Film stimulating coatings for seeds based on silica mixtures

Abstract

For improve the quality of harvests, modern farms in many countries widely use fertilizers of mineral and natural origin. To mitigate the negative impact on the environment, they try to minimize the amount of mineral fertilizers applied to the soil by creating composite systems. In particular, powdered composite materials are known based on highly dispersed silica and microquantities of mineral fertilizers, which are applied to the surface of the seeds by dusting. The aim of this work was to develop a new generation of film stimulating coatings based on mixtures of hydrophobic AM-1-300 and hydrophilic A-300 silicas, mineral fertilizers and bioactive components. Mixtures of hydrophilic and hydrophobic silicas in the ratio 1:1 and 1:2 were used to obtain a pasty composite with the given stimulating properties; colloidal starch solution; medium salts of mineral acids, bioactive components “Humifriend” and fungicide “Fital”. Such composite systems were applied directly to the surface of sowing material, grains of wheat variety “Natalka” before sowing in sand and on filter paper, according to DSTU 4138-2002. During the study, the following parameters were measured: seed germination energy, germination and morphological characteristics of wheat germs, which consisted in measuring the length of the root and stem. It is shown that when editing certain amounts of bioactive components to the composition of stimulating pasty composites, it is possible to program the properties of future films and powders: to increase morphological characteristics, uniformity of germination and fungicidal characteristics of composites. It has been found that the presence of mineral fertilizers in pasty composites of silicas mixtures 1:1 and 1:2 has a positive effect on the uniform germination of wheat seeds in the sand and on the filter paper. Instead, the presence in the pastes of the active ingredients “Fital” and “Humifriend”, regardless of the environment where the seeds germinated, there is a significant slowdown in the growth of wheat germ in both environments. It has been found that an excess of hydrophilic silica in the pasty composite leads to the development on the surface of the grains of mycosis lesions, regardless of the germination environment. Therefore, stimulant pastes based on 1:2 silica mixtures must contain fungicides of mineral or biological origin.