Some Physiological Factors Influencing the Production of Flax Fiber Cells1

Abstract

Photo-micrographs from seedling flax stems prove that the flax fiber cells arise from the pericycle. Flax plants eventually attain the greatest height in short periods (10 hours) of light per day but elongate and mature the quickest in long periods (18 hours) of light per day. The short-day plants yielded 8 times as much fiber as the long-day plants. The height of a flax plant more than anything else determines how much fiber it contains. A complete nutrient solution was necessary in water cultures to produce the tallest seedlings. Nitrogen, particularly in combination with other elements, produced the longest stems in field-grown seedling plants, but results from these same fertility plats showed that plants fertilized with phosphorus and potassium equalled or surpassed the nitrogen plats at maturity. Combinations of potassium and nitrogen seem to be desirable for best results. Seedling field-grown plants gave the highest percentages of fiber with the following treatments: 4-0-0, 4-16-0, and 4-16-8. The percentage of fiber in the mature field-grown plants was twice as great as it was in the seedling plants. Some of the results substantiate the conclusions of other workers that phosphorus increases the fiber percentage and that nitrogen decreases it, but there were exceptions to this rule. The number of fiber cells increases after seedling plants are 6 weeks old. The number of fiber cells in field-grown seedling plants increased with additions of fertilizers, but no significant increase or decrease was obtained in mature stems for any fertilizer treatment when compared with the check. The area of fiber cells as seen in cross-section is closely correlated with the area of stem, and fertilizers tending to increase the area of stem and probably the number of fiber cells will increase the area of fiber cells. Water cultures which produced the best yields of fiber were high in phosphorus and medium high in potassium. The 0-16-8, 4-16-8, 8-16-8, and 4-16-16 treatments gave the largest yields of fiber in cu. mm. per stem for seedling field-grown flax plants. Mature field-grown plants gave the largest yields of fiber in cu. mm. per stem with the following treatments: 4-0-8, CaCO3 6000 pounds, 0-0-0, and 0-0-8. Medium high yields of fiber in cu. mm. per stem were obtained with the treatments 4-16-16 and 4-16-8. A study of the various cultures leads to the conclusion that a fertilizer analysis closely approximating a 4-16-8 is the most desirable for fiber flax where little is known regarding the soil requirements.