Cotton Breeding for Fiber Quality Improvement - Industrial Crops: Breeding for BioEnergy and Bioproducts - page 189

Chapter 10
Cotton Breeding for Fiber Quality
Improvement
Greg Constable, Danny Llewellyn, Sally Ann Walford,
and Jenny D. Clement
Abstract Cotton ( Gossypium hirsutum L.) is the world's leading fiber crop, grown
or processed in many countries, providing a major contribution to their economies.
Yield is economically most important to a producer which drives cultivar develop-
ment and adoption; however, fiber quality is the primary focus for spinning mills.
Cotton fiber quality must improve to remain competitive with synthetics due to
increased demands for lightweight casual garments which require longer, stronger,
and finer fibers. Improved cotton yields and fiber quality have continued to be
realized through science-based plant breeding, particularly in countries and pro-
duction systems with suitable climate and appropriate management inputs to
maximize those improvements. The most significant challenge for cotton breeders
has been to combine high yield with improved fiber quality, due to negative
associations between yield and quality attributes in G. hirsutum . This chapter
highlights practices to enable simultaneous improvement of yield and fiber quality
during conventional breeding. There are adequate genetic resources available for
innovative cotton breeders to make more progress, but new tools being offered by
modern molecular technologies will achieve those gains more efficiently. Advances
in fiber quality science have been made in cotton biotechnology - by improving our
understanding of fiber development phases that contribute to fiber quality through
gene discovery, genome mapping, and identification of linked molecular markers.
Novel biotechnology traits have the potential to improve fiber yield and quality by
altering the developmental phase associated with fibers per seed, fiber length,
strength, and fineness. Biotechnology tools to facilitate improved conventional
breeding through marker-assisted selection are also under development, particu-
larly high-throughput techniques based on single nucleotide polymorphisms
derived from next-generation sequencing. There are clearly great opportunities
for better integration of conventional breeding and molecular biology, and as new
GM traits are developed, a future challenge will be to combine multiple GM traits
into elite cultivars. This could be assisted by the judicious use of molecular markers
to herald a new age in cotton improvement. Cotton is one of the pioneer crops for