Wild cotton species are an important source of desirable genes for genetic improvement of cultivated cotton Gossypium hirsutum Linnaeus, 1763. For the success of such an improvement, chromosome pairings and recombinations in hybrids are fundamental. The wild African species G. longicalyx Hutchinson & Lee, 1958 could be used as donor of the desirable trait of fiber fineness. Twelve BC1 plants obtained from the backcrossing of [(G. hirsutum × G. thurberi Todaro, 1877)2 × G. longicalyx] (AhDhD1F1, 2n = 4x = 52) trispecies hybrid (HTL) by G. hirsutum (cv. C2) (AhAhDhDh, 2n = 4x = 52) were investigated for meiotic behaviour and plant fertility. Their chromosome associations varied as follows: (2.5 to 11.5) I + (17 to 22) II + (0.31 to 1.93) III + (0.09 to 1.93) IV + (0 to 0.07) V + (0 to 0.14) VI. Their pollen fertility ranged from 4.67 to 32.10 %. Only four BC1 plants produced a few seeds through self-pollination. The remaining BC1 were totally self-sterile and usually presented the highest number of univalents. All BC1 materials produced BC2 seeds (0.44 to 6.50 seeds per backcross) with the number of seeds negatively correlated with the number of univalents (R2 = 0.45, P < 0.05). Most BC1 plants gave significantly finer fiber compared to the cultivated G. hirsutum. SSR markers showed a segregation of wild alleles among the backcross derivatives and Genomic in situ hybridization (GISH) revealed presence of entire chromosomes of G. longicalyx as well as recombinant chromosomes in the backcross derivatives. The significance and details of these results are presented and the prospects of successfully exploiting these plant materials are discussed.

中文翻译：

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[（Gossypium hirsutum×G. thurberi）2×G. longicalyx]三物种杂种的回交1衍生物的减数分裂行为与育性之间的关系。

野生棉种是栽培棉棉花的遗传改良所需基因的重要来源，1763年。为使这种改良成功，杂交中的染色体配对和重组至关重要。非洲野生种G. longicalyx Hutchinson和Lee，1958年可以用作纤维细度理想特性的捐助者。十二个BC1植物是从[（G. hirsutum×G. thurberi Todaro，1877）2×G. longicalyx]（AhDhD1F1，2n = 4x = 52）三物种杂种（HTL）与G. hirsutum（cv。C2）杂交获得的。 （AhAhDhDh，2n = 4x = 52）研究了减数分裂行为和植物育性。它们的染色体关联变化如下：（2.5至11.5）I +（17至22）II +（0.31至1.93）III +（0.09至1.93）IV +（0至0.07）V +（0至0.14）VI。它们的花粉育性为4.67％至32.10％。只有四株BC1植物通过自花授粉产生了一些种子。其余的BC1完全是自我无菌的，通常呈现最高的单价数。所有BC1材料产生的BC2种子（每个回交的种子为0.44至6.50种子），且种子数量与单价数量呈负相关（R2 = 0.45，P <0.05）。与栽培的G. hirsutum相比，大多数BC1植物的纤维细得多。SSR标记显示回交衍生物之间野生等位基因的隔离，而基因组原位杂交（GISH）显示了G. longicalyx的整个染色体以及回交衍生物中的重组染色体。介绍了这些结果的意义和细节，并讨论了成功开发这些植物材料的前景。