Allelopathic tolerance in broad bean (Vicia faba L.) accessions to Sorghum halepense extracts

Natalia Georgieva

Abstract: Due to the growing importance of organic farming and environmental protection, more and more attention should be paid to ecological interactions between species, and less to the use of pesticide products. The present study aimed to determine the allelopathic tolerance of ten Vicia faba accessions (Fb 1896, Fb 1903, Fb1929, Fb 2481, Fb 2486, Fb 3270, BGE 002106, BGE 029055, BGE 032012, BGE 046721) to extracts of Sorghum halepense. Aqueous extracts (in concentrations of 1.0, 5.0 and 10.0%) from shoot and root weed biomasses were compared with distilled water used as control. Germination and initial growth parameters, including the percentage of seed germination, length and weight of the germ, percentage of inhibition, tolerance index and seedling vigour index were reported. Analysis of variance showed significant influence of the factors “accession” and “concentration of the extracts” of S.halepense on the seed germination and initial growth parameters, and the influence of the type of weed extract was significant only for seed germination. The inhibitory effect of the extracts ranged from 7.7 to 100% in terms of seed germination, and it was in limits 3.6 ÷ 100% and 7.1 ÷ 100% regarding germ length and weight, respectively. As a whole, as the extract concentration increased, the depressive effect on the studied parameters enhanced. The summary effect of the allelopathic action of Sorghum halepense on all parameters studied (represented by GGE-biplot analysis) determined accessions Fb 3270, Fb 2481 and Fb 2486 as exhibiting higher tolerance, unlike Fb 1929, BGE 032012, BGE 002106, Fb 1903 and Fb 1896 which were more sensitive.

Keywords: allelopathy; Sorghum halepense; tolerance; Vicia faba

Date published: 2021-06-30