2022-04-062022-04-062013-122013-12December 2https://hdl.handle.net/2346/88997The structure and organization of cellulose in developing cotton fibers from TX55 and TM-1 cultivars at varying developmental stages from 10 to 56 days post anthesis (DPA) were investigated using Wide angle X-ray Diffraction (WAXD) and Universal Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (UATR-FTIR). The potential use of infrared (IR) crystallinity indices (1429/897 and 1372/2900), integrated intensities of the vibrations 667 and 887 cm-1 and cellulose content as indirect estimators of XRD crystallinity were investigated. With fiber development, XRD crystallnity and crystallite size normal to 200 plane increased whereas Full Width at Half Maximum (FWHM) values decreased indicating increased alignment and decreased molecular disorder in 200 plane as cellulose biogenesis progresses. Changes in WAXD parameters could detect the onset of higher rate of cellulose biosynthesis and thereby estimating the timings of different developmental stages of fiber development. These results were further confirmed by FTIR and cellulose content data. IR crystallinity indices, cellulose content, integrated intensities of the vibrations 667 and 897 cm-1 showed good correlation with XRD crystallinity. Therefore, these parameters could be used as good indirect estimators of XRD crystallinity in developing cotton fibers. Determination of percent crystallinity using FTIR is a simpler method compared to XRD, which involves time-consuming curve fitting and baseline subtraction proceduresapplication/pdfengX-Ray DiffractionFourier Transform Infrared SpectroscopyCelluloseCrystallinityCotton FibersThesis2022-04-06Access is not restricted.