Data supporting the findings of Lebedev (2024) Organic carbon stock and soil properties in a transgenic pear orchard in comparison to different land use types. Global Change Biology.

Soil organic carbon (SOC) affects both the functioning of terrestrial ecosystems and agricultural production. Land use change has a greater impact on SOC stocks than climate change. The application of genetic engineering in agriculture provides numerous benefits, but transgenic plants can have undesirable impacts on the environment including soil properties. Unlike annual crops, transgenic trees grow in one place for a long time and their effects on the soil can accumulate. This study evaluated the effect of 10-11-year-old transgenic pear trees on SOC stocks, soil physicochemical properties, enzyme activity and microbial biomass in the field. Transgenic plants were obtained by conventional transformation (<i>uidA</i> reporter gene) or retransformation (herbicide resistance gene <i>bar</i>), which increases the risk of unintended effects. Transgenic pear plots were compared with grassland, cropland and mature (23 years) pear orchard. Transgenic plants had no effect on SOC stocks and such soil physicochemical properties as pH, nutrient content, soil texture. The impact of retransformants on soil enzymes was more pronounced compared to single transformants. The effect of transgenic pear plants on microbial biomass (MBC, MBN, and MBP) was negligible. The distance from pear trunks (0.2 or 1 m) had an effect on the activity of some enzymes. SOC stocks were maximum in mature orchard (80.1 Mg ha^-1) and fallow (78.7 Mg ha^-1). These values were much lower in the young orchards and meadow. In terms of nutrient content, meadow soil was inferior to agricultural systems. Fallow was the leader in the activity of most soil enzymes, followed by meadow and then pear orchards. In general, transgenic pear trees did not adversely affect soil quality. This first study of transgenic fruit trees and retransformed stacked plants provides an assessment of their soil biosafety and improves our understanding the impact of transgenic and traditional agrosystem functioning on the environment.