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The 2010 Deepwater Horizon oil spill injured mesophotic and deep-sea environments over a vast area. In order to restore mesophotic and deep-sea coral species impacted by the spill, information on fundamental ecosystem processes such as reproduction is needed. During expeditions in 2021 and 2022, fragments of the mesophotic octocoral Swiftia exserta were collected from the northern Gulf of Mexico and transported to aquaria at federal facilities in South Carolina, Florida, and Texas. In fall of 2021 and 2022, several of these fragments spawned in captivity, providing an opportunity to learn about their reproduction and inform future restoration activities. Broadcast spawning occurred on 19 and 20 October, 2021, and on 20 days from 29 September to 7 November, 2022. These spawning events permitted detailed observations of spawning behavior and timing, and yielded over 2,400 oocytes. Individual spawns were preceded by a distinctive "spawning posture" in the polyps, lasting between five minutes and two hours, and may have been cued by light. Swiftia exserta larvae settled and developed at comparable rates to other broadcast spawning octocorals, becoming swimming planulae by three days post spawn (dps) and starting to settle by 14 dps. These observations represent the first such records for S. exserta and, more broadly, for any mesophotic coral in the Gulf of Mexico, providing important insights for the restoration of these species. This investigation lays the foundation for future work to explore the influences of seasonal environmental variables, such as light and temperature, on spawning and reproductive seasonality in this species. [ABSTRACT FROM AUTHOR]

In this study, newly identified small molecules were examined for efficacy against 'Candidatus Liberibacter asiaticus' in commercial groves of sweet orange (Citrus sinensis) and white grapefruit (Citrus paradisi) trees. We used benzbromarone and/or tolfenamic acid delivered by trunk injection. We evaluated safety and efficacy parameters by performing RNAseq of the citrus host responses, 16S rRNA gene sequencing to characterize citrus-associated microbial communities during treatment, and qRT-PCR as an indirect determination of 'Ca. L. asiaticus' viability. Analyses of the C. sinensis transcriptome indicated that each treatment consistently induced genes associated with normal metabolism and growth, without compromising tree viability or negatively affecting the indigenous citrus-associated microbiota. It was found that treatment-associated reduction in 'Ca. L. asiaticus' was positively correlated with the proliferation of several core taxa related with citrus health. No symptoms of phytotoxicity were observed in any of the treated trees. Trials were also performed in commercial groves to examine the effect of each treatment on fruit productivity, juice quality and efficacy against 'Ca. L. asiaticus'. Increased fruit production (15%) was observed in C. paradisi following twelve months of treatment with benzbromarone and tolfenamic acid. These results were positively correlated with decreased 'Ca. L. asiaticus' transcriptional activity in root samples. [ABSTRACT FROM AUTHOR]