Soil chemical properties and mineral nutrition of Latvian accessions of Trifolium fragiferum, a crop wild relative plant species

The aim of the present study was to compare soil chemical composition and aspects of mineral nutrition of several accessions from different geographically isolated sites in Latvia of Trifolium fragiferum L., a crop wild relative plant species. Eight geographically isolated micropopulations of T. fragiferum in Latvia were identified, and material was sampled for analysis of plant-available mineral nutrient concentrations in soil and mineral nutrient concentrations in leaf tissues. Micropopulations of T. fragiferum were associated with rivers, lakes and the sea, thus also outside typical coastal or inland-located salt-affected grassland habitats. Soil concentration of plant-available mineral nutrients showed significant variation between different sites, ranging from 59% for N to 193% for Ca. Variation in mineral element concentration in plant leaf tissues was relatively lower. Multivariate analysis showed that sites with similar localization on river shores or in coastal areas had similar characteristics, as these were grouped together according to both soil mineral nutrient availability as well as leaf tissue mineral element concentrations. T. fragiferum can be characterized as a species able to maintain mineral homeostasis in leaf tissues irrespective of large variability in soil plant-available mineral nutrient concentrations and different levels of soil pH. Together with general resilience to environmental constraints, this allows to predict a relatively good conservation status of T. fragiferum in Latvia in spite of rather limited number and size of the geographically isolated micropopulations.