Maternally transmitted Wolbachia, Spiroplasma, and Cardinium bacteria are common in insects [1], but their interspecific spread is poorly understood. Endosymbionts can spread rapidly within host species by manipulating host reproduction, as typified by the global spread of wRi Wolbachia observed in Drosophila simulans [2, 3]. However, because Wolbachia cannot survive outside host cells, spread between distantly related host species requires horizontal transfers that are presumably rare [4-7]. Here, we document spread of wRi-like Wolbachia among eight highly diverged Drosophila hosts (10-50 million years) over only about 14,000 years (5,000-27,000). Comparing 110 wRi-like genomes, we find ≤0.02% divergence from the wRi variant that spread rapidly through California populations of D. simulans. The hosts include both globally invasive species (D. simulans, D. suzukii, and D. ananassae) and narrowly distributed Australian endemics (D. anomalata and D. pandora) [8]. Phylogenetic analyses that include mtDNA genomes indicate introgressive transfer of wRi-like Wolbachia between closely related species D. ananassae, D. anomalata, and D. pandora but no horizontal transmission within species. Our analyses suggest D. ananassae as the Wolbachia source for the recent wRi invasion of D. simulans and D. suzukii as the source of Wolbachia in its sister species D. subpulchrella. Although six of these wRi-like variants cause strong cytoplasmic incompatibility, two cause no detectable reproductive effects, indicating that pervasive mutualistic effects [9, 10] complement the reproductive manipulations for which Wolbachia are best known. "Super spreader" variants like wRi may be particularly useful for controlling insect pests and vector-borne diseases with Wolbachia transinfections [11].

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) also known as spotted-wing drosophila (SWD), is a pest native to Southeast Asia. In the last few decades, the pest has expanded its range to affect all major European and American fruit production regions. SWD is a highly adaptive insect that is able to disperse, survive, and flourish under a range of environmental conditions. Infestation by SWD generates both direct and indirect economic impacts through yield losses, shorter shelf life of infested fruit, and increased production costs. Fresh markets, frozen berries, and fruit export programs have been impacted by the pest due to zero tolerance for fruit infestation. As SWD control programs rely heavily on insecticides, exceedance of maximum residue levels (MRLs) has also resulted in crop rejections. The economic impact of SWD has been particularly severe for organic operations, mainly due to the limited availability of effective insecticides. Integrated pest management (IPM) of SWD could significantly reduce chemical inputs but would require substantial changes to horticultural management practices. This review evaluates the most promising methods studied as part of an IPM strategy against SWD across the world. For each of the considered techniques, the effectiveness, impact, sustainability, and stage of development are discussed.

Most animals including insects rely on olfaction to find their mating partners. In moths, males are attracted by female-produced sex pheromones inducing stereotyped sexual behavior. The behaviorally relevant olfactory information is processed in the primary olfactory centre, the antennal lobe (AL). Evidence is now accumulating that modulation of sex-linked behavioral output occurs through neuronal plasticity via the action of hormones and/or catecholamines. A G-protein-coupled receptor (GPCR) binding to 20-hydroxyecdysone, the main insect steroid hormone, and dopamine, has been identified in Drosophila (DmDopEcR), and was suggested to modulate neuronal signaling. In the male moth Agrotis ipsilon, the behavioral and central nervous responses to pheromone are age-dependent. To further unveil the mechanisms of this olfactory plasticity, we searched for DopEcR and tested its potential role in the behavioral response to sex pheromone in A. ipsilon males. Our results show that A. ipsilon DopEcR (named AipsDopEcR) is predominantly expressed in the nervous system. The corresponding protein was detected immunohistochemically in the ALs and higher brain centers including the mushroom bodies. Moreover, AipsDopEcR expression increased with age. Using a strategy of RNA interference, we also show that silencing of AipsDopEcR inhibited the behavioral response to sex pheromone in wind tunnel experiments. Altogether our results indicate that this GPCR is involved in the expression of sexual behavior in the male moth, probably by modulating the central nervous processing of sex pheromone through the action of one or both of its ligands.

Organisms possess photoperiodic timing mechanisms to detect variations in day length and temperature as the seasons progress. The nature of the molecular mechanisms interpreting and signaling these environmental changes to elicit downstream neuroendocrine and physiological responses are just starting to emerge. Here, we demonstrate that, inDrosophila melanogaster, EYES ABSENT (EYA) acts as a seasonal sensor by interpreting photoperiodic and temperature changes to trigger appropriate physiological responses. We observed that tissue-specific genetic manipulation ofeyaexpression is sufficient to disrupt the ability of flies to sense seasonal cues, thereby altering the extent of female reproductive dormancy. Specifically, we observed that EYA proteins, which peak at night in short photoperiod and accumulate at higher levels in the cold, promote reproductive dormancy in femaleD. melanogaster. Furthermore, we provide evidence indicating that the role of EYA in photoperiodism and temperature sensing is aided by the stabilizing action of the light-sensitive circadian clock protein TIMELESS (TIM). We postulate that increased stability and level of TIM at night under short photoperiod together with the production of cold-induced and light-insensitive TIM isoforms facilitate EYA accumulation in winter conditions. This is supported by our observations thattimnull mutants exhibit reduced incidence of reproductive dormancy in simulated winter conditions, while flies overexpressingtimshow an increased incidence of reproductive dormancy even in long photoperiod.