Effect of various biochar rates on winter rye yield and the concentration of available nutrients in the soil

Abstract

From 2012 to 2014 a field experiment was conducted on a podzolic soil. The aim of the study was to evaluate the yield and weed infestation of winter rye canopy depending on three biochar rates (10, 20 and 30 t/ha). The biochar was pyrolyzed from wheat straw at 350-650°C. After 12, 24, and 36 months from biochar incorporation into the soil pH, total carbon (C) and some elements in soil were determined. Additionally phytotoxicity of soil solid phase was assessed by the commercial toxicity bioassay - Phytotoxkit. The addition of biochar had a positive influence on grain yield of winter rye, which was related to the nutrient application in the form of biochar. The highest grain yields were obtained when biochar was applied at the rate of 20 t/ha. The air-dry weight of weeds in the rye crop grown in the biochar-amended plots was lower compared to the control plots. Incorporation of biochar into the soil at the rates of 20 and 30 t/ha caused a significant increase in the soil content of total C as well as of available P, K, Mg, Fe and B, relative to the control treatment. Moreover, the biochar-amended soil had higher pH because of the relatively high concentration in the biochar (pHKCl 9.9). The assessment of substrate toxicity revealed that biochar applied at the rates of 10 and 20 t/ha had no negative effects on the germination of Lepidium sativum L.

Keywords

• straw coal
• chemical properties of soil
• secale cereal
• yield components