Evaluation of Selected Plant Volatiles as Attractants for the Stick Tea Thrip Dendrothrips minowai in the Laboratory and Tea Plantation

Abstract

The stick tea thrip (Dendrothrips minowai Priesner) is the main pest thrip in tea (Camellia sinensis) plantations in China, and seriously affects the quality and yield of tea. Plant-derived semiochemicals provide an alternative to pheromones as lures and these compounds possess powerful attractiveness. In this study, we selected 20 non-pheromone semiochemicals, including compounds that have been reported to attract other thrips and some volatiles emitted from tea plants as the potential attractant components for D. minowai. In electroantennogram (EAG) assays, 10 synthetic compounds (p-anisaldehyde, 3-methyl butanal, (E)-β-ocimene, farnesene, nonanal, eugenol, (+)-α-pinene, limonene, (−)-α-pinene, and γ-terpinene) elicited significant antennal responses in female D. minowai. In addition, a two-choice H-tube olfactometer bioassay showed that D. minowai displayed significant positive responses to eight compound dilutions (p-anisaldehyde, eugenol, farnesene, methyl benzoate, 3-methyl butanal, (E)-β-ocimene, (−)-α-pinene, and (+)-α-pinene) when compared with the solvent control at both 1 and 2 h. Moreover, γ-terpinene exhibited a significantly deterrent effect on D. minowai. Finally, trap catches of four compounds (p-anisaldehyde, eugenol, farnesene, and 3-methyl butanal, respectively) significantly increase in tea plantations. Among these, the maximum number of D. minowai collected by blue sticky traps baited with p-anisaldehyde was 7.7 times higher than the control. In conclusion, p-anisaldehyde, eugenol, farnesene, and 3-methyl butanal could significantly attract D. minowai in the laboratory and under field conditions, suggesting considerable potential as commercial attractants to control D. minowai populations.

Activity Patterns, Population Dynamics, and Spatial Distribution of the Stick Tea Thrips, Dendrothrips minowai, in Tea Plantations

“…During this stage, volatiles such as beta-ocimene, farnesene, and methyl benzoate have been identified [ 47 ]. According to our previous research, D. minowai is attracted to the above three volatiles [ 17 ]. Thus, the presence of overwintering adult thrips in the lower middle part of the tea plants might stem from their attraction to the volatiles of tea flowers.…”

“…The stick tea thrips, D . minowai has become an increasingly significant pest of tea plants in China in recent years [ 16 , 17 ]. D. minowai induces direct damage to tea plants by sucking nutrients from the leaflets; whether it can also be a vector of viruses remains unknown.…”

Aggregation pheromones released by nymphs of the stick tea thrips (Dendrothrips minowai): identification and analysis of their potential utility for controlling thrips in tea plantations

“…To determine the effects of D. minowai volatiles, the behavioral responses of D. minowai adults to volatiles secreted by nymphs, females, and males were tested using modi ed glass H-tube olfactometers (Xiu et al, 2022). To prevent thrips from escaping, both ends of the transverse tube connected to the two straight tubes were sealed with gauze (200 mesh).…”

“…The sticky traps containing different lures were randomly assigned to different parts of the tea garden. Before the trapping trials, sticky traps without any lures were placed in the tea garden for 3 days to con rm that the thrips populations were uniformly distributed in the different treatment areas (Cai et al 2017;Xiu et al 2022). The number of D. minowai adults on the sticky traps was recorded every 3 days, after which the sticky traps were replaced, with the rubber septa attached to the new sticky traps.…”

“…The stick tea thrips (Dendrothrips minowai) is the main pest infesting tea (Camellia sinensis) plantations in China (Lyu et al, 2016;Li et al, 2020). There has recently been an increase in the occurrence of D. minowai infestations, with annual increases in the severity of the associated damage, which has resulted in serious crop losses (Luo et al, 2022;Xiu et al, 2022). However, current methods for controlling this thrips mainly rely on pesticide applications, which can seriously decrease tea quality and safety (Tewary et al, 2005;Ye et al, 2014;Nakai & Lacey, 2017).…”