Study on Induction of Phytolacca acinosa Roxb. Polyploids with Colchicine

[ Objective ] This study aimed to obtain Phytolacca acinosa Roxb. polyploids and provide high-efficiency raw materials for the preparation of biological pesticides. [Method] Terminal bud growing points of Phytolacca acinosa Roxb. seedlings were treated with 0.1%, 0.2%, 0.3% colchicine and 1% agar solution for 24, 48 and 72 h, respectively, while Phytolacca acinosa Roxb. without treatment was adopted as the control. The mutagenic effect of various concentrations of colchicine was calculated. Phytolacca acinosa Roxb. mutants were identified using morphological, anatomical and cytological methods. [ Result] Induction with 0. 2% colchicine for 48 h led to the highest mntagenic effect. Compared with the control, leaf width and leaf thickness of mutants were enhanced by 40. 15% and 33. 25%, respectively; vertical and horizontal diameter of stomata of mutants were enhanced by 30.25% and 60.82%, respectively ; the stomata density of mutants was improved by 150%. Identification of meiotic chromosome of pollen mother cells using compression method showed that the chromosome number of microspore cells of Phytolacca acinosa Roxb. mutants was n = 2 x = 36, while that of the control was n = x = 18, indicating that the mutants were tetraploids. [ Conclusion ] Phytolacca acinosa Roxb. polyploids were induced using the traditional liquid droplet method, which was easy and direct with simple operation and good effect to acquire a large number of polyploid materials within a short time.

Unraveling the Effect of Stacking Configurations on Charge Transfer in WS_(2) and Organic Semiconductor Heterojunctions

Photoinduced interfacial charge transfer plays a critical role in energy conversion involving van der Waals(vdW)heterostructures constructed of inorganic nanostructures and organic materials.However,the effect of molecular stacking configurations on charge transfer dynamics is less understood.In this study,we demonstrated the tunability of interfacial charge separation in a type-Ⅱ heterojunction between monolayer(ML)WS_(2) and an organic semiconducting molecule[2-(3″′,4′-dimethyl-[2,2′:5′,2′:5″,2″′-quaterthiophen]-5-yl)ethan-1-ammonium halide(4Tm)]by rational design of relative stacking configurations.The assembly between ML-WS_(2) and the 4Tm molecule forms a face-to-face stacking when 4Tm molecules are in a selfaggregation state.In contrast,a face-to-edge stacking is observed when 4Tm molecule is incorporated into a 2D organic-inorganic hybrid perovskite lattice.The face-to-face stacking was proved to be more favorable for hole transfer from WS_(2) to 4Tm and led to interlayer excitons(IEs)emission.Transient absorption measurements show that the hole transfer occurs on a time scale of 150 fs.On the other hand,the face-to-edge stacking resulted in much slower hole transfer without formation of IEs.This inefficient hole transfer occurs on a similar time scale as A exciton recombination in WS_(2),leading to the formation of negative trions.These investigations offer important fundamental insights into the charge transfer processes at organic−inorganic interfaces.