Gao Yan-Hui, Zhu Shui-Jin, Ji Dao-Fan
Agronomy Department, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029, China.
Yi Chuan Xue Bao. 2005 Jul;32(7):744-52.
Interspescific hybridization among four cultivated species in Gossypium (G. herbaceum, G. arboreum, G. hirsutum and G. barbadense) were carried out to produce dispecific hybrids F1, (G. arboreum x G. herbaceum) F1 and (G. hirsutum x G. barbadense) F1, and quadrispecific hybrid F1, which was produced by crossed the chromosome doubled (G. arboreum x G. herbaceum) F1 with (G. hirsutum x G. barbadense) F1. In order to study the evolution relationship among the four cultivated species in Gossypium, the characteristic of chromosome behavior during the meiosis and pollen viability in those interspecific hybrids F1 were studied in this paper. The results showed that the diploid interspecific hybrid, (G. arboreum x G. herbaceum) F1, had a four-chromosome-ring, the chromosome configuration was 2n = 26 = 11 II + 1 IV. And the normal pollen percent was 50.71%, which showed the character of typical gamete semi-sterility, and approved that there was a chromosome translocation between the two diploid cotton species, G. arboreum and G. herbaceum. For the allotetraploid species interspecific hybrid F1, (G. hirsutum x G. barbadense) F1, most of the chromosomes at metaphase I could be paired into bivalents, with a few number of univalents, trivalents, and quardrivalents. The chromosome configuration was 2n = 52 = 0.78 I +22.24 II +0.94 III +0.98 IV, with a normal pollen rate of 54. 84%. The experiment showed that there were a few chromosome translocation or chromosome inversion between the two allotetraploid cotton species, G. hirsutum and G. barbadenses. The meiosis of the quardrispecific hybrid F1 was abnormal, and the loss of chromosomes was common. Most of the chromosomes could not synapse at metaphase I, which led to many univalents and some multivalents. The chromosome configuration of the quardrispecific hybrid F1 was 2n = 52 = 5.45 I +14.41 II +2.44 III +1.59 IV +0.63 V +0.15 VI, and the normal pollen rate was 6.87%, which showed that the relationship of four cultivated cotton species was relatively closed. It is possible to produce a new germplasm with the good characters of the four cultivated species through genetic recombination.
对棉属四个栽培种（草棉、亚洲棉、陆地棉和海岛棉）进行种间杂交，以获得双二倍体杂种F1（亚洲棉×草棉）F1和（陆地棉×海岛棉）F1，以及通过将染色体加倍的（亚洲棉×草棉）F1与（陆地棉×海岛棉）F1杂交产生的四倍体杂种F1。为了研究棉属四个栽培种之间的进化关系，本文研究了这些种间杂种F1减数分裂过程中染色体行为特征和花粉活力。结果表明，二倍体种间杂种（亚洲棉×草棉）F1形成了一个四染色体环，染色体构型为2n = 26 = 11II + 1IV。正常花粉百分率为50.71%，表现出典型的配子半不育特征，证实亚洲棉和草棉这两个二倍体棉种之间存在染色体易位。对于异源四倍体种间杂种（陆地棉×海岛棉）F1，中期I的大多数染色体可配对形成二价体，有少量单价体、三价体和四价体。染色体构型为2n = 52 = 0.78I + 22.24II + 0.94III + 0.98IV，正常花粉率为54.84%。实验表明，陆地棉和海岛棉这两个异源四倍体棉种之间存在少量染色体易位或染色体倒位。四倍体杂种F1的减数分裂异常，染色体丢失常见。中期I时大多数染色体不能联会，导致许多单价体和一些多价体。四倍体杂种F1的染色体构型为2n = 52 = 5.45I + 14.41II + 2.44III + 1.59IV + 0.63V + 0.15VI，正常花粉率为6.87%，表明四个栽培棉种之间的关系相对紧密。通过基因重组有可能培育出具有四个栽培种优良性状的新种质。
