INFLUENCE OF METEOROLOGICAL INDICATORS ON OATS YIELD IN CROPPING ROTATIONS

The studies were carried out to assess the influence of predecessors in crop rotations and nutrition background on the formation of oat yields under different weather conditions. The work was carried out in a stationary two-factor experiment in 2016–2020 in the conditions of the Middle Urals on dark gray heavy loamy soil. The experimental design included the following options: crop rotation (factor A) – green manure (green manure fallow (rapeseed), wheat, oats, peas, barley), grain-grass rotation with a share of legumes of 40% (peas, wheat + clover, clover 1 g.p., barley, oats); background nutrition (factor B) – without mineral fertilizers (control); N30P30K36 (on average per 1 ha of crop rotation area - mineral background); N24P24K30 in combination with green manure and straw (organomineral background). The lowest harvest of oat grain was noted in 2016 in severely arid conditions (GTC = 0.63); it varied depending on the predecessor and nutritional background from 1.30 to 1.70 t/ha. The highest productivity of grain fodder crops was observed in 2017-2018 with a hydrothermal coefficient of 1.8...2.0. In the control variant, it varied in the range from 3.09 to 3.69 t/ha, when applying fertilizers – 4.20…5.52 t/ha. In slightly dry conditions in 2020, the productivity of oats in crop rotations in the control was lower than under favorable weather conditions by 30%, and against the background of fertilizers - by 24...33%. In general, the productivity of the grain forage crop in the control depended little on the predecessor in crop rotations. The placement of oats as a second crop after clover on mineral and organomineral nutrition backgrounds ensured a noticeable increase in grain harvest in relation to green manure crop rotation (the second crop after plowing rapeseed), with the exception of 2016. On average, over the years of research, the increase in oat grain in grain-grass crop rotation was 0. 55…0.56 t/ha. The correlation between the productivity of grain fodder crops and the amount of precipitation and the GTC value was positive (r=0.82...0.95), and with the temperature regime during the growing season - negative (r=-0.88...-0.97).