Influência bacteriana em roseira: redução do mofo cinzento e melhoria em características agronômicas

Abstract

Floriculture is a branch of agribusiness that ranges from cut flowers to potted plants and foliage. Its demand has grown in the international market, which has led many professionals to seek technologies that enable the improvement of productsin terms of quality, beauty and durability. In Brazil, floriculture has been growing steadily, with a 4% increase in market value in 2018 compared to the previous year, reaching a total of R $ 7.2 billion. Among the cut flowers, roses stand out in the national and international market. For its production are used chemicals applied on a large scale, which can cause damage to the environment and the farmer. Therefore, an alternative that has been consolidating is the use of beneficial microorganisms, which can act in disease control, in promoting plant growth and in stems durability. Inoculation with growth promoting bacteria can increase yield and improve flowers quality, as well as influence the quantity and quality of oils produced. Thus, the objective of this work was to study the potential of growth promoting bacteria in management of gray mold and rose production. The first experiment was based on selection of bacteria for the control of Botrytis cinerea, the main pathogen of the rose bush, after stalk harvest. This resulted in selection of four bacteria that were selected due to their potential to produce bioactive and volatile antifungal compounds, which helped control the pathogen and increased the durability of flower stems when applied directly to flower stems obtained at the harvest point. From this selection, the second experiment was carried out, which aimed to study the effect of the four selected bacteria on the production of floral stems and on the quantity and chemical composition of the essential oils. The application of the selected microorganisms for the production in greenhouses not only improved the agronomic characteristics related to the production as the size of the stems and the flower buds, but also increased the durability of the flowers, besides increasing the essential oils produced, stimulating the production of compounds of interest to the chemical industry, such as Carophylene Oxide, α-Selinene, Limonene and α-Farnesene. Thus, this work has demonstrated the potential of using growth promoting bacteria to protect gray mold and to produce red roses from “Tonight” and “Black Prince” varieties.