Abstract:

When fungicides are mixed togather the level of activity can be influenced in three ways; there can be antagonistic, additive, or synergistic interactions between the partners. In order to reveal the the characteristics of the synergistic and antagonistic mixtures on fungicide, that article through the tests of mycelial growth rate,going on the determination of the synergies of the partners of Thiram and Tebuconazole to Fusarium graminearum. Selected the synergistic(SM, EC500.0331μg/mL) for the 7:10 ratio and antagonistic(AM, EC502.2937μg/mL) for the the 9:4 ratio mixtures, through the tests of electrical conductivity to detecte the changes of the permeability of the cell membrane, trying to compare the differences of the synergistic and antagonistic mixtures. Dealing with Hyphae within the cells of synergistic mixture , after 60min the conductivity increased, which shown that there is a phenomenon of the hyphal cell inclusions leakage constantly;and antagonist mixtures deal with the mycelial cell permeability,which is less than that of the contrast. The determination of reducing sugar ,chitinase, soluble protein content of three cell inclusions to Hyphae within the cells and found that the different trend over time: the reducing sugar content of synergistic mixture so that in 25 h, the decline for the contrast of 18.91%; chitinase activity in between 5~20 h increased; soluble protein contently increased by the subsequent and decline in the short term. In the conditions of antagonistic mixture, Hyphal cell containing content changes nearely the contrast or has the same trend to a single partner over time. The basic of selection and evaluation on the synergistic mixture should be the determination on synergies of fungicide mixture and mechanism of synergistic and antagonistic mixtures.