Molecular investigation of the genetic base of sugarcane cultivars

Molecular diversity was analysed among 162 clones of sugarcane using DNA restriction fragment length polymorphism (RFLP). One hundred and nine of them were modern cultivars of interspecific origin; most of them were bred in Barbados or in Mauritius. Fifty three were from #Saccharum officinarum# species, which is the major source of genes in modern cultivars, prevailing over the part of the genome incorporated from the wild species #Saccharum spontaneum#. Twelve low-copy nuclear DNA probes scattered over the genome were used in combination with one or two restriction enzymes. A total of 399 fragments was identified, 386 of which were polymorphic. Each sugarcane clone displayed a high number of fragments per probe/enzyme combination, illustrating the polyploid constitution of the genome. Among the #S. officinarum# clones, those from New Guinea had the largest variability and encompassed that present among clones collected from the Indonesian Islands and those known to have been involved in the parentage of modern cultivars. This is in agreement with the hypothesis that New Guinea is the centre of origin of this species. The clones from New Caledonia formed a separate group and could correspond to #S. officinarum# clones modified through introgression with other members of the '#Saccharum# complex'. Despite the low number of #S. officinarum# clones used for breeding cultivars, more than 80% of the markers present in the whole #S. officinarum# sample were also found in modern cultivars due probably to a high heterozygosity related to polyploidy. Among the cultivars, the two main groups, originating from Barbados and Mauritius, were clearly separated. This appeared essentially due to #S. spontaneum# alleles present in Mauritian cultivars and absent in Barbadan ones, probably in relation to the regular use of early generation interspecific hybrids in the breeding program employed in Mauritius. (Author's abstract)

Bibliographic Details

Main Authors:	Jannoo, Nazeema, Grivet, Laurent, Seguin, Marc, Paulet, Florence, Domaingue, Robert, Rao, P.S., Dookun, A., D'Hont, Angélique, Glaszmann, Jean-Christophe
Format:	article biblioteca
Language:	eng
Subjects:	F30 - Génétique et amélioration des plantes, Saccharum, Saccharum officinarum, Saccharum spontaneum, variation génétique, RFLP, polyploïdie, phylogénie, http://aims.fao.org/aos/agrovoc/c_6725, http://aims.fao.org/aos/agrovoc/c_6727, http://aims.fao.org/aos/agrovoc/c_6729, http://aims.fao.org/aos/agrovoc/c_15975, http://aims.fao.org/aos/agrovoc/c_34255, http://aims.fao.org/aos/agrovoc/c_6094, http://aims.fao.org/aos/agrovoc/c_13325,
Online Access:	http://agritrop.cirad.fr/391950/ http://agritrop.cirad.fr/391950/1/391950.pdf
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