Screening and Identification of Tobacco Mutants Resistant to Potato Virus Y( PVY)

[ Objective] This study aimed to screen and identify tobacco mutants resistant to potato virus Y （PVY）, thus laying the foundation for obtaining PVY resistance genes. [ Method ] At seedling stage, tobacco mutant materials were inoculated with PVY virus and preliminarily screened by naked-eye observation. Enzyme-linked immunosorbent assay （ELISA）, real-time fluorescence quantitative PCR and test strip assay were performed to further identify the pre-screened PVY- resistant seedlings. [ Result ] In 2011, two highly PVY-resistant tobacco mutants （MZE2-15 and MZE2-16） and three PVY-tolerant mutants （MZE2-70, MZE2- 207 and MZE2-228） were obtained, which were further screened and identified in 2012. According to the results, tobacco mutant materials MZE2-407 and MZE2- 428 were susceptible to PVY; mutant materials MZE2-16 and MZE2-15 were resistant to PVY. [ Conclusion] This study provide theoretical basis for the control of tobacco PVY disease.

Tuneable red,green,and blue single-mode lasing in heterogeneously coupled organic spherical microcavities

Tuneable microlasers that span the full visible spectrum,particularly red,green,and blue(RGB)colors,are of crucial importance for various optical devices.However,RGB microlasers usually operate in multimode because the mode selection strategy cannot be applied to the entire visible spectrum simultaneously,which has severely restricted their applications in on-chip optical processing and communication.Here,an approach for the generation of tuneable multicolor single-mode lasers in heterogeneously coupled microresonators composed of distinct spherical microcavities is proposed.With each microcavity serving as both a whispering-gallery-mode(WGM)resonator and a modulator for the other microcavities,a single-mode laser has been achieved.The colors of the single-mode lasers can be freely designed by changing the optical gain in coupled cavities owing to the flexibility of the organic materials.Benefiting from the excellent compatibility,distinct color-emissive microspheres can be integrated to form a heterogeneously coupled system,where tuneable RGB single-mode lasing is realized owing to the capability for optical coupling between multiple resonators.Our findings provide a comprehensive understanding of the lasing modulation that might lead to innovation in structure designs for photonic integration.

An Optically Reconfigurable Förster Resonance Energy Transfer Process for Broadband Switchable Organic Single-Mode Microlasers

Miniaturized lasers with multicolor output and high spectral purity are indispensable for various ultracompact photonic devices.Here,we propose an optically reconfigurable Förster resonance energy transfer(FRET)process to realize broadband switchable single-mode lasing based on in situ activation of acceptors.The stoichiometric ratio of the donor and acceptor in the ready-made microstructures could be modulated readily by precisely activating the acceptors through a photoisomerization process,leading to a reconstructed FRET process to achieve dynamically switchable lasing.Furthermore,dual-color switchable single-mode lasing was realized by selectively constructing the FRET process in an identical coupled microdisks system.These results advance a comprehensive understanding of excited-state dynamics in organic composite material systems,thereby providing new ideas for the rational design of miniaturized photonic materials and devices with desired performances.