The economic and ecological effect of special foliar fertilisation to the sunflower crop

Abstract

Nowadays, special foliar fertilisation has become widespread because it is distinguished by a high economic efficiency, especially in: conditions of soils with low accessibility of nutrients, calcareous and alkaline soils where foliar fertilisation represents an efficient mean of curative treatment for iron, zinc and manganese deficiencies; semiarid areas where the water and thermal stress drastically limits the accessibility of plants at nutrients from the soil; the reproductive period of the plants, when the root activity is low. The paper presents the results obtained by applying special foliar fertilisers, under pedoclimatic conditions in Iași. These foliar fertilisers were tested on the sunflower crops, HS Rapid and HS PR 475 hybrids, in order to correct the micronutrients disorders (Mo and B) on inbred sunflower lines in hybrid sunflower seed production, having the following chemical composition: ▪ ICF 624 (g element or substance / kg of fertilizer): 183 N, 62 P, 114 K, 21 S, 0.4 Fe, 0.5 Mn, 0.35 Zn, 0.25 Cu, 0.01 Co, 0.80 B, 0.15 Mo; ▪ ICF 624 a (g element or substance / kg of fertilizer): 217 N, 73 P, 96 K, 21 S, 0.4 Fe, 0.5 Mn, 0.35 Zn, 0.25 Cu, 1.50 B, 0.66 Mo. The tested fertilisers have determined a significant specific yield increase and have assured a high environmental protection effect, quantified as the net exports of macronutrients from soil with the obtained yield increases. Thus, the average yield increases were between 292-587 kg/ha and the specific yield increases were between 19.50-39.15 kg seed / kg or liter of foliar fertiliser. From a practical point of view, using this method of special foliar fertilisation, we obtain besides the important production increases, significant effects of reducing the phenomenon of chemical pollution of the environment. However, due to the high nutrient consumption, the use of such a method and mean, under poorly supplied soils with nutrients (without basic fertilization in the soil), can contribute to the degradation of soil fertility. Therefore, it is recommended the concomitant use of soil fertilisation and foliar fertilisation with these special compositions, the optimal ratio between basic and foliar fertilisation being 90:10. The paper also presents and analyses a series of indicators related to the cultivation and to the production of sunflower seeds in Romania.

Keywords

• economic
• environment
• romania