PHYSIOLOGICAL GENOMICS OF COTTON FIBER DEVELOPMENT

¹ USDA ARS Cropping Systems Research Lab, 3810 4th Street, Lubbock, TX, 79415, USA

² USDA ARS Crop Genetics and Production Lab, Box 345, Stoneville, MS, 38776, USA

³ Dept. of Soil and Crop Sciences, Texas A&M University, College Station, TX, 77843, USA

⁴ Dept. of Biology, Texas Tech University, Lubbock, TX, 79409, USA

Cotton fiber yield and quality is affected by environmental, physiological, and developmental changes. We have formed a genomics consortium to study stress physiology and fiber development. The consortium has generated stress-induced, fiber-, stem-, ovule-, and boll-specific libraries that are potentially enriched in sequences not present in the public EST collection. To date, we have generated approximately 24,500 ESTs. Initial analysis of a subset of 2,229 unigenes from drought-stressed bolls, shows over 14% of a have no match in the databases and almost one-third of these sequences are not found in current cotton fiber EST collections. Our goals are to (1) develop cotton microarrays using ~10,000 unigene ESTs and cDNA sequences; (2) determine transcriptome changes of cotton plants under drought and cold stress; (3) determine genes and pathways involved in partitioning photoassimilate between agronomically irrelevent storage tissues and agronomically important reproductive tissues during fiber development, and (4) develop ESTs in immature ovules for mechanistic studies on fiber cell differentiation. Progress toward these goals and the development of a unigene set for array analysis will be reported at this meeting.