Zeven A C
Basic Life Sci. 1979;13:385-407. doi: 10.1007/978-1-4613-3069-1_20.
The origin and survival of a polyploid in a mixture of this polyploid and its parent(s) is reviewed. With several examples a picture is drawn of the interference of cytotypes in a mixture of cytotypes. Some natural polyploids, both wild and domesticated, are very successful. They, like bread wheat and banana, largely replaced their parents. The same is true for some artificial polyploids like autotriploid hybride sugar beet in Europe and autotetraploid perennial ryegrass. But when grown together with their parents for several generations they will disappear from this misture. Although in South America under primitive conditions, diploid, triploid, and tetraploid potatoes are grown, elsewhere only the tetraploids have survived. Various causes are presented to explain why the diploids and triploids succumbed. Autotetraploids of maize, rye, barley, and rice cannot maintain themselves in diploid/tetraploid mixtures. The maintenance of diploid or tetraploid rye varieties is less difficult as both are "self-cleaning" with respect to the other. Only two haploid cultivars exist but they can only maintain themselves with the help of man. It is concluded that the survival chances of a polyploid after its origination is low. Firstly, under conditions of random sampling a rare type has a very small chance of occurring in the next generation. Furthermore, seedset of triploids and tetraploids is often low which limits their survival. In addition, in mixtures of cross-fertilizing diploid and autotetraploids the n gamete has an advantage over the 2n gamete. This limits the survival of the autotetraploids again. It is concluded that our knowledge of the the mutual interference of cytotypes in a cytotype mixture is quite limited. Much more research is needed and some proposals concerning this research are made.
本文综述了多倍体在其与亲本的混合群体中的起源和存活情况。通过几个例子描绘了不同细胞型在细胞型混合群体中的相互干扰情况。一些天然多倍体，包括野生和驯化的，都非常成功。它们，如面包小麦和香蕉，在很大程度上取代了它们的亲本。欧洲的同源三倍体杂交甜菜和同源四倍体多年生黑麦草等一些人工多倍体也是如此。但当它们与亲本一起生长几代后，就会从这个混合群体中消失。虽然在南美洲的原始条件下，二倍体、三倍体和四倍体马铃薯都有种植，但在其他地方只有四倍体存活了下来。文中提出了各种原因来解释二倍体和三倍体为何会消亡。玉米、黑麦、大麦和水稻的同源四倍体无法在二倍体/四倍体混合群体中维持自身。二倍体或四倍体黑麦品种的维持相对不那么困难，因为两者对另一方都具有“自我净化”能力。目前仅存在两个单倍体品种，但它们只能在人类的帮助下维持自身。得出的结论是，多倍体起源后的存活机会很低。首先，在随机抽样的情况下，稀有类型在下一代中出现的机会非常小。此外，三倍体和四倍体的结实率通常较低，这限制了它们的存活。此外，在异花授粉的二倍体和同源四倍体的混合群体中，n配子比2n配子具有优势。这再次限制了同源四倍体的存活。得出的结论是，我们对细胞型混合群体中不同细胞型相互干扰的了解相当有限。需要进行更多的研究，并提出了一些关于这项研究的建议。
