Genome Mapping &Molecular Breeding. Vol. 7: Technical Crops.
The most important renewable natural textile fiber worldwide and the worldıs sixth largest source of vegetable oil is cotton. After losing some ground to synthetic fibers in the past, the demand for cotton has been steadily growing. Between 1998 and 2003, there were five consecutive records for cotton consumption with a net gain of 2.6 million tons of cotton finding its way to textile mills (Valderrama 2004). The other side of this coin is the competitiveness of the supply market has also increased. Production is also increasing, as is yield per hectare, and the price of cotton relative to other textile fibers is declining (Valderrama 2004; Anonymous 2005). The cotton growers who survive through the next decade will be those who can produce the most cotton per unit input and produce cotton whose characteristics attract price premiums, and this is the message being delivered to cotton breeders around the world. While perennial concerns regarding pest and disease resistance and yield remain, water-use efficiency/drought tolerance, fiber quality and uniformity are high priorities for the future of cotton improvement. The challenge for the breeders is that all the high priority breeding objectives for the next decade are phenotypically complex traits controlled by many interacting genes. Making real breeding gains for these complex traits will require an unprecedented understanding of the molecular genetics of these traits. The purpose of this chapter is not to review the cotton plant and/or the cotton crop in whole which would involve the physiology of the plant and fiber, and/or production and marketing methods, but to provide enough information of the cotton crop in order for the reader to understand the more recent research events in cotton molecular DNA technology and the state of the art in genetic linkage mapping, one of the primary tools breeders will use to reach their breeding objectives in the next decade.