The Utilization of Diplodia -Damaged Boll-Rot Cotton

Cotton fiber severely damaged by the boll-rot fungus Diplodia sp. was blended with a control white cotton in percentages of 2.5, 5.0, 10.0, and 35.0. Equal amounts of the control cotton and of these blends were spun with a 3.75 T.M. into 38/1 (16 tex) filling yarns. With a common warp made from the same control cotton, these filling yarns were woven into a 5-harness, 3-count, filling-faced sateen fabric (37½ in., 64×104, 4.37 oz). The grab and strip breaking strengths and resistance to tearing and flex abrasion of fabrics whose filling yarns contained up to 5% of Diplodia fiber were not appreciably lower than those of the fabric having the control cotton in the filling. The large drop in value of these fabric properties when the 35% Diplodia-fiber filling was used was attributed to the increase in short fiber content of the blend.

Spectrophotometric analyses and visual examination of bleached and of bleached-and-dyed samples indicated the practicality of these finishing operations on cottons containing as much as 10% of Diplodia-damaged fiber.

Field observations suggest that in commercial practice bales containing higher percentages of boll-rot damaged fiber than are represented by the 5% blend here employed are rare. Data in this and the preceding companion paper indicate that within the range of processing techniques employed Diplodia-damaged fiber exerts less detrimental effect than might have been anticipated.