Ecology, biology and enzymatic activity of the rhizosphere planted with Larix decidua seedlings after addition of vermicompost

Abstract

The aim of this study was to determine the influence of Eisenia fetida vermicompost (VC) added to forest nursery soil. The chemical reaction in the soil and selected microorganisms, such as bacteria, fungi and nematodes, were assessed. Larch seedlings were cultivated for 2 years in pots with nursery soil as a control and VC-amended soil in two doses: 10% (V10) and 20% (V20) v/v. One important observation was the connection between the addition of VC and the improvement of the plant's biometry and a much higher level of mycorrhization with increasing Suillus sp. Vermicompost modified the nematode community by reducing plant parasitic nematodes, and significantly increasing bacterial and fungivorous, as well as predatory nematodes. Actinomycetes bacteria, which were present in a proportion of 2.2% in the control soil, increased to 10.5% in V10, and to 5.4% in V20. Bacillus spp. increased along with the amount of VC from <0.01% in the control to 2.2% in V10 and to 2.7% in V20. The C:P ratio correlated negatively while the C:K ratio and N-NH4 concentration correlated positively with the abundance of Bacillus spp. Toxigenic Penicillium spp. and Fusarium spp. were suppressed. The stability of VC-amended soil system with respect to enzymatic activity was rather high, except for o-diphenol oxidase which was strongly reinforced by the VC. The enzyme activity values for all enzymes were correlated with an improvement in the values of the microbiological, biometric and nematode parameters and increased mycorrhization. One favorable modification, which was manifested in better seedling growth, was the effect of VC on the development of Suillus-morphotype mycorrhizal fungi, fungal feeder nematodes and Bacillus spp. Vermicompost may therefore be recommended in practice as a method of sustainable management for soil protection in larch forest nurseries.