|Evaluation of inactivated fungal extracts as defense inducers against fungal diseases in strawberry|
Sebastián Moschen: Instituto Nacional de Tecnología Agropecuaria (INTA), EEA Famaillá.
<div>Argentina is one of the four main strawberry producers in South America. This crop is susceptible to a large number of diseases and fungal infections are the most important biotic stress. Nowadays, there is a trend towards the use of natural biocontrol agents instead of synthetic fungicides in order to enhance immunity to microbial infections in crops. The aim of this work was to evaluate the protective capacity of inactivated microbial extracts against two of the main fungal pathogens in strawberry (<em>Botrytis cinerea </em>and<em> Colletotrichum acutatum</em>). Fungal extracts of local strains (<em>Colletotrichum acutatum </em>and<em> Acremonium strictum</em>) were obtained and thermally inactivated (121°C, 20min). The extracts were applied by aspersion on Arabidopsis and strawberry leaves. After 5 days of induction, the plants were infected with a suspension of <em>B. cinerea</em> and <em>C. acutatum</em>. The infection progress was evaluated during 30 dpi showing a significant decrease in plants pre-treated with the microbial extracts. The capacity of inducing a <em>Pattern Triggered Immunity</em> response in Arabidopsis was also evaluated by growth inhibition using Col-0 and <em>FLS2, EFR</em> and <em>CERK1</em> triple mutant (<em>Fec</em>) seedlings and by qPCR evaluating the expression of defense related genes such as PR1, FRK1, WRKY70 and WRKY 53. This work demonstrated that the inactivated extracts were able to induce protection against fungi, which provides a valuable and natural alternative for the biocontrol in agronomically important crops.</div>