Investigation of flax plant residue degradation processes under controlled laboratory conditions

Abstract

The effectiveness of enzymatic preparations based on cellulase, xylanase, alpha-amylase and pectinase activities for accelerating the decomposition of difficult-to-decompose flax plant residues during their incorporation into the soil or distribution on the surface was studied. The study was conducted in 2023 in the testing laboratory of phytodiagnostics and agrochemistry of АО “Agrodoktor”. The destruction of crop and root residues was assessed by the weight method, and the fractional composition of the undecomposed residues was determined by sieving through a sieve of different diameters. The dependence of decomposition intensity on the localization of crop residues in the soil or on its surface was revealed. When embedded in the soil, the best results were achieved using cellulase (+15.2% of the control), alpha-amylase (up to +16.7%) and pectinase (up to +27.7%). However, when distributing plant residues over the surface, the highest degradation rate was observed with the use of xylanase (+13.2%). The study revealed differences in the fractional composition of the crop and root residues of flax after the period of destruction. When distributing plant residues over the soil surface, the highest level of mineralization was recorded for variants using pectinase and xylanase, the percentage of plant residues that did not pass through a 6 mm sieve was 33.6 and 39.4, respectively, while the indicators for cellulase and amylase were at the control level of 45.3%. In the case of embedding plant residues in the soil, it was noted that cellulase, xylanase and alpha-amylase show similar results: the percentage of the large fraction varies from 8.7–9.5, pectinase shows a significantly lower indicator — 4.4, which indicates a deeper transformation of organic matter.