Contributions possibles des innovations génétiques pour l'améloration de la compétitivité des filières cotonnières africaines

Possible contributions of genetic innovations to improvement in the competitivity of the cotton production and marketingchains in Africa. The 3 components of the profi tability of the cotton production and marketing chains which can beimproved following the development of genetic innovations concern: (i) the production cost of the cottonseed, thanks tothe introduction in the cultivated varieties of genes allowing to decrease the impact of the biotic (weeds, pests and diseases)and abiotic (drought, soil poverty, acidity and salinity) constraints, (ii) the cost of the ginning of the cottonseed and (iii) thequality of the various products of the cotton plant (fi ber, cakes, oil). The priorities to be retained for Africa regarding these3 components must absolutely take into account the characteristics of the local farming systems. In Africa, most of cottonis produced in farms of relatively small size with a low level of mechanization of the farming operations and a recourseto quantities of manure and pesticides defi nitely lower than elsewhere in the world whereas the levels of biotic and abioticconstraints are at least as high there as in the other continents. In this context, the priority of the genetic improvement programsshould aim at developing varieties with high quality fi ber, multi-resistant to the biotic and abiotic adversities, with the highestpossible ginning outturn and presenting an inhibition of the synthesis of the gossypol only at seed level. According to the localpriorities and resources available, the development of the new varieties should ideally be done by combining the approachesof the traditional genetic improvement assisted by the use of DNA markers and the functional genomics tools to direct theimplementation of targeted genetic transformations. This will not be possible without the maintenance of strong structures ofgenetic improvement directly in contact with the fi eld realities specifi c to each great zone of production. The exploitation of theimmense reserve of variability constituted by the wild diploid cotton species should play a key role to achieve these goals.