Effect of Zero herbicide and methods of autumn tillage on yield and formation of the photosynthetic apparatus of oil flax varieties

Abstract

Abstract. The purpose of the research was to identify the effect of the Zero herbicide introduced after harvesting the predecessor, the methods of autumn tillage on the productivity, photosynthetic activity of oil flax plants of the varieties VNIIMK 620 and Severnyy. Research Methods. Studies on the tasks were carried out in 2016–2018 in the pilot plots of JSC “Uchkhoz Iyul’skoye Izhevskaya GSKHA” according to generally accepted methods. The previous crop for oil flax in the crop rotation was winter triticale. The experiments were laid on sod-podzolic medium loamy soil. Results. It was revealed that the Zero continuous herbicide introduced after harvesting the precursor contributed to an increase of 0.6 c/ha or 7.0 % in seed yield, relative to the yield in variants without herbicide. The autumn tillage of KN-4, PLN-4-35, BDT-3 soil ensured an increase in the yield of seeds of oil flax varieties VNIIMK 620 and Severnyy 1.8–3.2 c/ha or 23.1–41.0 %, respectively, relative to the similar indicator in options without chaffing tillage. Subsurface autumn tillage of KN-4 soil in terms of seed yield of oil flax varieties VNIIMK 620 (10.8–11.3 c/ha) and Severnyy (10.3‒11.3 c/ha) was not inferior to seed yield (10.7–10.9 c/ha and 10.9–11.3 c/ha, respectively) in the variant with dump processing PLN-4-35. Small tillage BDT-3 reduced seed yield by 1.4‒1.6 c/ha (13‒15 %) in the variety VNIIMK 620 and by 1.4‒1.8 c/ha (12‒16 %) in the variety Northern, in comparison with productivity in options with KN-4 or PLN-4-35. The treatment of the stubble of the precursor with the Zero continuous herbicide contributed to an increase of 0.7 thousand m2/ha of the area of leaves of oil flax varieties in the flowering phase, photosynthetic potential (FP) by 41 thousand m2×day/ha during the growing season, relative to similar parameters in the options no herbicide. The highest AF during the growing season of plants of oil flax varieties was formed in the variants with autumn tillage KN-4 and PLN-4-35, which significantly exceeded the similar indicator by 97–375 thousand m2×day/ha for VNIIMK 620 and 84–423 thousand m2×day/ha for the Severnyy variety in the control variant. Scientific novelty. In the conditions of the Middle Cis-Urals, for the first time, effective techniques for autumn tillage of sod-podzolic medium loamy soil in the technology of cultivating flax varieties of oilseed VNIIMK 620 and Severnyy were revealed. The effect of Zero herbicide, methods of heap, subsurface, small chaffinch tillage on the yield and photo-synthetic activity of oil flax varieties was established.