Leal-Bertioli Soraya C M, Santos Silvio P, Dantas Karinne M, Inglis Peter W, Nielen Stephan, Araujo Ana C G, Silva Joseane P, Cavalcante Uiara, Guimarães Patricia M, Brasileiro Ana Cristina M, Carrasquilla-Garcia Noelia, Penmetsa R Varma, Cook Douglas, Moretzsohn Márcio C, Bertioli David J
Embrapa Genetic Resources and Biotechnology, PqEB W5 Norte Final, CP 02372, CEP 70.770-917, Brasília, DF, Brazil, University of Brasilia, Institute of Biological Sciences, Campus Darcy Ribeiro, CEP 70.910-900, Brasília, DF, Brazil, Catholic University of Brasilia, Biotechnology and Genomic Sciences, SGAN 916 Avenida W5, CEP 70.790-160, Brasilia, DF, Brazil, Plant Breeding and Genetics Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna International Centre, Vienna A-1400, Austria and Department of Plant Pathology, University of California at Davis, One Shields Avenue, Davis, CA 95616, USA
Embrapa Genetic Resources and Biotechnology, PqEB W5 Norte Final, CP 02372, CEP 70.770-917, Brasília, DF, Brazil, University of Brasilia, Institute of Biological Sciences, Campus Darcy Ribeiro, CEP 70.910-900, Brasília, DF, Brazil, Catholic University of Brasilia, Biotechnology and Genomic Sciences, SGAN 916 Avenida W5, CEP 70.790-160, Brasilia, DF, Brazil, Plant Breeding and Genetics Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna International Centre, Vienna A-1400, Austria and Department of Plant Pathology, University of California at Davis, One Shields Avenue, Davis, CA 95616, USA Embrapa Genetic Resources and Biotechnology, PqEB W5 Norte Final, CP 02372, CEP 70.770-917, Brasília, DF, Brazil, University of Brasilia, Institute of Biological Sciences, Campus Darcy Ribeiro, CEP 70.910-900, Brasília, DF, Brazil, Catholic University of Brasilia, Biotechnology and Genomic Sciences, SGAN 916 Avenida W5, CEP 70.790-160, Brasilia, DF, Brazil, Plant Breeding and Genetics Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna International Centre, Vienna A-1400, Austria and Department of Plant Pathology, University of California at Davis, One Shields Avenue, Davis, CA 95616, USA.
Ann Bot. 2015 Feb;115(2):237-49. doi: 10.1093/aob/mcu237. Epub 2014 Dec 22.
Arachis batizocoi is a wild relative of cultivated peanut (A. hypogaea), an allotetraploid with an AABB genome. Arachis batizocoi was once considered the ancestral donor of the peanut B genome, but cytogenetics and DNA phylogenies have indicated a new genome classification, 'K'. These observations seem inconsistent with genetic studies and breeding that have shown that A. batizocoi can behave as a B genome.
The genetic behaviour, genome composition and phylogenetic position of A. batizocoi were studied using controlled hybridizations, induced tetraploidy, whole-genome in situ fluorescent hybridization (GISH) and molecular phylogenetics.
Sterile diploid hybrids containing AK genomes were obtained using A. batizocoi and the A genome species A. duranensis, A. stenosperma, A. correntina or A. villosa. From these, three types of AAKK allotetraploids were obtained, each in multiple independent polyploidy events. Induced allotetraploids were vigorous and fertile, and were hybridized to A. hypogaea to produce F1 hybrids. Even with the same parental combination, fertility of these F1 hybrids varied greatly, suggesting the influence of stochastic genetic or epigenetic events. Interestingly, hybrids with A. hypogaea ssp. hypogaea were significantly more fertile than those with the subspecies fastigiata. GISH in cultivated × induced allotetraploids hybrids (harbouring AABK genomes) and a molecular phylogeny using 16 intron sequences showed that the K genome is distinct, but more closely related to the B than to the A genome.
The K genome of A. batizocoi is more related to B than to the A genome, but is distinct. As such, when incorporated in an induced allotetraploid (AAKK) it can behave as a B genome in crosses with peanut. However, the fertility of hybrids and their progeny depends upon the compatibility of the A genome interactions. The genetic distinctness of A. batizocoi makes it an important source of allelic diversity in itself, especially in crosses involving A. hypogaea ssp. hypogaea.
巴蒂佐花生（Arachis batizocoi）是栽培花生（A. hypogaea）的野生近缘种，是一种具有AABB基因组的异源四倍体。巴蒂佐花生曾被认为是花生B基因组的祖先供体，但细胞遗传学和DNA系统发育研究表明其基因组有新的分类，即“K”基因组。这些观察结果似乎与遗传学研究和育种结果不一致，遗传学研究和育种表明巴蒂佐花生可表现出B基因组的特性。
利用可控杂交、诱导四倍体、全基因组原位荧光杂交（GISH）和分子系统发育学研究了巴蒂佐花生的遗传行为、基因组组成和系统发育位置。
利用巴蒂佐花生与A基因组物种杜兰花生（A. duranensis）、窄叶花生（A. stenosperma）、科连蒂纳花生（A. correntina）或绒毛花生（A. villosa）获得了含有AK基因组的不育二倍体杂种。从中获得了三种类型的AAKK异源四倍体，每种类型都经历了多次独立的多倍体化事件。诱导产生的异源四倍体生长旺盛且可育，并与栽培花生杂交产生F1杂种。即使亲本组合相同，这些F1杂种的育性也有很大差异，这表明存在随机遗传或表观遗传事件的影响。有趣的是，与栽培花生亚种hypogaea的杂种比与亚种fastigiata的杂种育性显著更高。在栽培种×诱导异源四倍体杂种（含有AABK基因组）中进行的GISH以及利用16个内含子序列进行的分子系统发育研究表明，K基因组是独特的，但与B基因组的关系比与A基因组的关系更密切。
巴蒂佐花生的K基因组与B基因组的关系比与A基因组的关系更密切，但又有所不同。因此，当它被整合到诱导异源四倍体（AAKK）中时，在与花生杂交时可表现出B基因组的特性。然而，杂种及其后代的育性取决于A基因组相互作用的兼容性。巴蒂佐花生的遗传独特性使其本身成为等位基因多样性的重要来源，尤其是在涉及栽培花生亚种hypogaea的杂交中。
