孟德尔的论文

上传人:s9****2 文档编号:513202204 上传时间:2022-09-13 格式:DOC 页数:28 大小:224KB
返回 下载 相关 举报
孟德尔的论文_第1页
第1页 / 共28页
孟德尔的论文_第2页
第2页 / 共28页
孟德尔的论文_第3页
第3页 / 共28页
孟德尔的论文_第4页
第4页 / 共28页
孟德尔的论文_第5页
第5页 / 共28页
点击查看更多>>
资源描述

《孟德尔的论文》由会员分享,可在线阅读,更多相关《孟德尔的论文(28页珍藏版)》请在金锄头文库上搜索。

1、孟德尔的论文植物杂交试验(1865)资料来源:Experiments in Plant Hybridization (1865)by Gregor MendelIntroductory RemarksExperience of artificial fertilization, such as is effected with ornamental plants in order to obtain new variations in color, has led to the experiments which will here be discussed. The striking reg

2、ularity with which the same hybrid forms always reappeared whenever fertilization took place between the same species induced further experiments to be undertaken, the object of which was to follow up the developments of the hybrids in their progeny. To this object numerous careful observers, such a

3、s Klreuter, Grtner, Herbert, Lecoq, Wichura and others, have devoted a part of their lives with inexhaustible perseverance. Grtner especially in his work Die Bastarderzeugung im Pflanzenreiche The Production of Hybrids in the Vegetable Kingdom, has recorded very valuable observations; and quite rece

4、ntly Wichura published the results of some profound investigations into the hybrids of the Willow. That, so far, no generally applicable law governing the formation and development of hybrids has been successfully formulated can hardly be wondered at by anyone who is acquainted with the extent of th

5、e task, and can appreciate the difficulties with which experiments of this class have to contend. A final decision can only be arrived at when we shall have before us the results of detailed experiments made on plants belonging to the most diverse orders. Those who survey the work done in this depar

6、tment will arrive at the conviction that among all the numerous experiments made, not one has been carried out to such an extent and in such a way as to make it possible to determine the number of different forms under which the offspring of the hybrids appear, or to arrange these forms with certain

7、ty according to their separate generations, or definitely to ascertain their statistical relations. It requires indeed some courage to undertake a labor of such far-reaching extent; this appears, however, to be the only right way by which we can finally reach the solution of a question the importanc

8、e of which cannot be overestimated in connection with the history of the evolution of organic forms. The paper now presented records the results of such a detailed experiment. This experiment was practically confined to a small plant group, and is now, after eight years pursuit, concluded in all ess

9、entials. Whether the plan upon which the separate experiments were conducted and carried out was the best suited to attain the desired end is left to the friendly decision of the reader.Selection of the Experimental PlantsThe value and utility of any experiment are determined by the fitness of the m

10、aterial to the purpose for which it is used, and thus in the case before us it cannot be immaterial what plants are subjected to experiment and in what manner such experiment is conducted. The selection of the plant group which shall serve for experiments of this kind must be made with all possible

11、care if it be desired to avoid from the outset every risk of questionable results. The experimental plants must necessarily: 1. Possess constant differentiating characteristics. 2. The hybrids of such plants must, during the flowering period, be protected from the influence of all foreign pollen, or

12、 be easily capable of such protection.The hybrids and their offspring should suffer no marked disturbance in their fertility in the successive generations. Accidental impregnation by foreign pollen, if it occurred during the experiments and were not recognized, would lead to entirely erroneous concl

13、usions. Reduced fertility or entire sterility of certain forms, such as occurs in the offspring of many hybrids, would render the experiments very difficult or entirely frustrate them. In order to discover the relations in which the hybrid forms stand towards each other and also towards their progen

14、itors it appears to be necessary that all member of the series developed in each successive generations should be, without exception, subjected to observation. At the very outset special attention was devoted to the Leguminosae on account of their peculiar floral structure. Experiments which were ma

15、de with several members of this family led to the result that the genus Pisum was found to possess the necessary qualifications. Some thoroughly distinct forms of this genus possess characters which are constant, and easily and certainly recognizable, and when their hybrids are mutually crossed they

16、 yield perfectly fertile progeny. Furthermore, a disturbance through foreign pollen cannot easily occur, since the fertilizing organs are closely packed inside the keel and the anthers burst within the bud, so that the stigma becomes covered with pollen even before the flower opens. This circumstance is especially important. As additional advantages worth mentioning, there may be cited the easy culture of these plants in the open ground and in pots,

展开阅读全文
相关资源
正为您匹配相似的精品文档
相关搜索

最新文档


当前位置:首页 > 高等教育 > 研究生课件

电脑版 |金锄头文库版权所有
经营许可证:蜀ICP备13022795号 | 川公网安备 51140202000112号