棉属多倍化研究进展

多倍化在许多植物的物种形成及其随后的进化过程中发挥了关键作用。棉花是一个大属，一些棉种的起源发生过多倍体化，部分二倍体种是染色体二倍化的多倍体，比克氏棉最典型，拟似棉最复杂，还有D基因组的旱地棉和B基因组的3个种。陆地棉等5个异源四倍体种是多倍体化典型，是由A与D基因组近似的祖先种经过杂交和染色体加倍的双二倍体。它们的D亚组供体亲本种，前人认同的是雷蒙德氏棉，然而近期荧光原位杂交和叶绿体基因组学研究，提出了雷蒙德氏棉可能不是陆地棉亲本种的观点。四倍体棉种形成的多倍体化过程有多种推论，较为共识的时期是中更新世，结合近期包括叶绿体在内的基因组学的研究支持中更新世或更后些时候。荧光原位杂交、包括叶绿体在内的基因组学将为棉花多倍化分析提供更多的证据。

Study Progress of Gossypium Polyploidization

Polypoidization plays a key role in plant speciations and their evolution, the genus Gossypium, as a good example. Gossypum is a big genus in crops. There might exist polyploidy processes in most cotton species and many diploid cotton specie are a kind of polyploid which kept diploid chromosomes but existed polploidization. Gossypium bickii is a typical one and G. gossypioides is very special in the genus. The polyploidy indued species include G. aridum and three ones of B genome. In Gossypium allotetraploid speies is a typically polyploid origination. G. raimondii was generally considered as the closest donor of allotraploid cotton D-subgenome s but was not taken so at least to the G. hirsutum D-subgenome verified with gDNA-FISH. The allotraploid cotton sepeciation took place perhaps in Mid-Pleistocene or a little later. Recent FISH studies on cotton contributed much to speciations, interspecific relationships, and evolutions in Gossypium. There will be great advantages of FISH and genomics including cp-genome in studies on cotton polyploidization.