Produção e rendimento do óleo essencial de Salvia officinalis L. tratada com homeopatias no controle do Aspergillus welwitschiae

Abstract

The use of homeopathic preparations in agriculture has been tested as an alternative to ecologically clean technology in vegetable production. Its use was recognized in the insertion of the Brazilian Normative Instruction No. 7 in 1999, as an agricultural input in the principles of food production. Salvia officinalis L. is a spice, aromatic and medicinal plant that can be grown in brazilian soil and its essential oil has, among other characteristics, an antifungal potential, which has been tested in the control of phytopathogens such as Aspergillus welwitschiae, responsible for the red rot of the sisal. This study aimed to evaluate the growth, yield and yield of essential oil Salvia officinalis L. treated with homeopathic medicines, as well as to evaluate its antifungal potential under the pathogen Aspergillus welwitschiae. The homeopathic treatments used were: Staphysagria 12 CH, Sulphur 12 CH, Homeopathic Complex and water used as control, constituting 4 treatments with 60 repetitions, totaling 240 experimental units. At the end of 90 days, the aerial part of the plants was harvested, and then the aerial part fresh mass (MFPA) was determined. Subsequently, the material was submitted to oven drying with forced ventilation. The dry matter for essential oil extraction (MSEO) was determined, which was submitted to the extraction of the essential oil for yield calculation (ROE). The essential oil sample was tested for inhibition of mycelial growth of A. welwitschiae isolates by the minimum inhibitory concentration (MIC) test at concentrations of 160; 80; 40; 20 and 10 μl/mL-1, evaluation of fungicidal/fungistatic effect and by agar diffusion test, with the essential oil of plants treated with Sulphur 12 CH. The collected data were submitted to analysis of variance and regression using the Computational Program R at 5% probability. The obtained results show that for the variable H of the plants, the homeopathic complex induced a lower growth of the plants when compared to the control. However, it was observed that all homeopathies used were able to promote the reduction of MSEO accumulation. For the MIC test, all concentrations tested inhibited fungal mycelial growth. To evaluate the fungicidal/fungistatic effect, it was verified that the essential oil obtained from plants treated with Homeopathic Complex and the essential oil obtained from control plants showed fungicidal effect up to 20 μl/mL-1. The essential oil extracted from plants treated with Staphysagria 12 CH was effective up to 40 μl/mL-1. Already the essential oil extracted from plants treated with Sulphur 12 CH, proved to be efficient in all concentrations tested. Regarding the agar diffusion test, it was verified that as the tested concentrations of S. officinalis L. essential oil treated with Sulphur 12 CH increased, there was an increase in mycelial growth inhibition. It was concluded that the homeopathies tested reduced the dry mass production of the plants without influencing the essential oil yield, which presents antifungal action against Aspergillus welwitschiae fungus, when treated with the homeopathic medicine Sulphur 12 CH.