Effect of herbicides on yield and quality of straw and homomorphic fibre in flax (Linum usitatissimum L.)

• Impact of herbicides (Afalon, Basagran and Glean) on yield and quality of flax fibre was studied.
• The best weeds reduction, highest straw yield and fibre quality was after the use of chlorsulfuron.
• The best fibre quality was obtained after chlorsulfuron application than on other test objects.
• Bentazon, due to its phytotoxic effect on flax, reduced the homomorphic fibre yield and its quality.
• Linuron applied pre-emergence resulted the longest fibres and highest fibre content in flax straw.

Fibre flax (Linum usitatissimum L.) is a very poor competitor with weeds, and to obtain acceptable yields, weeds should be effectively controlled. Very little information is available on the tolerance of flax to herbicide applications. Types of applied herbicides determine not only the yield of flax but can also affect yield of fibre, its quality and may affect processes (physical, chemical and enzymatic) used in the refining of homomorphic fibres to increase their thinness and divisibility. Presented basic field research was carried out in the years 2011–2012. In the studies the impact of three herbicides (with a.i. linuron, bentazon and chlorsulfuron) was examined on the control of weeds, course of vegetation and yield and quality of flax homomorphic fibre. The applied herbicides had a significant impact on the weed control, the length of the vegetation, straw yield, the percentage of fibre in the straw, weight and length of the fibre and its thinness and divisibility. The lowest number and mass of weeds and the highest flax straw yield and fibre quality was obtained after chlorsulfuron application. Bentazon, despite its high herbicidal effectiveness, reduced both the amount and quality of fibre yield when compared to chlorsulfuron, due to its phytotoxic effect on flax. Pre-emergence linuron application resulted in the longest fibres and highest fibre content in flax straw.