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Understanding vector dispersal capacity is key to assessing the risk of spread of vector borne pathogens. For flying vectors, flight performance is associated with primary and secondary pathogen spread. However, because pathogens induce changes in vector physiology, pathogen status in the vector may impact vector dispersal. In this work, by using flight mills, we assessed the flight performance of Bactericera cockerelli that were infected or not by the plant pathogenic bacterium 'Candidatus Liberibacter solanacearum' (CLso), the causal agent of potato zebra chip disease and vein greening in tomato. Bactericera cockerelli performed short and long-distance flights, but CLso infection status affected the propensity to engage in long flights. CLso-free insects engaged in long flights significantly more often (57%) compared to CLso infected insects (25%). Average distance dispersed for long flyers was 185.33 m for CLso-free insects and 122.99 m for insects infected with CLso. However, distance dispersed was not statistically different by pathogen status of the vector. Maximal flight capacity recorded was 980 m. Overall, our data suggest that CLso reduces the propensity to engage in long distance flights. Our results can be utilized to fine-tune strategies to mitigate CLso establishment in new areas. [ABSTRACT FROM AUTHOR]

The Asian corn borer, Ostrinia furnacalis, is the most notorious corn pest in East Asia and Oceania. The larvae seriously damage crops and lower yields. A previous study found that the O. furnacalis can migrate seasonally. However, the influencing factor on the flight performance of this pest has not yet been investigated. Here, the flight performance and its influencing factors of O. furnacalis were tested using computer-monitored flight mills. The results showed that the longest total flight of an individual was 71.49 km with a mean speed of 6.36 km·h−1 (1.77 m·s−1). Flight performance reached the peak when the moths were 2-days old, with a mean flight distance of 18.89 ± 2.03 km, mean flight duration of 7.34 ± 0.62 h and mean flight speed of 2.47 ± 0.10 km·h−1 (0.69 m·s−1). The flight capability of females was always higher than that of males. Mating status and nutritional status affected partial flight variables. For both sexes, only temperature and relative humidity among the abiotic factors significantly involved flight performance, which was most significant at 25–30 °C and 55–65%. Our study demonstrated that O. furnacalis have a high capability for migration and determined the influencing factors on flight performance. These results provide essential information for forecasting and management of this pest. [ABSTRACT FROM AUTHOR]

Dopamine (DA), one of the biogenic amines, has been suggested to regulate the motor activities of various animals. In honey bees, it has been reported to promote locomotor activity in queens, workers, and males, and to regulate the flight activity of workers and males. The role of DA in the flight activity of queens, however, has not yet been investigated. In this study, we tested the roles of DA in the flight activity of virgin queens. We first injected the DA receptor antagonist flupenthixol (10−2 M or 10−3 M) into the abdomens of 6-day-old virgin queens and measured the time to flight initiation. The same experiment was performed in workers, to confirm previous findings and compare them to the virgin queens. We then injected 10−2 M flupenthixol into the queens and quantified their flight activity using a flight mill. The workers were deemed unsuitable for this round of experimentation. In both queens and workers, flupenthixol injection significantly delayed flight initiation. In flight mill experiments, flupenthixol decreased the flight performance of the queens in terms of distance, duration, and velocity. These results suggest the involvement of DA in the flight activity of virgin queens and workers, and indicate that DA is a key neuroactive substance in motor system activation with conserved effects among honey bee queens, workers, and males. [ABSTRACT FROM AUTHOR]

The ambrosia beetle Platypus quercivorus (Coleoptera: Platypodidae) is a vector of the pathogenic fungi, Raffaelea quercivora (Ophiostomatales: Ophiostomataceae), which causes Japanese oak wilt disease. Previous studies have shown that the beetle displays positive phototactic behavior; however, the adaptive significance of this behavior remains unclear. We postulated that positive phototaxis is necessary to allow the beetle to fly skyward immediately after emergence from a tree, and that this taxis changes following a certain period of flight. The present study aimed to clarify the changes in phototactic behavior of P. quercivorus before and after flight by using individual beetles emerging from the trunk of a Quercus crispula (Fagales: Fagaceae) tree that was attacked in 2014. The response of 60 beetles to light was tested ten times each, before and after flight in a flight mill. A generalized linear mixed model was constructed to predict the probability of positive phototaxis of P. quercivorus before and after flight. A best-fit model showed that the probability of positive phototaxis was lower after flight than before. The results suggest that positive phototaxis of P. quercivorus is decreased after flight. [ABSTRACT FROM AUTHOR]