'BIOLOGICAL EVALUATION OF 24-HYDROXY-4-CHOLEN-3-ONE AS A POTENTIAL TOOL FOR CONTROLLING ROOT KNOT NEMATODE INFECTION'

KRONBERG M.F.; DEL VALLE E; CRISTIAN R. RODRIGUEZ; MUNARRIZ ELIANA; ADRIANA VELEIRO; CASTRO OA; SANTILLAN V; MODENUTTI CARLOS; GERARDO BURTON

Buenos Aires

Congreso; Reunion conjunta de sociedades de biociencias 2017; 2017

SAIB/SAIC

BIOLOGICAL EVALUATION OF 24-HYDROXY-4-CHOLEN-3-ONE AS A POTENTIAL TOOL FOR CONTROLLING ROOT KNOT NEMATODE INFECTIONThe root-knot nematode Meloidogyne incognita is one of the most damaging parasites because it infects almost all cultivated plants..Second-stage juveniles (J2) penetrate the root and migrate to the vascular cylinder inducing the development of root knots. J2 becomes sedentary and undergoes three molts to become an adult female that lays eggs. After egg eclosion, J2 larvae move in the soil, locate root tips and initiate a new cycle of infection. We have previously demonstrated that the synthetic 24-hydroxy-4-cholen-3-one (C24OH), a dafachronic acid (DA) analogue, is able to control C. elegans life cycle by interfering with the DAF-12 regulated endocrine network (C24OH displays an antagonistic activity). Since C.elegans and parasitic nematodes share the DA system, we decided to test if C24OH has an effect on M.incognita life cycle. Eggs were incubated in presence of increasing concentrations of C24OH and significant differences were observed in the hatching at 96 h (p< 0,0001) between 100 and 200 µM C24OH treated ones compared to the control. In addition, a significant dose response effect of C24OH in M. incognita J2 mortality was observed. After 48 h incubation 16, 28 and 53% of dead J2 were found in the presence of 50, 100 and 200 µM C24OH respectively, whereas only an 8% of dead J2 were found in the control. The effect of C24OH on M. incognita infection was evaluated in tomato plants. Roots were treated for 48 h with increasing concentrations of C24OH and then infected. C24OH treatment decreased significantly the number of galls/root system in a dose response manner (100 µM C24OH produced a 72% reduction). Moreover, plants presented a general improvement in their growth parameters. Specifically, root and aerial part fresh weight from 100 µM C24OH treated plants were a 150% and 215% higher than those of untreated plants respectively. Altogether, our study supports a novel use of C24OH as a nematicide. Keywords M.incognita, DAF-12, nematicide.