产西南、西北和东北各省区。近年来皖南农学院朱玉简等同志在安徽宣城发现一新种,命名为安徽山黧豆(Lathyrus anhuiensis Y.J.Zhu et R.X.Meng)。鉴于该新种分布区非常局限,个体数也不多,为了及时掌握其细胞学情况,特通过该院叶如欣同志取得部分种子进行了染色体的计数和核型的描述。

KARYOTYPE OF LATHYRUS ANHUIENSIS

Lathyrus anhuiensis Y. J..Zhu et R. X. Meng, a new perennial species recently found in Anhui Province of southeastern China, has a very restricted distribution and limited in number of individuals. A cytological investigation was carried out promptly in order to reveal the karyotypical characteristics of the plant. The number of chromosomes in root-tip cell of the species was found to be 14, agreeing with most of the species of the same genus heretofore reported. In the light of chromosomal terminology defined by Levan and al.6], theka-ryotype formula is K (2n) = 14 = 4m + 2m (SAT) +8sm. Photomicrographs of the chromosome complement and the idiogram are shown in Figs. 1-2. Measurements in microns of the chromosome sets are given in Table 1. The karyotype of Lathyrus anhuiensis, which comprises chromosomes with either metacentric or submetacentric constrictions, is shown to be a symmetrical one, and belongs to Stebbins1 type "2A" of karyotypic asymmetry. This is in accord with the fact that symmetrical karyotypes are only found in the perennial instead of annual species of Lathyrus.7]