Effects of Shading on the Growth and some Properties of Fiber Cells of Flax Plant, Linum usitatissimum L.

Abstract

Flax plants (var. Saginaw No. 1) were grown in pots under different light intensities as follows: 100% (control), 43% (shaded I) and 17% (shaded II) of the solar radiation. The stem length of the plants grown in the shaded conditions became larger according to the larger elongation of internode of the stem. Dry weight of above-ground parts and bolls of the plant became smaller as the light intensity decreased. Number, diameter and cell membrane thickness of fiber-cells found in the cross section of the stem became smaller as the light intensity decreased. Particularly, the development of thickness of the cell membrane was greatly decreased by the lower light intensity. Thus, the fiber yield per plant and the fiber percentage in the dry weight of the stem became poorer as the light intensity decreased. The contents of α-cellulose in the crude cellulose were decreased by the shade treatment. On the contrary, the contents of (β+γ)-cellulose and lignin became higher by the same treatment. As the results, the shaded conditions not only reduce the fiber yield in the flax plant but also induce the reduction of the quality of the fiber.