|Johnson, R - TEXAS TECH UNIVERSITY|
Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: March 21, 1999
Publication Date: N/A
Technical Abstract: The high priority assigned by the post-harvest sector of the cotton industry to minimizing short fiber content [SFC] has accelerated addition of SFC measurement to classing office HVI systems. Documenting post harvest SFC at the bale level is expected to reduce the cost of textile processing and increase the value of the raw fiber. However, little is known about pre-harvest SFC. The SFC data discussed here were quantified using a single calibration standard and AFIS-A2. Fibers were separated from seeds by dissection, roller-ginning, or saw-ginning [with no lint cleaner]. Fourteen Upland genotypes from five crops in SC, MS or a LA greenhouse are represented. The SFC range found was 16.1% [saw-ginned DPL20] to 4.6% [greenhouse-grown, dissected DPL50]. Genotype, crop year, and boll position on the plant all had significant effects on SFC. Significant differences in SFC were found in two locules from the same boll. Elevated ozone levels decreased SFC. The rate of SFC decrease over time was altered by environmental factors that modified fiber maturation. Saw-ginned SFC ranged from 6.8% to 11.8% in a soil spatial variability study, and a weak negative correlation was found between SFC and soil phosphorus. Yield and SFC were positively correlated, but no significant relationships were found between SFC and fiber bundle strength or elongation. Correlations between SFC and yarn elongation and breaking strength were not consistent across genotypes or crop years. The few links found between SFC and pre-harvest environment and/or crop management were neither consistent nor strong enough to warrant inclusion of SFC among the fiber properties used to set the bale price paid to the producer, who cannot manage the crop to achieve a set SFC range.