Premium
Tiller Development Influences Seasonal Change in Cell Wall Digestibility of Big Bluestem (A ndropogon gerardii)
Author(s) -
MacAdam Jennifer W,
Kerley Monty S,
Piwonka§ Edward J,
Sisson Donald W
Publication year - 1996
Publication title -
journal of the science of food and agriculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.782
H-Index - 142
eISSN - 1097-0010
pISSN - 0022-5142
DOI - 10.1002/(sici)1097-0010(199601)70:1<79::aid-jsfa469>3.0.co;2-0
Subject(s) - andropogon , tiller (botany) , forage , agronomy , growing season , biology , zoology , xylose , fodder , perennial plant , botany , food science , fermentation
The productivity of cool‐season forage grasses declines during mid‐summer in the southern corn belt of the USA. Warm‐season grasses are productive during this time, but their digestibility decreases from spring to summer. The objective of this study was to investigate cell wall factors contributing to the decline in in vitro dry matter digestibility (IVDMD) of big bluestem ( Andropogon gerardii Vitman) leaf blades from late spring (May) to mid‐summer (July) under three harvest regimens. Under frequent defoliation, decrease in cell wall digestibility accounted for much of the change in IVDMD. Among cell wall constituents, only xylose and alkali‐labile phenolic acids increased significantly from spring to summer. Change in p ‐coumaric acid content and the ratio of p ‐coumaric acid to ferulic acid were both negatively correlated with the decrease in cell wall digestibility. While glucose and uronic acid digestibility decreased from spring to summer, xylose was consistently the least digestible of the cell wall monomers. In warm‐season grasses grown under constant environments, tiller development causes an increase in leaf structural tissue, and the data suggest that the seasonal decline in leaf blade cell wall digestibility was partially due to tiller development.