Attraction of the Parasitoid Anagrus nilaparvatae to Rice Volatiles Induced by the Rice Brown Planthopper Nilaparvata lugens

Abstract

Anagrus nilaparvatae, an egg parasitoid of the rice brown planthopper Nilaparvata lugens, was attracted to volatiles released from N. lugens-infested plants, whereas there was no attraction to volatiles from undamaged plants, artificially damaged plants, or volatiles from N. lugens nymphs, female adults, eggs, honeydew, and exuvia. There was no difference in attractiveness between plants infested by N. lugens nymphs or those infested by gravid females. Attraction was correlated with time after infestation and host density; attraction was only evident between 6 and 24 hr after infestation by 10 adult females per plant, but not before or after. Similarly, after 24 hr of infestation, wasps were attracted to plants with 10 to 20 female planthoppers, but not to plants with lower or higher numbers of female planthoppers. The attractive time periods and densities may be correlated with the survival chances of the wasps' offspring, which do not survive if the plants die before the wasps emerge. Wasps were also attracted to undamaged mature leaves of a rice plant when one of the other mature leaves had been infested by 10 N. lugens for 1 d, implying that the volatile cues involved in host location by the parasitoid are systemically released. Collection and analyses of volatiles revealed that 1 d of N. lugens infestation did not result in the emission of new compounds or an increase in the total amount of volatiles, but rather the proportions among the compounds in the blend were altered. The total amounts and proportions of the chemicals were also affected by infestation duration. These changes in volatile profiles might provide the wasps with specific information on host habitat quality and thus could explain the observed behavioral responses of the parasitoid.

Duration and location of attraction to herbivore-damaged plants in the tachinid parasitoid Exorista japonica

“…These results indicate that the level of infestation by host larvae may be an important factor for E. japonica females to locate plants with host larvae feeding. The effect of host larvae density on infestation duration and attraction was demonstrated in the egg parasitoid Anagrus nilaparvatae (Lou et al, 2005) and the predatory mite Phytoseiulus persimilis (Gols et al, 2003).…”

The influence of Rosemary plants (Rosmarinus officinalis) volatiles on Aphid (Myzus Persicae)

“…This illuminated the Y-tube with a light intensity of 865 lx. For each of the bioassays, 50 adult aphids were tested following established protocols [18] . The aphids were introduced individually into the entry arm.…”

Protein Baits, Volatile Compounds and Irradiation Influence the Expression Profiles of Odorantbinding Protein Genes in Bactrocera Dorsalis (Diptera: Tephritidae)

“…Previously, thirty-four compounds were selected to investigate the interaction of OBPs with rice plant volatiles (Lou et al, 2005;Sun et al, 2013b). Cnaphalocrocis medinalis OBP2 (CmedOBP2) showed a significant response to host volatiles, whereas CmedOBP3 showed relatively little response to these volatiles (Sun et al, 2016b); our study found that all BdorOBP genes showed low or no response to combined volatile treatments at all tested physiological stages, except the OBP2, OBP5 and OBP1 genes, which were highly expressed.…”