0000000000341129
AUTHOR
Lelde Grantina-ievina
Impact of Green Manure and Vermicompost on Soil Suppressiveness, Soil Microbial Populations, and Plant Growth in Conditions of Organic Agriculture of Northern Temperate Climate
The impact of organic amendments on the soil microorganisms and plant growth and health in conditions of organic agriculture of Northern temperate climate was analyzed. Some case studies dealing with green manure or vermicompost amendments are discussed giving deeper analyses of the vermicompost impact on plant growth. The first case study is about the impact of green manure on soil microbial populations and soil suppressiveness against such pathogens as late blight, potato scab, and black scurf of potato in organic agriculture. The second case study is about the use of vermicompost in organic starch potato cultivation. Significantly higher numbers of all groups of analyzed cultivable micro…
Impact of barley (Hordeum vulgare L.) transgenic line H228.2A on substrate and rhizosphere microorganisms and the possibility of horizontal gene transfer
Numerous investigations have been carried out to determine the impact of genetically modified plants, such as potato, maize, alfalfa and tobacco, on soil microorganisms and the results are contradictory. We applied classical microbiology methods to study quantitative changes of bacterial and fungal abundance in substrate and rhizosphere from barley (Hordeum vulgare L.) transgenic line H228.2A containing Rpg1 and bar genes, and its parent nontransgenic variety ‘Golden Promise’. In addition, molecular biology methods were used to determine, if horizontal gene transfer from barley transgenic line to soil bacteria has occurred under experimental conditions by screening bacterial genomes for the…
The impact of wood-derived biochar on the survival of Trichoderma spp. and growth of Secale cereale L. in sandy soil
The interrelations between biochar (BC) and soil microbiota remain unclear. Addressing this will be important for understanding how BC affects soil properties and plant growth. Here, we tested the ...
The impact of wood-derived biochar on the survival of Trichoderma spp. and growth of Secale cereale L. in sandy soil
The interrelations between biochar (BC) and soil microbiota remain unclear. Addressing this will be important for understanding how BC affects soil properties and plant growth. Here, we tested the influence of wood-derived BC with immobilised Trichoderma viride on rye Secale cereale L. in sandy soil. We found that the addition of BC leads to a significant (P 2+ and Mg2+, as well as a decrease in the concentration of Al3+, irrespective of BC particle size and the presence of T. viride. Plant growth was stimulated in the presence of small (<2 mm) particle-sized BC. Fungal diversity, as well as an absolute and relative abundance of Trichoderma spp., was tested by cultivation-dependent metho…
Comparison of soil microorganism abundance and diversity in stands of European aspen (Populus tremulaL.) and hybrid aspen (Populus tremuloidesMichx. ×P. tremulaL.)
The use of short rotation forest tree species is increasing worldwide. The hybrid aspen (Populus tremuloides Michx. × P. tremula L.) is one of the suitable tree species under the climatic conditions of the Baltic region. The cultivation of these trees on former agricultural soils differs from agricultural practices with reduced soil tillage and is characterized by increased demand of nutrients, which in long term can cause changes in the soil microbial populations. The aim of our investigation was to compare soil microbial populations in hybrid aspen and European aspen (P. tremula L.) stands in four sampling plots with aspen age ranging from 10 to 46 years. The abundance and diversity of so…
Potential risk evaluation for unintended entry of genetically modified plant Propagating material in Europe through import of seeds and animal feed – the experience of Latvia
Significant attention has been drawn to the adventitious and technically unavoidable presence of genetically modified (GM) organisms in the food and feed imported into the European Union (EU), while the potential presence of GM seeds in material for cultivation is less studied. Here we report a study from an EU member state, Latvia, during years 2017–2018 regarding monitoring for the presence of GM seeds in certified seed and animal feed material. Eighty-two and 28 samples of seeds intended for cultivation were analyzed in 2017 and 2018, respectively. One soybean sample contained MON40-3-2 soybean seeds (0.09 ± 0.01%) and one maize sample contained MON810 maize seeds (0.08 ± 0.01%). In addi…