Search

As an alternative to reduce the use of agrochemicals, plant extracts can be a better choice in the control of phytopathogens. In this study, we tested the effects of Magnolia dealbata Zucc. crude extracts on the bacterial growth of Pectobacterium carotovorum and Pseudomonas cichorii, both micro-organisms of phytopathogenic relevance. In addition, our other aim was to explain the influence of the seasons and source organs at different maturing stages in the bioactivity of the extracts. Several ethyl acetate and ethanol crude extracts obtained from leaves, bark, flowers, polyfollicles and seeds were tested using the disk-diffusion method. The ethyl acetate extract of M. dealbata polyfollicle collected in summer inhibited the development of P. carotovorum and P. cichorii to the same extent as the tetracycline positive control (Z=1.0690, p=.285 and Z=1.278, p=.201, respectively) while the ethyl acetate seed extract inhibited the growth of P. carotovorum, but did not equal the effect of tetracycline (Z=2.022, p=.043). It can be concluded that the extracts obtained during summer showed the highest inhibition of these bacteria. [ABSTRACT FROM AUTHOR]