The Second Foliar Feeding of Sunflower: the Basis of a High Yield

Balanced mineral nutrition combined with integrated plant protection can ensure fuller use of the genetic potential of the hybrids grown and so a higher yield of good quality. The period from the formation of 6–8 leaf pairs is extremely important in the crop's ontogeny. At this time the main yield element of the crop, the head, is in full formation, and a shortage of key mineral nutrients and stresses of various kinds adversely affect the future yield. Our company, a producer of foliar nutrition fertilizers, offers a fairly wide line of high-quality fertilizers on the market, whose effectiveness has been proved many times. Among them, compositions containing L-α-amino acids, with which plants overcome stress faster and form a higher yield, have become especially popular.

Sunflower is a boron-loving crop. A shortage of boron during growth of vegetative mass and formation of vascular bundles and flowers adversely affects yield. Since boron is hardly mobile in the plant, it is desirable to apply the needed dose in parts, in two or three passes.

For the 6–8 leaf pair stage the composition Ecoline Boron Premium is the best fit. Besides 140 g/l of organic boron, this product contains 10 grams/l of L-α-amino acids, which ensure quick overcoming of stress factors. The rate for one application is 0.5–1.0 l/ha.

An important role in the mineral nutrition of this crop belongs to phosphorus and potassium, which promote the formation of a healthy plant. On soils with low content and low availability of zinc, zinc feeding is quite effective for root systems. Since this spring the company has been producing a new composition Gros Amino Zinc with 80 g/l of zinc and 60 g/l of L-α-amino acids. The recommended dose for feeding sunflower at the 6–8 leaf pair stage is 1.0 l/ha. It can be applied separately or with the addition of 1.0 l/ha of Ecoline Phosphite K. As functional diagnostics results show, plants need additional feeding with macro- and microelements that are hard for plants to access under insufficient moisture supply. Stress factors have a great influence on the active development of young sunflower plants. Moisture shortage on the one hand, and the phytotoxic effect of soil and rescue herbicides on the other, can cause substantial losses in both yield and grain quality. Even on crops of hybrids resistant to one or another herbicide group, signs of stress are observed on plants in the first days after their application. And every such stress reduces the potential yield by 5–15%! Therefore plants need help to overcome stress factors quickly. The optimal measure in this period is the use of special foliar nutrition fertilizers, anti-stress products, containing free L-α-amino acids.

We suggest using the microfertilizers Ecoline Phosphite K-Amino at 1.5–2.0 l/ha on such crops. The fertilizer contains 70 g/l of L-α-amino acids that plants quickly absorb and that bring them out of stress. A test of one of the sunflower feeding schemes by Pioneer Nasinnia Ukraina in 2017 in Ternopil region (table) showed that foliar feeding promoted higher yield component indicators and a tangible yield gain with a high payback.