The CIRAD cotton collection contains more than half species of the genus Gossypium, and is one of the 6 major centers for the worldwide protection of biodiversity in this genus.
Urbanization and the extension of agricultural land are currently causing an intense loss of genetic diversity in tropical regions, and specialists consider that ex-situ conservation (collections outside the species' natural regions) is the only solution in the case of certain plants such as cotton plants.
Currently, only the 999 accessions resulting from natural environment surveys are available on the Florilège portal. To access cultivated accessions, please consult the CRB portal : Catalogue Coton du CRB-Gamét (cirad.fr)
CIRAD's cotton germplasm collection was created in 1978 by bringing together several collections. It is one of the world's largest collections, representing the genetic variability of the Gossypium L. genus.
In 2005, it contained 3070 accessions, including 1696 cultivars and 1374 wild ancestral types, incorporating five tetraploid and seven diploid species. The two main cultivated cotton species, G. hirsutum L. and G. barbadense L., account for 68% and 15% of accessions respectively.
The cultivars come from around a hundred countries, and accessions of ancestral species were collected during expeditions between 1980 and 1988. Part of the ancestral type collection (894 accessions) was assembled with funding from IBPGR (now Biodiversity International), and these accessions were handed over to CIRAD for conservation, evaluation and distribution.
The cotton collection is used for a variety of purposes, depending on the user.
Conservation of the genetic diversity of the genus Gossypium :
CIRAD's cotton genebank contains more than half of the species in the Gossypium genus, and is one of the 6 major centers for the protection of biodiversity in this genus worldwide.
Genetic resources for varietal improvement :
In CIRAD's cotton genebank, cultivated species are represented by hundreds of genotypes, cultivated varieties and more or less wild types, constituting a reservoir of genetic diversity that can be directly mobilized for genetic improvement programs.
Identification of useful genes and the functioning of tetraploid genomes
The germplasm in CIRAD's gene bank is used to search for usable genes (QTLs and candidate genes), either by using current data on phenotypic characterization of the material, or by conducting experiments to acquire data on special characters (resistance to drought, diseases and pests); cotton plants are partly tetraploid species, partly diploid, whose comparative study has led to a better understanding of polyploid genomes (a large number of cultivated species are polyploid).
Scientific research activities involving the CIRAD Cotton Gene Bank :
- Association genetics for drought adaptation on a panel of 200 G. hirsutum varieties;
- Identification of new sources of resistance to root-knot nematode in Cirad + Embrapa collections
- Coupled phylogeographic-genetic study of wild cotton plants in Mesoamerica
- Microsatellite diversity within the G. barbadense species (in collaboration with Peru)
- Varietal selection program in Cameroon in collaboration with SODECOTON and IRAD.