Immature cotton

ABA was discovered by three independent lines of research.548 Cams and coworkers found that an auxin inhibitor, abscisin, was involved in the abscission of immature cotton fruits. However, Ohkuma and other... 

FIGURE 5.4 Transmission electron micrograph of a section of primary cell wall from very immature cotton fiber. The black dots are immuno-labels of pectin molecules. (Credit to Kevin Vaughn, USDA-ARS, Stoneville, MS.)... 

This statement is also applicable to the causes of the most frequent manifestation of damage, namely stains. Statistical analysis of 258 cases of damage by stains resulted in 29 types of cause, each represented in more than seven cases. The most common types of cause gave frequencies in the range from 7-8%. These are, for example, stains caused by mechanical and chemical influences, dyestuffs, grease or oU, silicone and dead or immature cotton. 

There are many publications on the subject of neps and their detection, for example Furter and Frey, "and on the determination of the degree of maturity of cotton. " Here, only the principle of the so-called rcd/grccn test will be briefly described, since it is easy to carry out in any textile laboratory - and it gives a quick idea of the proportion of immature cotton. It does not correlate well with other tests of maturity.On the other hand, cotton samples which show the same degree of maturity after the usual maturity test with the air-flow method often show subsequent differences in depth of dyeing,thus underlining the importance of this dyeing test. 

Rippon, J. A., Improving the dye coverage of immature cotton fibres by treatment with chitosan. I. Snc. Dvers Colourists. 100 (1984), 298-303. 

If immature cotton embryos have the ability to germinate, demonstrated by their behaviour when isolated, why do they not do so in the intact developing seed Vivipary, the germination of immature seeds within the fruit of the parent plant, is rare in cotton and when it occurs it is lethal. Prevention of vivipary might be explained by the fact that coincidental with the capacity of the embryo to germinate precociously, and perhaps to produce messenger RNA for proteinase... 

Genencor s cellulases improve fabric appearance by removing surface fibrils and pills and reducing dead and immature cotton. This prevents subsequent pilling during wash and wear upgrading overall textile quality. 

FIGURE 25.10 Derivative spectra of matured and immature cotton. 

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