ARS | Publication request: Cell Wall Content and Composition of a Stiff Stem Sorghum Accession

Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 22, 2001
Publication Date: N/A

Technical Abstract: Stalks of the sorghum (Sorghum bicolor (L.) Moench) plant introduction, PI431592, were observed to remain very flexible until anthesis and then develop an extremely hard stalk that is resistant to lodging. A field experiment was designed to determine cell wall composition of PI431592 and a check forage variety, 'Atlas', at several stages of maturity (vegetative, ,boot, soft-dough, mature). First year results show little or no difference in Klason lignin, glucose, xylan, and minor sugars concentrations at any maturity stage. However, as plants matured cell wall concentration of PI431592 decreased very little between the boot stage and anthesis (586 to 555 mg/g), while cell wall concentration of Atlas decreased much more significantly (605 to 418 mg/g). Since secondary cell walls are not known too be broken down and carbon mobilized for other uses, a decline in cell wall concentration with advancing maturity should indicate accumulation of cytoplasmic components at a faster rate than cell wall material. Microscopic examination of limited numbers of internode cross-sections of the two sorghum lines showed no apparent increase in density of thick- walled sclerenchyma tissue in Atlas with advancing maturity. Apparent density of thick-walled sclerenchyma tissue in the rind region of PI431592 continued to increase throughout maturity stages.