Allelopathy Journal

Experiments were carried out in order to study the effect of C. majus shoot and root water extracts on germination and radicle length of cucumber and Solanum nigrum under laboratory conditions. In pot experiments, the effect of shoot and root extracts was studied on economically important viruses (Obuda pepper virus, ObPV; Potato virus Y, PVY; Alfalfa mosaic virus, AMV; Sowbane mosaic virus, SoMV Zucchini yellow mosaic virus, ZYMV) in their hosts (Nicotiana tabacum cv. Samsun, N. tabacum cv. Xanthi-nc, Chenopoodium amaranticolor, C. quinoa, Cucumis sativus cv. Delicatesse). In bioassay, it was concluded, that the inhibitory effect on radicle length of cucumber was stronger, than that on germination. Root and shoot water extracts of C. majus in all concentrations - except 10 fold dilution of shoot extract - significantly reduced germination of S. nigrum. Shoot water extracts - especially at higher concentrations - had the strongest inhibitory effect. In pot experiments, it has been seemed that in systemic host-virus relations root and shoot extracts of C. majus did not inhibit virus infection. Opposite effect, enhanced virus concentration was observed in some cases. C. majus root water extract reduced by 50% the number of local lesions on N. glutinosa leaves due to ObPV infection. Both root an shoot extracts of C. majus reduced by more than 50% the fresh weight of S. nigrum. C. majus root water extract significantly reduced the fresh weight of AMY infected C. amaranticolor and SoMV infected C. quinoa plants, while shoot extract had no effect in this respect. No significant difference between untreated virus infected and treated virus infected plants had been observed in fresh weight in other host-virus relations.