Jorge Henrique Chagas

Crescimento vegetativo e produção de óleo essencial de hortelã‑pimenta cultivada sob malhas

The objective of this work was to evaluate the growth and the content, yield, and chemical composition of the essential oil of peppermint (Mentha piperita) grown under different nets in Lavras, MG, Brazil. Peppermint plants were grown in five environments: full sun, black net, aluminet net, blue net, and red net, all with 50% of irradiance. The experimental design was a completely randomized block with four replicates and five plants per plot. The evaluated parameters were: vegetative growth, content, yield, and chemical analysis of the essential oil. Peppermint plants grown under full sun and black and red nets produced higher dry leaf biomass and higher essential oil content and yield. However, in full sun, the essential oil of the plants had higher contents of menthol and, under black and blue nets, of menthophurane. Therefore, it is possible to manipulate plant growth and yield and chemical composition of the essential oil of peppermint with cultivation under nets or full sun.

BIOMASS PRODUCTION, YIELD AND CHEMICAL COMPOSITION OF PEPPERMINT ESSENTIAL OIL USING DIFFERENT ORGANIC FERTILIZER SOURCES Produção de biomassa, rendimento e composição química do óleo essencial de hortelã-pimenta usando diferentes fontes de adubação orgânica

Mentha x piperita L. is an aromatic and medicinal species belonging to the family Lamiaceae that is popularly known as peppermint. The aim of this study was to evaluate the effects of organic fertilizer sources on the biomass production, yield and chemical composition of peppermint (Mentha piperita L.) essential oil. The experiment was conducted using a completely randomized design (CRD) with a 2 x 5 factorial scheme, two sources of manure (cattle and poultry), five doses (0, 3, 6, 9 and 12 kg m-2) and four replicates. Different doses of cattle and poultry manure significantly affected plant biomass production and the responses of other variables, including leaf area, leaf weight ratio, leaf area ratio, root:shoot ratio, yield and chemical composition. Organic fertilizer doses of 9.0 kg m-2 cattle manure and 8.3 kg m-2 poultry manure to obtain the maximum total dry biomass. The highest yield of essential oil was obtained by applying 11.8 kg m-2 poultry manure. Differences in the chemical composition of the essential oil were observed for only three components (menthone, pulegone and menthyl acetate) without significant changes in the menthol content.

Produção, teor e composição química do óleo essencial de hortelã-japonesa cultivada sob malhas fotoconversoras

Foi avaliado o efeito da intensidade e da qualidade espectral da luz transmitida pelas malhas fotoconversoras em relacao ao crescimento, teor e composicao quimica do oleo essencial das plantas de Mentha arvensis. Foram realizadas duas avaliacoes, aos 85 dias apos o plantio e aos 80 dias apos a rebrota das plantas. O delineamento experimental utilizado foi inteiramente casualizado, dispostos em quatro tratamentos e cinco repeticoes, sendo cada parcela composta de tres vasos (uma planta por vaso) em cada corte. Os tratamentos foram caracterizados por plantas de hortela-japonesa cultivadas a pleno sol e sob malhas com 50% de sombreamento na cor preta, vermelha ou azul. Foram avaliados a biomassa seca de folhas, caules, parte aerea, raizes e estoloes e total, razao raiz/parte aerea, area foliar total, razao de area foliar, area foliar especifica, numero de brotacoes, teor, rendimento e composicao quimica do oleo essencial. O crescimento da planta, teor e rendimento de oleo essencial sao mais afetados pela intensidade do que pela variacao espectral da luz imposta pelas malhas. O sombreamento de 50% provocado pelas malhas e excessivo, independente da cor. A composicao quimica do oleo essencial nao foi afetada consideravelmente pelas malhas.