HEAVY METAL TOLERANCE AND ACCUMULATION POTENTIAL OF COASTAL ACCESSIONS OF TRIFOLIUM FRAGIFERUM, A PROMISING FORAGE SPECIES

Abstract

The aim of the present study was to examine heavy metal tolerance of different wild accessions of strawberry clover, T. fragiferum, a promising forage species, in comparison to a commercial cultivar, and to find out if there is a tendency to accumulate heavy metals in above ground parts of strawberry clover plants. Seeds from four geographically isolated wild populations of T. fragiferum in Latvia as well as cv. 'Palestine' were used to establish experiment in controlled conditions using substrate gradient of Cd and Pb. Similar to closely related species T. repens, T. fragiferum showed high tolerance to heavy metals Cd and Pb and excluded heavy metals from above ground parts. Some physiological differences were evident in respect to morphological responses of different accessions to the two heavy metals as well as regarding heavy metal accumulation potential in different plant parts. It was concluded that when cultivated in unpolluted soils, shoots of T. fragiferum can be considered safe as forage for animal consumption.