Skip to main content
ARS Home » Midwest Area » St. Paul, Minnesota » Plant Science Research » Research » Publications at this Location » Publication #151924
Title: VARIATION AMONG FORAGE TISSUES IN LIGNIN DEPOSITION AND ITS IMPACT ON CELL WALL DIGESTION

Author
item ENGELS, FERDINAND - WAGENINGEN UNIVERSITY
item Jung, Hans Joachim

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2003
Publication Date: 11/1/2003
Citation: Engels, F.M., Jung, H.G. 2003. Variation among forage tissues in lignin deposition and its impact on cell wall digestion [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. CD-ROM. Paper No. C06-ENGELS902660-ORAL.

Interpretive Summary:

Technical Abstract: Deposition of lignin in cell walls dramatically alters the potential degradability of forages. Growing and mature cells of some tissues (e.g., mesophyll, collenchyma) never develop lignified walls and remain rapidly and completely degradable. These tissues, especially in legumes, are rich in pectic polysaccharides. However, many tissues develop a lignified cell wall during maturation. Lignification always begins in the original primary wall and this wall layer becomes undegradable. Cellulose-rich wall layers are subsequently deposited. In maize sclerenchyma fibers the secondary wall becomes lignified whereas alfalfa phloem walls remain non-lignified. The secondary walls of both types of fiber cells remain degradable, although at a slow rate. Alfalfa develops an extensive stem xylem structure where both primary and secondary walls are highly lignified and virtually undegradable. Some alfalfa xylem fiber cells deposit an additional secondary wall layer that is less lignified and remains partially degradable. While some partially lignified cell wall layers in forages are potentially degradable, only individual cells that have been physically ruptured can be degraded because rumen microorganisms are unable to gain access to cell walls via hydrolysis of an intact lignified primary wall. Potential degradability of forage cell wall material is a complex function of diverse chemical structures and differences among tissues in wall development.