It was the goal of the authors to create a set of reference cottons for maturity measurements. To achieve this they selected 104 cotton bales representing the two principal cultivated species. The vast majority of the bales originated in the USA, but some foreign-grown cotton bales were also selected (Egypt, Uzbekistan, Pakistan, Cameroon, Syria, Benin, and Australia). A representative sample of approximately 30 kg (70 pounds) was taken from each bale. Each sample was homogenized according to the protocol used by the International Cotton Calibration Standard Committee (ICCSC) to produce reference cottons. Eight sub-samples per bale were taken and a minimum of 500 cross-sections per sub-sample were analyzed. A broad range of average values of fiber perimeter and fiber maturity for the 104 bales were obtained. Evaluation of the mathematical and statistical relationships pertinent to maturity and fineness revealed that four critical criteria for adequate calibration standards were met. Therefore, this population of bales constitutes a good base for the calibration of the indirect measurement instruments for maturity and fineness.

Prior data indicated that enhanced availability of sucrose, a major product of photosynthesis in source leaves and the carbon source for secondary wall cellulose synthesis in fiber sinks, might improve fiber quality under abiotic stress conditions. To test this hypothesis, a family of transgenic cotton plants (Gossypium hirsutum cv. Coker 312 elite) was produced that over-expressed spinach sucrose-phosphate synthase (SPS) because of its role in regulation of sucrose synthesis in photosynthetic and heterotrophic tissues. A family of 12 independent transgenic lines was characterized in terms of foreign gene insertion, expression of spinach SPS, production of spinach SPS protein, and development of enhanced extractable V (max) SPS activity in leaf and fiber. Lines with the highest V (max) SPS activity were further characterized in terms of carbon partitioning and fiber quality compared to wild-type and transgenic null controls. Leaves of transgenic SPS over-expressing lines showed higher sucrose:starch ratio and partitioning of (14)C to sucrose in preference to starch. In two growth chamber experiments with cool nights, ambient CO(2) concentration, and limited light below the canopy, the transgenic line with the highest SPS activity in leaf and fiber had higher fiber micronaire and maturity ratio associated with greater thickness of the cellulosic secondary wall.

Cotton maturity, the degree of development of the fiber wall relative to its perimeter, is one of the main cotton quality attributes because it directly or indirectly affects most of the other cotton fiber properties. Mature fibers usually possess greater strength and better resilience. The presence of immature fibers may cause excessive fiber damage and waste during processing and may lower yarn strength. Immature fibers have also been recognized as one of the principal causes of the formation of neps, which result in a rough and uneven appearance in yarns and fabrics. Due to their relatively low dye affinity, the immature fibers in most neps easily show up as imperfections known as white specks in a dyed fabric, which leads to large financial losses. Hence, information about cotton maturity is desirable for cotton breeders and growers to enhance cotton fibers and to textile manufacturers to improve their quality control.Despite the importance of maturity, assessing it remains a serious problem for the cotton industry. The micronaire test is the only widely used method for cotton maturity measurement available to the industry today. Micronaire results are a combination of maturity and gravimetric fineness [1]. Although it is efficient, it provides only a combined measurement on maturity and fineness [2], which is not particularly useful for critical evaluations of cotton maturity. 1 The cross-section of a cotton fiber contains measurable information directly related to the maturity of the fiber. Much research has been conducted using image analysis technology to measure cotton maturity and other parameters from cotton fiber cross-sections [3][4][5][6]. In general, the success of a cross-section method using image analysis relies on two techniques: fiber cross-sectioning and image segmentation. The USDA Southern Regional Research Center (SRRC) developed an effective, but time-consuming cross-sectioning method that includes sampling, embedding and sectioning procedures [7,8].Abstract Information about cotton maturity is desirable to cotton breeders and growers for cotton enhancement and to textile manufacturers for quality control. This paper reports on the development of a dedicated system that facilitates direct, fast and high volume measurements of cotton maturity from longitudinal views, and the experimental results. The system examines cotton fibers in a projected 2-D image to measure the variations in fiber width, which reveal the severity of fiber convolutions, and the fiber translucence that reflects the thickness of the secondary wall. This paper describes the methodology for extracting these features and how they relate to cotton maturity.

A statistical evaluation was made of reflectance measurements obtained on raw cotton. A large variation was observed in unblended cotton samples either greige or dyed while slight blending reduced the variation, significantly. Instrument variation also calculated from part of the data gathered showed only slight (negligible) variation. Homogenization of samples prior to quantitative measurements was indicated and use of reflectance measurements from the wavelength of maximum absorbance seemed most sensitive to sample preparation changes.

Sticky cotton samples received at the Textile Research Center of Texas Tech University for processing had a significantly higher proportion of white colonies (many of which were coryneform bacteria) than non-sticky cotton samples, although the same kinds of organisms were present on both kinds of cottons. Four representative strains of coryneform bacteria were isolated from samples of both sticky and non-sticky cotton and examined for their ability to produce extracellular carbohydrates. When grown on thioglycollate agar, two of the strains produced copious amounts of extracellular polysaccharide in the form of a capsule. All four strains produced this material when they were grown in a liquid medium. Paper chromatography of the hydrolyzed capsular material revealed the presence of both glucose and galactose, and both glucose and galactose were present in hydrolyzed extracts of sticky cotton. Since previous investigators found carbohydrates were associated with stickiness in cotton, it is possible that capsule-forming coryneform bacteria contribute to stickiness when they constitute a significant proportion of the bacteria present on cotton.