Study shows essential oils as a promising alternative in the control of dry bubble disease

By Tamara Leite dos Santos, doctoral student of of the postgraduate program in agricultural microbiology, Eduardo Alves and Eustáquio Souza Dias, professors of the Federal University of Lavras, Lavras – MG, Brazil

The study entitled “Essential oils in the control of dry bubble disease in white button mushroom”, published in Ciência Rural, v. 47, n. 5 of 2017, aimed to estimate the influence of various essential oils extracted from Melissa officinalis, Thymus vulgaris, Origanum vulgare, Eucalyptus globulus, Cinnamomum zeylanicum and Syzygium aromaticum on the in vitro development and their uses. Therefore, analysis was performed of the L. fungicola isolates in vitro and the best oils were tested in vivo. Besides, the Agaricus bisporus – L. fungicola interaction was confirmed by scanning electron microscopy (SEM). The researchers were interested in testing other ways to combat the fungus Lecanicillium fungicola, a serious infection agent in mushrooms, which causes significant losses in mushroom production (BERENDSEN, et al., 2012).

Cinnamon and clove oils, from the concentration of 0.4%, and 0.8% thyme inhibited the mycelial growth of the pathogen. The germination of conidia was inhibited by cinnamon oil at all concentrations, and clove and thyme at 0.4% and 0.8%, respectively. The application of the essential oils after infestation in the experiment in vivo brought lower incidence of the disease in the mushrooms. Electron microscopy showed that there is an infection with approximately 19 hours.

According to researcher Tamara Leite, the results of the study suggest that there is a need to apply the essential oil or the combination of essential oils, sequentially, throughout the production cycle. “Probably, the greater incidence of the disease in the applied treatments pre-infestation occurs as a function of the volatility of the oils used. Alongside this, the fact that there is no control of when spores are present and that the treatment effects are variable depending on the genetic variability of the pathogen suggest that we should work with a combination of oils”, she comments.

Tamara claims that the use of essential oils can be a promising tool in the cultivation of pesticide-free mushrooms. Currently, the dry bubble disease is treated through the use of fungicides, based on recommendations made in other countries, since there are no products of this order registered by the Brazilian Ministry of Agriculture (MAPA – IN 18, 2009). However, the researcher stresses the need for more research on the practical use of essential oils in the production of mushrooms, which investigate the cost-benefit ratio and application effectiveness.

References

BERENDSEN, R. L., et al. Effects of fluorescent Pseudomonas spp. isolated from mushroom cultures on Lecanicillium fungicola. Biological Control [online] 2012, vol. 63, no. 2, pp. 210-221 [viewed 02 July 2o17]. DOI: 10.1016/j.biocontrol.2012.07.012. Available from: http://www.sciencedirect.com/science/article/pii/S1049964412001636

Mapa (Instrução Normativa Conjunta Nº 18, de 28 de Maio de 2009). Ministério da Agricultura, Pecuária e Abastecimento. 2017. Available from: http://www.agricultura.gov.br/assuntos/sustentabilidade/organicos/legislacao/portugues/instrucao-normativa-no-18-de-28-de-maio-de-2009-alterada-pela-in-no-24-11-processamento.pdf /@@download/file/Instru%C3%A7%C3%A3o%20Normativa%20N%C2%BA%2018%20de%2028%20de%20Maio %20de%202009%20(alterada%20pela%20IN%20N%C2%BA%2024-11%20-%20processamento).pdf

To read the article, access it

SANTOS, T. L., et al. Óleos essenciais no controle da doença bolha seca em champignon. Cienc. Rural [online]. 2017, vol. 47, no. 5, e20160780 [viewed 02 July 2o17]. DOI: 10.1590/0103-8478cr20160780. Available from: http://ref.scielo.org/9p6qn9

External link

Ciência Rural – CR: <http://www.scielo.br/cr>