Searching for Promising Flax Genotypes with High Fiber Quality

This research aimed to identify promising genotypes with high-quality flax fiber to create new varieties. The experiments were carried out in 2022–2024 in the Tver Region on sod-podzolic soil. The material for the research included 28 samples of the flax gene pool of domestic and foreign selection. Varieties differing in the spinning capacity of flax fiber were used as standards: Orshansky 2 (excellent) and Slavny 82 (unsatisfactory). The flax varieties Atlant (Russia) and Lira (Republic of Belarus) combined tallness (97.5 and 89.6 cm, respectively) and a high yield of total (16.6 and 17.6 c/ha) and long (12.7 and 14.0 c/ha) fiber; based on the results of technological evaluation, they were assigned to groups 1 and 2 according to the spinning capacity (the estimated relative breaking load is 16.5 and 16.2 gf/tex). At the same time, the Atlant variety had the highest long (scutched) fiber number in the experiment (14.1), which is 3.3 numbers higher than the standard Orshansky 2 variety. The lowest long fiber number has been recorded for the Vesta variety (Republic of Belarus) (8.6); as a result, despite the high potential yield of total fiber (17.2 c/ha), the harvesting of long fiber from this variety proved to be minimal in the experiment (6.2 c/ha), which is comparable to the Slavny 82 variety (7.5 c/ha). The most interesting varieties for the production of high-quality cellulose are the high-yielding varieties Tost 5 and Dobrynya (Russia) and Thaler (Republic of Belarus), which differed in a uniform distribution of fiber along the length of the stem (“rise” of 0.45–0.47 mm), which is important for the formation of a uniform flax raw material in terms of maturation and, as a consequence, low-sticky flax fiber.