Behavioral and antennal responses of Lobesia botrana (Lepidoptera: Tortricidae) to volatiles from the non-host plant Schinus molle L. (Anacardiaceae)

Abstract

Lobesia botrana (Lepidoptera: Tortricidae), the grapevine moth, is one of the major pest on grapes. Current control is based on spraying insecticides and/or mating disruption technique, using female sex pheromone, affecting only adult male's conduct. Behavioral active compounds as plants kairomones influence the interaction of phytophagous insects with plants, providing chemical cues to feed or lay eggs. Through electroantennography (EAG) and olfactory experiments, we investigated the role of volatiles of the non-host plant Schinus molle L. on behavior of L. botrana. Steam distilled essential oil (EO) from S. molle leaves was characterized by gas chromatography coupled to mass spectrometry (GC-MS). The most abundant compounds were limonene (17.61%), α-phellandrene (14.32%), β-caryophyllene (8.82%) and δ-cadinene (9.39%). Electrical responses of L. botrana at 1×10 2 μg mL-1 EO were not different from control for females (0.81 mV) and males (1.22 mV). At 1×10 3 and 1×10 4 μg mL-1 EO we found a significant increment for females to 1.28 and 1.57 mV, and 1.28 and 1.69 mV for males, respectively. In tube-Y olfactometer, at 1×10 2 μg mL-1 EO the choice did not differ from the control for females (P = 0.7630) and males (P = 0.4054). Females were attracted to odor source at 1×10 3 μg mL-1 (P = 0.0043) and at 1×10 4 μg mL-1 (P = 0.0011). Males were attracted to the dose of 1×10 3 μg mL-1 (P = 0.0278) and at 1×10 4 μg mL-1 (P = 0.0017). We found that non-host plant volatiles elicited electrophysiological and behavioral responses and that L. botrana can discriminate between doses.

Tracking Short-Range Attraction and Oviposition of European Grapevine Moths Affected by Volatile Organic Compounds in a Four-Chamber Olfactometer

“…In the olfactometer experiments, the dose was adjusted to the same as in our EAG experiments (10 µg/µL), which conforms to other studies with grapevine moths [21,22,24]. Deviating VOC doses may result in changes of the behavioral response of females as observed for L. botrana in Y-olfactometer experiments [54] or oviposition tests in this study.…”

“…Furthermore, moth species such as L. botrana possibly avoid artificial and natural oviposition sites treated with particular VOCs as, e.g., shown by Thiéry et al [55] for the substance methanol or Silva et al [54] for essential oils of the non-host plant Schinus molle L. In this study, some compounds (methyl salicylate, α/β-farnesene and (E)-β-caryophyllene) had a negative effect on egg deposition while presenting no increased ovipositor activity in comparison to solvent. These compounds are probably to a greater extent perceived by antennae rather than other extremities of females as suggested by Maher and Thiéry [27].…”

European grapevine moth, Lobesia botrana Part I: Biology and ecology

“…It has been hypothesised that not only antennal olfactory receptors, but also gustatory sensory structures located on the ovipositor may be involved in this behaviour. In contrast, essential oil extracted from another non-host plant, Schinus molle L. (Anacardiaceae), deters oviposition (Silva et al 2019).…”

Variant A of the Deformed Wings Virus Alters the Olfactory Sensitivity and the Expression of Odorant Binding Proteins on Antennas of Apis mellifera

“…In the summer of 2019, we collected leaves from ornamental specimens of both species in Chillán, Ñuble Region, and Chile and obtained 270 and 365 g from M. piperita and E. globulus, respectively. The leaves were air-dried at room temperature for 48 h and then boiled for 8 h to obtain the essential oil by hydro-distillation using a Clevenger apparatus [38]. After this extraction, we added sodium sulfate anhydrous (Na 2 SO 4 ) to remove water from the samples, after which they were stored at 8 • C in complete darkness.…”