Abstract Abstract: The formononetin biostimulant may be an option for reducing P fertilization once it stimulates mycelial growth of arbuscular mycorrhizal fungi and increases plant ability to take up nutrients through the roots, especially phosphorus. The objective of this study was to evaluate the effect of formononetin associated with phosphorus fertilization in maize. Field experiments were conducted in a randomized block design with a 3 × 4 factorial arrangement (0, 50 or 70, and 140 kg ha-1 P2O5; and formononetin application rates: 0, 25, 50, and 100 g ha-1), with four replications. Formononetin (100 g ha-1) increased the mycorrhizal colonization rate up to 30% in maize in the first four weeks after emergence when no P fertilizer was applied, and to 17% when 50 or 70 kg ha-1 of P2O5 were applied. The application of 50 and 100 g ha-1 of formononetin significantly increased plant height, ear height, and grain yield (22% - 76%) when no P fertilizer was applied. The use of formononetin in the field stimulates mycorrhizal colonization, has a positive effect on maize yield, and reduces the need for P fertilizer application in maize. However, this effect was evident only at low P soil contents.

Objetivou-se com a realização deste trabalho avaliar a influência da adubação orgânica na produção de massa e no teor do óleo essencial de Aloysia triphylla (L'Hérit) Britton. O experimento foi conduzido em casa de vegetação e foram aplicadas cinco doses de esterco bovino curtido: 0, 3, 6, 9 e 12 kg m-2, com quatro vasos por repetição, dispostos em delineamento inteiramente casualizado. Após 198 dias de cultivo, foi realizada a secagem em estufa e extração por hidrodestilação do óleo essencial a partir de folhas secas, em Clevenger modificado. As plantas de A. triphylla crescidas com 12 kg m-2 de esterco bovino tiveram maior rendimento de massa. Maior teor de óleo essencial foi verificado nas plantas crescidas com 9 kg m-2 de esterco bovino.

This work evaluated the influence of organic manure in biomass production and in essential oil content of Aloysia triphylla (L'Hérit) Britton. Plants growing under greenhouse received five tanned cattle manure rates: 0, 3, 6, 9 and 12 kg m-2 with four pots per replication, in randomized complete design. After 198 days of growth, plants were dried and the essential oil was extracted from leaves by the Clevenger's modified apparatus. The highest biomass was presented by plants cultivated with 12 kg m-2 and the highest oil yield was obtained from A. triphylla treated with 9 kg m-2 of cattle manure.