Nematicidal effect of volatile organic compounds (VOCs) on the plant-parasitic nematode Meloidogyne javanica

Abstract

Estudos anteriores demonstraram que compostos orgânicos voláteis (COVs), produzidos pela levedura Saccharomyces cerevisiae, são capazes de inibir o desenvolvimento de fungos fitopatogênicos. Neste contexto, foi avaliado o potencial nematicida da mistura sintética de COVs, constituída por alcoóis e ésteres, para o controle do nematóide das galhas Meloidogyne javanica, que causa perdas em The javanese root-knot nematode Meloidogyne javanica is a major plant pathogen widespread in the tropics. As the management of M. javanica by traditional methods is laborious and infested areas frequently become not viable for agricultural use, the development of new control methods is desirable. RESUMOIn previous studies, VOCs produced by the yeast Saccharomyces cerevisiae, or their artificial mixtures, inhibited several phytopathogenic fungi (1, 2). The effect of VOCs on plant parasitic nematodes is scarcely studied. Thus, an in vitro assay was carried out in order to evaluate the effect of an artificial mixture of VOCs, identified from the yeast, on the survival of M. javanica juveniles.The artificial mixture of VOCs was prepared by using standard chemicals (Sigma-Aldrich), based on the results of the analysis of gaseous atmosphere produced by S. cerevisiae (1). The analysis was carried out by Fialho et al. (1) by using gas chromatography with mass spectrometric detection (GC-MS). The concentration of each compound present in the mixture was based on its relative proportion (%), estimated by the area in relation to all other components of the mixture (Table 1). The population of M. javanica was maintained in soybean plants in a greenhouse. M. javanica egg masses were stained by immersing the roots in phloxine B solution (0.0015%) for 20 min. Then, the egg masses were hand-picked, transferred to hatching chambers and maintained at 30 °C (4). A suspension of second stage juveniles (J2) of the nematode was obtained after 24h and used as inoculum. Commercially available polystyrene plates (60 mL volume) divided in half by a wall were used for the assay. On one side of the plate, a total of 2.3 mL of the suspension containing 1,000 juveniles (J2) was added to 1.5 g of the substrate vermiculite. On the opposite

Bioactive Volatiles from an Endophytic Daldinia cf. concentrica Isolate Affect the Viability of the Plant Parasitic Nematode Meloidogyne javanica

“…incognita [42]. Although the effect of each individual component was not determined in those studies [42, 43], our present results confirm their nematicidical activity (Fig 3). However, the effect of the third component, isoamyl acetate, depended on the nematode: although it was a potent attractant for C .…”

“…Among the four chemical components of our SVM, three are already correlated with plant parasitic nematode activity: 2-methyl-1-butanol [43] and 3-methyl-1-butanol [42, 43] were ingredients of SVM that exhibited nematicidal effects against M . javanica [43] and M .…”

“…Nematicidal VOCs were observed in the model yeast Saccharomyces cerevisiae : exposure of second-stage juveniles of M . javanica to a synthetic mixture of the yeast VOCs resulted in nematode mortality [43]. Similarly, VOCs produced by Fusarium oxysporum isolated from rhizospheres of coffee plants were nematicidal against M .…”

Identification and Characterization of Nematicidal Volatile Organic Compounds from Deep-Sea Virgibacillus dokdonensis MCCC 1A00493

“…Each VOC produced by MCCC 1A00493 has different effects on RKNs. Multiple VOCs can be used to simultaneously control RKNs [43,44]. The mixture of VOCs produced by bacteria may be more effective to control nematodes than treatment with synthetic nematicides composed of a single compound [44].…”

Wood-associated fungi produce volatile organic compounds toxic to root-knot nematode

“…According to the authors, an artificial mixture of VOCs with the compounds 3-methyl-1-butanol and 2-methyl-1-butanol was able to fully suppress the development of G. citricicarpa. Fialho et al (2012) also performed fumigation on a substrate containing second-stage juveniles with a mixture of synthesized VOCs including the molecules cited above. The nematicide effect was over 30 % with the lowest substrate concentration (33.3 mL g −1 ), and with 66.6 and 133.3 mL g −1 of the substrate, the nematode mortality was 100 %.…”