Plant extract of Ruta graveolens standardized in furanocoumarins: resistance elicitorin rice plants against Magnaporthe Oryzae

Abstract

We explored furanocoumarin compounds extracted from herb Ruta graveolens to suppress the blast rice disease by eliciting rice systemic resistance pathways. The plant material was subjected to the extraction method by percolation with 80% hydroethanolic solution, which allowed the obtaining of the furanocoumarins, that were monitored by HPLC.Tests were carried out in vitro and in greenhouse. The experimental design was entirely randomized with 24 treatments and 3 replicates.The concentration of 6.75 mg/mL of extract provided the highest chitinase activity in the period of 24 and 48 hours before inoculation with the pathogen, with the latter referring to 2.67 and 2.70 mg of glic.h -1.mg prot-1, respectively, for chitinase and 6.04 and 7.84 mg of gly.h 1 .mg prot-1, respectively for β-1,3-glucanase.The concentrations of 0.7 mg/mL psoralen and 1.2 mg/mL bergapten strongly induced the defense mechanisms of rice plants translating in substantial reduction of disease severity in more than 90%.These results underscore the potential application of a plant extract containing furanocoumarins to mitigate the bursting burden of rice by increasing the mechanisms of systemic resistance. The use of plant extracts allows the reduction of the disease through several different mechanisms, which makes this strategy very efficient and innovative.