Cotton Improvement — Genetic Progress in Economic Traits.

The modern era of cotton (Gossypium hirsutum and Gossypium barbadense) plant breeding started shortly after the rediscovery of Mendel’s laws of inheritance. Both public and private sector cotton plant breeders applied Mendelian genetics to the economic traits of fiber and seed, quality and yield and the agronomic traits of early maturity, disease resistance and storm resistance. Improvements were slow and arduous due to the polygenic inheritance of complex traits in a tetraploid and low level of investment in plant breeding in this self pollinated predominated farm saved seed crop. Progress was made in fungal and bacterial disease resistance and harvest index which allowed earliness and escape from severe injury associated with several pathogens and late season insect pests. Progress in fiber quality was related to National and regional objectives in satisfying specific fiber quality markets, typically longer fiber length for fine count ring spun yarns and higher strength cotton for high speed rotor spun yarns. The introduction of tools to protect the genetic intellectual property of improved cultivars such as plant breeder’s rights, hybrid seed, gene and variety patents, and application of contract law to seed purchases occurred concomitantly with the introduction of Biotechnology in cotton. This combination of enhanced intellectual property rights with the enhanced farmer value of planting seed containing Biotech traits spurred substantial investment in cotton plant breeding around the world leading to recent gains in fiber yield and quality. Progress in the economic traits has been rapid during the previous 15 years as many of the private plant breeding investments have come to fruition. In addition, cotton plant breeding has very recently employed some of the genetic innovations created for medical advancement, hybrid corn breeding and plant biology which should further stimulate progress in economic traits. Analysis and examples from various cotton producing countries will be used to illustrate this history.