Possible contributions of genetic innovations to improvement in the competitivity of the cotton production and marketing chains in Africa.

摘要

The three components of the profitability of cotton production and marketing chains that can be improved following the development of genetic innovations concern: (i) the production cost of cottonseed, thanks to the introduction in the cultivated varieties of genes allowing to decrease the impact of biotic (weeds, pests and diseases) and abiotic (drought, poor soils, acidity and salinity) constraints; (ii) the cost of the ginning of the cottonseed; and (iii) the quality of the various products of the cotton plant (fibre, cakes, and oil). The priorities to be retained for Africa regarding these three components must absolutely take into account the characteristics of the local farming systems. In Africa, cotton is mostly produced in farms of relatively small size with a low level of mechanization and with low levels of manure and pesticide inputs than elsewhere in the world whereas the levels of biotic and abiotic constraints are at least as high as in the other continents. In this context, genetic improvement programmes should aim at developing varieties with high quality fibre, multi-resistant to the biotic and abiotic adversities, with the highest possible ginning outturn and presenting an inhibition of the synthesis of gossypol only at seed level. According to the local priorities and resources available, the development of new varieties should ideally be done by combining the approaches of traditional genetic improvement assisted by the use of DNA markers and functional genomics tools. This will not be possible without the maintenance of strong structures of genetic improvement directly in contact with the field realities specific to each major zone of production. The exploitation of the immense reserve of variability constituted by the wild diploid cotton species should play a key role to achieve these goals..