Weedness sowing of fiber flax in crop rotation with short rotation

Abstract

 Relevance. The aim of the work was to study the influence of predecessors cultivated in three crop rotations with a short rotation on the weedness of fiber flax crops and the yield of flax products. The study was carried out in field experiments in 2016–2019, on medium and weakly acidic soddy-podzolic light and medium loamy soils of the Tver region with a high phosphorus content.

Methods. As the precursors of fiber flax, vetch-oat mixture and white mustard were cultivated with post-cut cultivation of white mustard for green fertilization, and also repeated sowing of fiber flax was carried out in the same field for three years in a row after the predecessor of barley.

Results. As a result of the studies, it was found that the greatest lowering the weediness of fiber flax crops and an increase in the yield of flax products was observed in the crop rotation with the cultivation of white mustard for green fertilization after the precursor of the vetch-oat mixture for green fodder and the introduction of the biofungicide Sternifag after the precursor of barley with the addition of 12 kg/ha of ammonium nitrate. There was a decrease in the number of stems of couch grass (Agroperon repens) by 2.8 times, a significant increase in the yield of fiber flax — by 5 dt/ha a compared with repeated cultivation of fiber flax in the same field and by 1.4 dt/ha compared with cultivation after barley without the use of biofungicide. At the same time, the yield of flax straw was 29.1 dt/ha, of flax stock 22.4 dt/ha, of flax fiber — 6 dt/ha. In the crop rotation with the sowing of fiber flax after barley in the same field for three years in a row, there was a decrease in the yield of flax fiber by 0.3 and 0.8 dt/ha, including fiber scutched flax — by 1.6 and 1.7 dt/ha in comparison with cultivation in crop rotations with post-harvest use of white mustard for green fertilization.