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Host-induced gene silencing (HIGS) is a common method for engineering plant protection against pathogens, although success requires double-stranded RNA (dsRNA) uptake mechanisms that may not be present in all fungi. We explored HIGS in transgenic poplar to study and control Sphaerulina musiva, the cause of Septoria stem canker disease. HIGS transgenic poplars expressing dsRNA that targeted either or both S. musiva CYP51 and DCL were developed and screened for resistance to stem canker disease in two greenhouse inoculation trials. While differences in resistance between transgenic lines and wild-type controls were not detected, there was a correlation between greenhouse-expressed disease resistance and transgene expression among HIGS lines targeting S. musiva DCL. To evaluate the likelihood that HIGS or spray-induced gene silencing might be effective under some conditions, concurrent with greenhouse screening, we studied: (i)  S. musiva’s capacity for uptake of environmental dsRNA; (ii) effects of in vitro silencing of CYP51 and DCL on fungal growth and target transcript abundance; and (iii) persistence of dsRNA in culture. The uptake of fluorescently tagged dsRNA was not detected with confocal imaging. In dsRNA-treated cultures, fungal growth inhibition was not detected, and RNA was rapidly degraded. Of the five target transcripts tested after dsRNA treatment, only DCL1 had reduced expression. Knockdown of DCL1 along with the enhanced resistance among high-expressing HIGS events targeting DCL suggests some HIGS may have been observed. Further determination of the factors limiting dsRNA uptake by S. musiva are needed to determine whether HIGS can be an effective technology for limiting stem canker. [Formula: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license . 

A new deep-blue emitting and highly fluorescent anthracene (ANTH) derivative containing perfluorobenzyl (Bn_F) groups, 9,10-ANTH(Bn_F)₂, was synthesized in a single step reaction of ANTH or ANTH(Br)₂with Bn_FI, using either a high-temperature Cu-/Na₂S₂O₃-promoted reaction or via a room-temperature photochemical reaction. Its structure was elucidated by NMR spectroscopy and single crystal X-ray diffractometry. The latter revealed no π–π interaction between neighboring ANTH cores. A combination of high photoluminescence quantum yield (PLQY) of 0.85 for 9,10-ANTH(Bn_F)₂, its significantly improved photostability compared to ANTH and 9,10-ANTH derivatives, and a simple synthetic access makes it an attractive material as a deep-blue OLED emitter and an efficient fluorescent probe. 

Hybrid-poplar tree plantations provide a source for biofuel and biomass, but they also increase forest isoprene emissions. The consequences of increased isoprene emissions include higher rates of tropospheric ozone production, increases in the lifetime of methane, and increases in atmospheric aerosol production, all of which affect the global energy budget and/or lead to the degradation of air quality. Using RNA interference (RNAi) to suppress isoprene emission, we show that this trait, which is thought to be required for the tolerance of abiotic stress, is not required for high rates of photosynthesis and woody biomass production in the agroforest plantation environment, even in areas with high levels of climatic stress. Biomass production over 4 y in plantations in Arizona and Oregon was similar among genetic lines that emitted or did not emit significant amounts of isoprene. Lines that had substantially reduced isoprene emission rates also showed decreases in flavonol pigments, which reduce oxidative damage during extremes of abiotic stress, a pattern that would be expected to amplify metabolic dysfunction in the absence of isoprene production in stress-prone climate regimes. However, compensatory increases in the expression of other proteomic components, especially those associated with the production of protective compounds, such as carotenoids and terpenoids, and the fact that most biomass is produced prior to the hottest and driest part of the growing season explain the observed pattern of high biomass production with low isoprene emission. Our results show that it is possible to reduce the deleterious influences of isoprene on the atmosphere, while sustaining woody biomass production in temperate agroforest plantations. 

Abstract Faux‐hawk fullerenes are promising candidates for high‐performance organic field‐effect transistors (OFETs). They show dense molecular packing and high thermal stability. Furthermore, in contrast to most other C₆₀derivates, functionalization of the fullerene core by the fluorinated group C₆F₄CF₂does not increase their lowest unoccupied orbital position, which allows the use of air‐stable molecular n‐dopants to optimize their performance. The influence of n‐doping on the performance of OFETs based on the faux‐hawk fullerene 1,9‐C₆₀(cyclo‐CF₂(2‐C₆F₄)) (C₆₀FHF) is studied. An analytic model for n‐doped transistors is presented and used to clarify the origin of the increase in the subthreshold swing usually observed in doped OFETs. It is shown that the increase in subthreshold swing can be minimized by using a bulk dopant layer at the gate dielectric/C₆₀FHF layer instead of a mixed host:dopant layer. Following an optimization of the OFETs, an average electron mobility of 0.34 cm² V⁻¹ s⁻¹, a subthreshold swing below 400 mV dec⁻¹for doped transistors, and a contact resistance of 10 kΩ cm is obtained, which is among the best performance for fullerene based n‐type semiconductors.