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 cot!on and of these blends were spun with a 3.75 T.M. into 38/1 (16 tex) filling yarns. \Vlth a common warp made from the same control cotton these filling yarns were woven into a 5-hames~, 3-eou~t, filling-faced sateen fabric' (37! in., 64 X 104, 4.37 ?z). The~rab and str~p 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~o the increase in short fiber content of the blend.Spectrophotometric analyses and visual examination of bleached and of bleachedand-dyed samples indicated th~practicality of these finishing operations on cottons containing as much as 10% of Dlplodia-damaged fiber.Field observations suggest that in commercial practice bales containing higher percentages of boll-;ot~amaged fiber th~n are represented by the 5% blend here employed are rare. .Data m~llls and the preced~ng c~mpanion paper indicate that within the range of processing techniques employed Dlplodla-damaged fiber exerts less detrimental effect than might have been anticipated.

No abstract

A limited quantity of specially selected seed cotton that had been damaged severely in the field by the common boll-rot fungus Diplodia sp. was roller-ginned and processed, along with a white control cotton, into blends containing 2.5%, 5.0%, 10.0%, and 35.0%. by weight, of the Diplodia-damaged lint. It was shown that the 35.0% blend could not be spun into a 38/1 (16 tex) yarn without an excessive number of ends down. The 10.0% blend could be utilized more efficiently in coarser-than-38/1 (16 tex) yarns. The 2.5% and 5.0% blends were spun into 38/1 (16 tex) yarns without an excessive number of ends down. The yarns from these two blends did not differ significantly from yarns spun from the control cotton in length uniformity, appearance grade, or yarn breaking tenacity and elongation. All cases of reduced processing efficiency and product quality in any of the blends, in comparison to the white control, were shown to be related to the short fiber content of the blends. Diplodia-damaged and undamaged bolls occur regularly together within a single cotton field, with a resulting admixture of the two kinds of fiber in the bale. Field observations suggest that in commercial bales amounts of fungus-damaged fiber in excess of that represented by the experimental 5% blend here employed are rare.