Nitric acid solution after treating miscanthus as a growth regulator of seed peas (Pisum sativum L.)

Abstract: All over the world, miscanthus is positioned as an extremely promising and rapidly renewable cellulose- containing raw material for the production of a large number of substances of chemical and biotechnological synthesis. The Institute for Problems of Chemical and Energetic Technologies of the Siberian Branch оf the Russian Academy of Sciences has been developing its own methods of treating miscanthus using diluted solutions of nitric acid. While the amount of a waste solution (liquid phase) is 20 times greater than the target product — a solid phase -- intended for enzymatic hydrolysis and further microbiological synthesis of bioethanol, bacterial cellulose and other valuable products. The hypothesis states that a nitric acid solution after treatment with miscanthus, which was neutralized with ammonium hydrate (hereinafter referred to as the preparation), is a combined lignohumic fertilizer. Testing this hypothesis has required studying the growth-regulating activity of the preparation using the example of sowing pea seeds. The results show that, depending on the degree of dilution and the exposure time, the preparation acts in two ways: either as a stimulant or as a growth inhibitor. Thus, at a dilution rate of 1:10, the preparation acts as an inhibitor, and at a dilution rate of 1:1,000,000, its effect ceases. The working range includes the dilution rate between 1:100 and 1:10,000, when an increase in germination energy and rate is observed by 2–6% compared to the control and root growth is stimulated by 21–29%, i.e. an auxin-like growth-stimulating effect is observed. With prolonged endurance during the 4th day, the preparation showed a growth-inhibiting effect, indicated by the decrease in the germination energy and rate, the length of the stems and roots of the sowing pea. The new preparation showing growth-stimulating activity under certain conditions, supposedly confirms the hypothesis that it is a combined lignohumic fertilizer.