Viscoelastic properties of plant cell walls. IV. Physical meaning of parameter K in mathematical formulation for stress-relaxation and load-extension processes

Article type: Research Article

Authors: Fujihara, Suguru^a | Yamamoto, Ryoichi^b | Masuda, Yoshio^b

Affiliations: [a] Science Education Institute of Sakai City, Mozuakahata, Sakai 591, Japan | [b] Department of Biology, Faculty of Science, Osaka City University, Sumiyoshi-ku, Osaka 558, Japan

Note: [] Accepted by: Editor N. Kamiya

Abstract: When the function ϕ(K, A; B) is defined by the equation ϕ(K,A;B)=B(1+AB)1+B−KA the stress-relaxation process at a fixed strain has been represented in the previous papers of this series as follows: S=bk·lnϕ(K,tp;t+Tmk)ϕ(K,tp;t+Tok)+ck where S is stress, tp is pre-extension time, and the parameters Tok, Tmk, bk, ck, and K are constants. As we have reported, the parameters Tok, Tmk, bk, and ck can be defined physically. However, the physical meaning of the parameter K has remained unclear. This study leads to the conclusion that parameter K can be defined as being equal to the pre-extension time, tp, in the stress-relaxation experiment. Thus, the stress-relaxation curve and the effect of auxin pretreatment on a hysteresis loop in a stress-strain curve at a constant rate could be represented well by the calculated values.

Keywords: Auxin, cell wall loosening, stress-relaxation, oat, pea, stress-strain

DOI: 10.3233/BIR-1979-16602

Journal: Biorheology, vol. 16, no. 6, pp. 387-396, 1979