Autumn foliar feedings of winter rapeseed are needed to form a powerful root system, accumulate sugars for successful overwintering and optimize mineral nutrition at the start of the formation of yield components, which takes place from autumn. The differentiation of generative organs in winter rapeseed plants takes place at the rosette stage (6–8 leaves): balanced mineral nutrition in this period and a longer period of bud formation at the top of the root collar ensure higher productivity. Nutrient deficiency at this time is one of the main reasons for reduced rapeseed yield, especially with late sowing dates.
For successful overwintering, plants should be provided from autumn with key mineral nutrients, in particular boron. Acute boron shortage in the autumn period leads to negative consequences: deformation and hollowness of the root system and inhibition of its growth and development; insufficient development of vascular bundles and the growing point; reduced sugar accumulation and transport to the root collar; worsened frost and winter hardiness of plants and overwintering in general.
Boron shortage most often shows on soils of light texture, waterlogged, acidic and limed soils, and in periods of severe drought. Based on this, we suggest the following options for foliar feeding of winter rapeseed with ECOORGANIC fertilizers:
- On crops with visual signs of boron shortage - ECOLINE Boron (Organic) 1.0 l/ha.
- When signs of stress appear on rapeseed plants - ECOLINE Phosphite (K) 1.0 l/ha + ECOLINE Boron (Premium) 1.0 l/ha. Combining boron with amino acids promotes quick boron uptake and sugar accumulation in the root collar in the unstable weather of autumn.
- On soils of light texture, eroded soils, where magnesium and boron shortage may appear - ECOLINE Boron (Premium) 1.0 l/ha + ECOLINE Magnesium (Chelates) 1.0 l/ha + ECOLINE Phosphite (K) 1.0 l/ha.
- On fields with a pH below 5.0 molybdenum shortage may appear; plants then lag in growth and development and leaves are smaller. For such areas it is better to use the boron fertilizer ECOLINE Boron (Opti) 1.0–1.5 l/ha.
Trial at Ahroprodservis LLC, Ternopil region. K – control (no foliar feeding), 1 – ECOLINE Phosphite (K) 0.5 l/ha + ECOLINE Boron (Organic) 1.0 l/ha. Assessment results on 15.09.2020 (10 days after application): weight of 3 plants: K – 75 g, 1 – 160 g; root collar diameter: K – 0.5 cm, 1 – 0.7 cm