Elemental and Nutrient Composition of Cotton Plant Parts

To increase the knowledge on chemical composition of different cotton plant parts, in this study, whole cotton plants were collected at mid-season and just before harvest (pre-defoliation). These plant samples were separated into six (mid-season) or eight (pre- defoliation) biomass fractions: main stems, leaf blades, branches, petioles, roots, and the reproductive part (or bur, peduncles+bracts, and seeds). The contents of macro (P, Ca, K, Mg, Na, and S) and micro (Fe, Zn, Cu, and Mn) elements, crude protein, acid detergent fiber, neutral detergent fiber, and acid detergent lignin in these biomass fractions were determined using standard procedures. We found growth stage affected the relative contents of some, but not all, measured parameters. Regression analysis revealed that the contents of some parameters were well correlated with each other, but other parameters were quite independent of each other. The information reported in this work would be helpful in assessing nutrition management practices for cotton production. It also provides some insight on utilizing the cotton crop byproducts as soil amendments and other off field industrial raw materials.