ALLELOPATIC COMPATIBILITY OF COMMON BEAN AND COMPANION CROPS

Abstract

Purpose. To investigate the allelopathic compatibility of common bean seeds and companion crops, to establish interaction patterns using water extracts from seeds and other plant parts of common bean and companion crops. Methods. Laboratory, statistical. Results. Biotest: interaction of germinating seeds of bean and companion crops in Petri dishes. Biologically active substances from winter and spring triticale seeds (the bean seeds/seeds of companion crops ratio was 1:10) negatively affected bean seedlings, which was seen from all parameters under investigation: hypocotyl length (with the root included), length of the longest adventitious root, the adventitious root number, and true leaf length (with epicotyl included). At a ratio of 1:5, winter triticale-induced inhibition of hypocotyl growth was enhanced up to 38 %, while, on the contrary, spring triticale had a neutral effect on this parameter. A stimulating effect (106 %) of spring triticale seeds on the true bean leaf length (with epicotyl) was noted. For winter and spring triticale in a ratio of 1:1 (compared to the control – without seeds of companion crops), inhibition of the growth of the hypocotyl with the root by 21 % and the true leaf with the epicotyl by 10–9 %, respectively, is observed. Biotest: germination of bean seeds in a water extract from whole seeds of bean and companion crops in Petri dishes. Water extract from spring triticale seeds in a ratio of 1:2 had the greatest stimulating effect on the tap root and the first leaf lengths; winter triticale extract in a ratio of 1:4 had the greatest effect on the adventitious root an epicotyl lengths; bean extract in a ratio of 1:2 had the greatest effect on the epicotyl length. Biotest: germination of bean seeds in a water extract from vegetative mass, roots and post-harvest residues of bean and companion crops in Petri dishes. Water extracts from roots of bean, winter and spring triticale weakly inhibited the main bean root elongation. A neutral allelopathic effect on the bean seed germination was exerted by extract from post-harvest residues of spring triticale. A water extract from top parts of bean had a negative allelopathic effect on germinating bean seeds, indicating self-incompatibility of this crop. Conclusions. The laboratory tests showed that biologically active substances from seeds of both winter triticale and spring triticale at a ratio of 1:10 were toxic for bean ssedlings. Combined germination of bean and spring triticale seeds at a ratio of 1:5 had a more positive effect compared to other ratios of seeds of companion crops, and combined germination of bean seeds with spring and winter triticale seeds at a ratio of 1:1 demonstrated very similar parameters of germinating bean seeds. It was found that water extracts from bean and spring triticale in a ratio of 1:2 and from bean and winter triticale (1:4) had a clear allelopathic effect on the bean parameters. Water extracts from winter triticale (1:1) and spring triticale (1:4) were more toxic to bean seedlings. Water extracts from roots of bean, winter and spring triticale weakly inhibited the main bean root elongation. A water extract from the aboveground parts of bean had a negative allelopathic effect on the germinating seeds of bean, indicating self-incompatibility of this crop. A neutral allelopathic effect on the germination of bean seeds was exerted by extract from post-harvest residues of spring triticale. Combined germination of seeds of bean and companion crops in the laboratory allows for assessments of peculiarities of seed germination and mutual influence of components as early as at the initial stage, for selection of crops for growing in heterogeneous fields aimed at forming a highly productive agrophytocenosis.