The refractive index of the unlignified middle lamella is 1.516 in both primary and secondary xylem and differs from the expected value of 1.504 for pectin.
This value does not vary between earlywood and latewood, or between chlorite and per-acetic preparations. The refractive index of holocellulose varies among specimens from different parts of the stem and it is recommended that this value be determined on matched samples for each specimen. The lower value in the S2 is attributed to either residual carbohydrates or chemical differences in the lignin of the two regions. The refractive index of lignin in the middle lamella region is found to be 1.604 while in the S2 region it is 1.596. This report investigates sources of experimental error involved in the quantitative measurement of lignin concentration in the layers of the tracheid cell wail using interference microscopy. OECD workshop - supplement to Volume 40 (2010).IUFRO working Party S07-02-09, Phytophthora Diseases in Forests and Natural Ecosystems - supplement to Volume 41.
0 kommentar(er)
