The objective of this work was to evaluate peroxidase activity and protein concentration in the defence system expression of common bean Phaseolus vulgaris L., submitted to different potencies of homeopathic preparations. The treatments were composed by: Arsenicum album, Staphisagria, Silicea and Sulphur, in the 6, 12 and 18 CH potencies, compared to the controls. The bean seeds were sown in pots which were kept in a greenhouse and the treatments were applied to them at 1% in distilled water since the sowing day, with intervals of 15 days until the R7 stage. The first evaluation was performed at 15 e 60 days after sowing, after artificial mechanical damage. Protein concentration and the activity of guaiacol peroxidase (POD) and ascorbate peroxidase (APX) enzymes were determined. Differences between treatments and controls were estimated by Glass Delta effect size analysis. Staphisagria 12CH induced greater increase in protein concentration on bean leaves. The Induction on APX and POD activities were observed in leaves treated with Sulphur in all tested potencies. The Glass Delta effect showed undulatory behaviour, sometimes acting positively, sometimes negatively, throughout all evaluations. Homeopathic preparations have the potential to induce biochemical defence mechanisms in beans, acting as resistance elicitors.

The aim of this study was to evaluate the efficiency of rock powder applied isolated or associated with egg-laying hen manure as a source of nutrients for maize crop; and to evaluate the effect of application form in the efficiency of this sources in improve crop yield. The experiment was composed by eight treatments, distributed in a randomized block design and in factorial design 4 (A) x 2 (B), with four replicates. In factor A, the different sources of nutrients were allocated: rock powder; rock powder + egg-laying hen manure; egg-laying hen manure; and control; applied on the soil surface or incorporated with harrow. The doses used were 2 and 10 Mg ha-1 of rock powder and manure, respectively. Were evaluated: foliar nitrogen (N) and phosphorus (P) contents; extraction of N and P; and maize yield components. There was no interaction between the factors tested. The use of egg-laying hen manure isolated or associated with rock powder resulted in higher foliar P content, higher P extraction and increase in maize yield components, except for the number of plants per linear meter and cobs per plant. The application form did not affect the maize yield components, but when applied on the surface it increased foliar P content and P extraction. Rock powder is efficient in promoting better maize yield only when associated with manure. The incorporation of rock powder does not increase its efficiency in providing nutrients to the plants.