Activation of biochemical defense mechanisms in bean plants for homeopathic preparations

To evaluate the potential elicitor of homeopathic preparations on bean plants cv Carioca, homeopathics of Corymbia citriodora, Calcarea carbonica, Silicea and Sulphur in dynamisations 12, 24, 30 and 60CH were applied by pulverization throughout the aerial part. Samples of leaf tissue were taken at 6, 12, 24, 48 and 126 h after the treatment (HAT) to analyze the activity of peroxidase (POX), catalase (CAT), chitinase (CHI) and -1.3-glucanase (GLU), and fifteen days after the application for the total contents of chlorophyll a and b. For the induction of phytoalexin phaseolin, seeds of the same genotype were germinated in the presence of respective treatments, and the production of phytoalexin quantified spectrophotometrically. All treatments increased the activity of POX, CAT, QUI and GLU, in at least one of the schedules evaluated in comparison to the control. The treatments C. citriodora and C. carbonic did not alter the contents of chlorophyll but induced the accumulation of phaseolin. Silicea and Sulphur caused significant reduction in the levels of chlorophyll a and b. The induction values were superior to the trading inductor (harpin), indicating that these homeopathies may come to be utilized as elicitor treatments on bean plants. The results indicate the potential of the treatments applied in the induction of biochemical mechanisms of defense in the bean plants.