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11.
芍药属的研究(1)——国产几个野生种核型的报道 总被引:1,自引:0,他引:1
In the present paper 8 species with 15 populations of the genus Paeonia L. (if P.
papaveracea and P. japonica are recognised as species) were collected from Sichuan, Shaanxi
and Hebei provinces (see the Appendix for detail of the materials). The micrographs of their
somatic metaphase (also Mii in the case of P.veitchii) are shown in Plates 1-4, the karyo-
type formulae, ranges of chromosome length and classification of karyotypes according to Steb-
bins (1971) are shown in Table 5: the idiograms in Figs. 1-2, and the parameters of chromo-
somes in Table 1-4. The essential points are mentioned as follows:
(1) Chromosomes of the various species in the section Modan have so far been examined
and they are all diploid, the two species in the section Onaepia are also diploid, and thus
tetraploids exist only in the section Paeonia.
(2) Chromosomes in the genus Paeonia are relatively stable except for the differentiation
of ploidy. The karyotypes (Table 1-4) show no differences among different taxa in Sect.
Modan and the same can also be said about the taxa in Sect. Paeonia (Table 1). Not only
are the karyotypes very similar, but also among the members within either section have the
same parameters of chromosomes, and, differences, if occur, are not statistically significant.
Between the two sections, however, the situation is different. The arm ratios of the first pairs of
chromosomes in Sect. Modan are 1.53, 1.52 and 1.48 (Table 1), but those in Sect. Paeonia
are 1.12-1.28 (Table 2-4), 95% confidence limits are 1.46-1.60 for the section Modan and
1.07-1.28 (1.21-1.35 only for PB85078) for the section Paeonia, not overlapping, which indi-
cates that the two sections have differentiated in respect of the first pairs of chromosomes.
(3)The population PB85024, which belongs to the P. obovata complex, has a karyotype of
2B (stebbins, 1971), which is a new one in the genus Paeonia. This karyotype is a stable one,
for several individuals in the population are uniform in this respect, which shows that Steb-
bins’ (1971) generalization that all the species in Paeonia have 2A does not hold true.
(4) Three populations of P. obovata complex studied in this work from Sichuan and
Shaanxi are all tetraploids, and one from Hebei is a diploid. From the present work and
the previcus reports, the materials from Japan and Korea, no matter whether flowers are pink
or white, are diploids, those from Heilongjiang Province (with both pink and white flowers)
(Liu Ming-yuan, personal communication) and from Heibei Province (with pink flowers)
in China are also diploids, the one from Sakhalin (pink flowers) is tetraploid, those from
Priamur of the Soviet Union are a tetraploid (with white flowers) and a diploid (with pink
flowers), and those from Shaanxi (the Qinling Range) and western Sichuan (with both pink
and white flowers) are all tetraploids. As far as we have now known, ploidy in this parti-
cular complex is correlated with the geographical distribution: diploids are found in the cen-
tral part, tetraploids occur in the northern limits, and in the south letraploids are the only
cytotype.
(5) The materials of P. mairei from western Sichuan and Shaanxi (the Qinling Range)
are found all to be tetraploids, which shows that two cytotypes, diploid and tetraploid, exist in
this species, but the geographical distribution pattern of these two cytotypes is to be revealed
in the future investigation. 相似文献
12.
高等院校的本科毕业设计是提高学生综合素质与创新能力的关键一环,也是高校教学中的一项重要内容,本文分析了目前高校毕业设计的现状与存在的问题,从多方面提出了保障毕业设计质量的工作措施。 相似文献
13.
14.
’95金秋,丹桂飘香,金风送爽,在由安徽省政府、文化部和中央电视台主办,安庆市政府、安徽省文化厅和旅游局承办的中国安庆第二届黄梅戏艺术节上,欢快的锣鼓点,悠扬的黄梅调,将长江北岸的重镇安庆装点得分外喜庆。11天中,来自湖北、江苏、安徽的黄梅戏演出,犹如一朵朵带露的山茶花,竞相怒放,又一次向人们集中展示了黄梅戏艺术的青春惑力,也带给人们以黄梅戏艺术在和时代的结合中变革发展的美好退思。从名篇名著中汲取丰厚的艺术营养和创作灵感,是这次艺术节上演剧目的一个突出特点。或许,这也是黄梅戏艺术发展的重要因素。由安… 相似文献
15.
新入园幼儿哭泣的原因 总被引:1,自引:0,他引:1
对于大多数幼儿教师和家长来说,面对新幼儿入园恐怕是最头疼的事情了,幼儿从自己温暖舒适,随心所欲的小家,来到有组织、有秩序的幼儿园这个大家庭里,刚开始是很难适应的,大多数幼儿总是以哭来表示他们的不满和反抗。 相似文献
16.
17.
山东省特殊教育中等专业学校是一所以盲、聋和肢残的残疾人为招生对象,培养计算机、财会、服装、按摩、工艺美术等专业人才的中等专业学校。学校建校时间较短,图书资料基础较差。随着现代信息技术的发展,学生的文献信息需求越来越大,对图书资料服务的要求越来越高。从学校的实际出发,立足当前,着眼发展,科学规划,精心组织,全面加强学校的文献信息建设和服务,更好地为教学服务,为培养高素质的残疾 相似文献
18.
在运动训练中,教练员常向运动员发出各种各样的运动强度的指令,对待这些强度指令,运动员是如何执行的?其反馈结果又如何?值得我们从理论上进一步探讨和研究。本文旨在运用运动生物力学和运动生理学的研究手法,通过观察和分析在不同的语言强度指令下地面支撑反作用力(GRF),跳跃高度(H)以及表面肌电图的积分(IEMG)等变化,对受试者在接受了口头相对强度指令后,完成运动强度指令时所产生的误差和腿部肌肉本体感觉器的反馈状况(FIELDBACK)进行分析,并运用肌肉调节过程中反馈机制的原理,探讨纵跳时肌肉运动调节能力(GRADING)的产生机制。为进一步充实和完善运动训练理论提供一些运动生物力学和运动生理学方面的参考数据。 相似文献
19.
20.