Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: 1/12/2008
Publication Date: 2/21/2008
Citation: Turley, R.B. 2008. Genetics of Cotton Fiber Initiation: Inheritance Studies on Three Fiberless Lines. National Cotton Council Beltwide Cotton Conference.http://ncc.confex.com/ncc/2008/techprogram/MEETING/htm Interpretive Summary:
Technical Abstract: Fiber initiation, or the protuberate expansion of individual cells in the epidermis of cotton ovules, is a key component of lint percentage. Ovular trichomes are classified as either lint or fuzz based on the timing of fiber initiation. Initiation of lint fiber begins at anthesis and continues for about two days, whereas, the much shorter fuzz fiber initiates approximately a week later (Stewart 1975). The initiation of most fuzz and some lint fiber is arrested by the fuzzless seed alleles N1 and n2. The fiberless phenotype of four cotton lines have been associated with the expression of the fuzzless seed loci, such as MD17 (N1N1n2n2; Turley and Kloth 2002), XZ142w (n2n2li3li3; Zhang and Pan 1991), SL1-7-1 (N1N1fl1fl1n3n3: Turley and Kloth submitted) and L40 (Ft1Ft1Ft2Ft2FtcFtcN1N1; Musaev and Abzalov 1972). Presently, the only fiberless line reported without fuzzless seed progeny in either the F1 or F2 populations of crosses with wildtype cotton is MCU5 fiberless (2 to 4 undetermined loci; Nandarajan and Rangasamy 1988; Peter et al 1984). With these genotypes, three new loci were proposed which interact with the expression of a fuzzless seed locus, n2, to form either a fuzzless or a fiberless seed phenotype. The n3 locus interacts with the n2 locus to produce a fuzzless seed (Turley and Kloth 2002), the li3li3 (Zhang and Pan 1991) and fl1fl1 (Turley and Kloth unpublished) loci interact with the n2 locus to form fiberless seeds. No additional phenotypes have been reported for n3, li3 and fl1. Because these loci interact to control fiber initiation, it is imperative to identify and characterize each locus and the type of interaction.