Influences of Some Environmental Conditions upon the Growth and Development of the Flax Plant, Linum usitatissimum L.

Abstract

Flax plants (var. Saginow No. 1) were grown in pots under different conditions as follows : control (soil moisture content 20.6 % per dry soil), moistened (grown in moistened soil, 34.8 %), dried (grown in dry soil, 10.7 %), and shaded (grown under shading, 22.4 %). The stem length of the plants became larger and stem diameter increased in the moistened plot. In the later stage of growth, elongation of the plant in the control and moistened plots ceased due to the reproductive growth. However, the shaded plot did not bloom, and the stem continued to elongate. On the other hand, in the dried plot, the flowering was not uniform according to the temporary elongation of the plant after every irrigation. Thus, number of leaves decreased after the flowering stage in the control and in moistened plots, but in the shaded and dried plots, the number of leaves did not decrease until the harvest time. Dry weight of above-ground parts of the plant became larger in the moistened plot and smaller in the dried plot. However, dry weight of boll in the moistened plot decreased more than the control plot, because of the reduction of the ratio of reproductive growth to vegetative growth in the moistened plot. Number of fiber-cells found in the cross section of middle part of the stem became larger in the control plot than other experimental plots. Although in the moistened and shaded plots, number of fiber-cells was reduced to one half of those of the control plot, diameter and thickness of cell-membrane of the fiber-cells were noticeably developed in the moistened plot compared to other plots. From the consideration of the above-mentioned causes, fiber percentage in the dry weight of stem became larger in the moistened plot and became smaller in the shaded and dried plots. The fiber obtained from the moistened plot was better than that from the control plot because of the higher content of α-cellulose and the lower content of β-and γ-cellulose. However, from the dried and shaded plots the fibers of poor quality were obtained because of the lower content of α-cellulose and the higher content of lignins than that of the control plot. Particularly, from the shaded plot the fiber of the worst quality was obtained.