Photoautotrophic growth response of in vitro cultured coffee plantlets to ventilation methods and photosynthetic photon fluxes under carbon dioxide enriched condition

Effects of two ventilation methods (forced and natural) and two photosynthetic photon fluxes (PPF, 150 and 250 μmol m⁻² s⁻¹) on the photoautotrophic growth of in vitro cultured coffee (Coffea arabusta) plantlets were investigated. Number of air exchanges was 2.7, 5.9 and 3.9 h⁻¹ for forced low rate, forced high rate and natural ventilation, respectively. Single node cuttings of in vitro cultured coffee plantlets were cultured on Florialite, a mixture of vermiculite and cellulose fibers with high air porosity, emerged in liquid half strength basal MS medium, without sucrose, vitamins and plant growth regulators. The study included 40 days in the in vitro stage and 10 days in the ex vitro stage. Mean fresh and dry weights, leaf area, shoot and root lengths and net photosynthetic rate per plantlet were significantly greater in forced high rate treatments compared with those in natural and forced low rate treatments. PPF had a distinct effect on shoot length suppression and root elongation of coffee plantlets in forced high rate treatments. The control of carbon dioxide concentration inside the culture box according to the plant demand when growing was easy with the forced ventilation method in photoautotrophic micropropagation. This revised version was published online in June 2006 with corrections to the Cover Date.     

Comparing Protein Expression in Erwinia amylovora Strain TS3128 Cultured under Three Sets of Environmental Conditions

Erwinia amylovora, the causal agent of fire-blight disease in apple and pear trees, was first isolated in South Korea in 2015. Although numerous studies, including omics analyses, have been conducted on other strains of E. amylovora, studies on South Korean isolates remain limited. In this study, we conducted a comparative proteomic analysis of the strain TS3128, cultured in three media representing different growth conditions. Proteins related to virulence, type III secretion system, and amylovoran production, were more abundant under minimal conditions than in rich conditions. Additionally, various proteins associated with energy production, carbohydrate metabolism, cell wall/membrane/envelope biogenesis, and ion uptake were identified under minimal conditions. The strain TS3128 expresses these proteins to survive in harsh environments. These findings contribute to understanding the cellular mechanisms driving its adaptations to different environmental conditions and provide proteome profiles as reference for future studies on the virulence and adaptation mechanisms of South Korean strains.     

Growth responses of marigold and salvia bedding plants as affected by monochromic or mixture radiation provided by a Light-Emitting Diode (LED)

The effects of light generated by monochromic blue, red or mixed radiation from a fluorescent lamp (FL) with light emitting diodes (LEDs) (blue, red, or far-red) on growth and morphogenesis of marigold and salvia seedlings were investigated and the responses compared with those of plantlets grown under a broad spectrum conventional fluorescent lamp (a 16 h photoperiod per day). Dry weight of marigold seedlings was significantly increased in monochromic red light (R), fluorescent light plus red LED (FLR) or fluorescent light (FL) but reduced when monochromic blue light (B) was used, whereas in salvia dry weight was significantly greater under fluorescent light plus blue LED (FLB), fluorescent light plus red LED (FLR) and fluorescent light plus far-red LED (FLFr) as compared to other treatments. Stem length in marigold was greatest in monochromic blue light, being three times greater than in FLR or FL treatments. In salvia, FLFr increased stem length but this was significantly decreased by R as compared to other treatments. The number of visible flower buds in marigold was much higher in FLR as well as in the control (FL), and it was about five times greater than in B or R. However, the number of open flowers in salvia varied slightly in all the treatments. Different light qualities also influenced the duration of the blooming period in both the species. No flower buds were formed when monochromic B or R was used in salvia and FLFr inhibited flower bud formation in marigold. In comparison with monochromic blue or red light, the number of stomata was greater in mixed radiation of FL with LEDs in both the plants. Our study demonstrates the effectiveness of a LED system for plantlet growth and morphogenesis in space-based plant research chambers.