Essential oils have insecticidal activity against several insects and are composed of numerous compounds. This study investigated the insecticidal effects of the Thuja occidentalis L. (Cupressaceae) essential oil, terpinyl acetate, and bornyl acetate against the peach aphid [Myzus persicae (Sulzer)]. The insecticidal effect of essential oils on three Cupressaceae plants was highest in T. occidentalis. The Thuja occidentalis essential oil was extracted by steam distillation, and the optimum conditions were found. The GC-MS profiling of essential oil components extracted from T. occidentalis leaves identified 16 volatile compounds. The main components were α-thujone (16.58%), β-myrcene (14.62%), bornyl acetate (9.31%), and terpinyl acetate (8.52%). As a result of the metabolite profiling of three Cupressaceae plants, terpinyl acetate and bornyl acetate were present in large amounts in all of the essential oils, and they had an acetate structure, so it was estimated that they had insecticidal activity. The insecticidal activity of these two compounds was stronger than the other individual monoterpene compounds. The addition of surfactants to the terpinyl acetate and bornyl acetate showed strong insecticidal activity. Terpinyl acetate and bornyl acetate can be used as environmentally friendly insecticidal-active compounds.

The amount of irrigation and fertilization should be considered first for the production and standardization of high-quality H. syriacus L. seedlings using container seedlings. This study was conducted to investigate the optimal conditions suitable for container cultivation of hibiscus by analyzing growth and physiological responses according to the control of irrigation and fertilization. Therefore, in this study, H. syriacus L. for. Haeoreum (3-year-old hardwood cutting propagation), a fast-growing, was transplanted into a 40 L container. The irrigation amount per container was adjusted (0.2, 0.3 and 0.4 ton/yr/tree), and the amount of fertilizer applied (0, 69.0, 138.0 and 207.0 g/yr/tree). The growth rate according to the irrigation-fertilization treatment was higher in the 0.3 ton-138.0 g/yr/tree irrigation-fertilization treatment (p < 0.001). Total biomass yield and seedling quality index (SQI) were highest in the 0.3 ton-138.0 g/yr/tree irrigation-fertilization treatment (p < 0.001). The higher the fertilization concentration, the faster the flowering and the longer the flowering. The photosynthetic capacity of H. syriacus L. was reduced in bare root seedling cultivation and container-non-fertilized treatment. The chlorophyll fluorescence response was also affected by bare root cultivation and containerized seedling cultivation fertilization. Nutrient vector diagnosis showed “nutritional suitability” in the 0.3 ton-138.0 g/yr/tree treatment. Overall, containerized seedling cultivation was superior in growth, photosynthetic performance, photochemical efficiency, and nutrient storage capacity compared to bare root cultivation. These results be expected to contribute not only to the industrial production of excellent container seedlings of H. syriacus L. but also to the production of other woody plants.

Although Liliaceae are valuable resource plants with medicinal and edible uses, techniques for evaluating their tolerance to various abiotic stresses are very limited. This study evaluated the cold tolerance using visual inspection, electrolyte leakage, and Evan’s blue assay. Visual inspection of the responses to different temperatures, using a temperature range of 4 to −12 °C, showed that Scilla scilloides was receive the least damage. However, electrolyte leakage tests showed slightly different results from visual inspection. The median lethal temperature (LT50) was expected to be between −4 and −8 °C. The LT50 was considered a measure of damage due to electrolyte leakage in plant cold tolerance evaluation. As a result of predicting the lethal temperature using the logistic regression equation, the average LT50 of the four plants was −9.0 °C. The species with the lowest LT50 was measured for Hosta plantagines (−11.14°C), whereas the highest LT50 was measured for Hemerocallis fulva (−7.14°C). As a result of the Evan’s blue assay, it was found that cell necrosis occurred when the plants were exposed to low temperatures. Visual observation showed that more than 50% of the three plants’ cells, except for H. plantaginea, were stained blue even at 8 °C. From this result, H. plantaginea was judged to have strong low-temperature tolerance. At −12 °C, more than 50% of the four Liliaceae plants were colored blue, and the LT50 value was expected to be below −12 °C. The reducing sugar content, an indicator of plant cold tolerance, was the highest in H. plantaginea, followed by S. scilloide and H. longipes. Combining the three methods, H. plantaginea had the highest cold tolerance, followed by H. longipes, S. scilloides, and H. fulva. The results of this study will be widely used in selecting cold-tolerant useful resource plants.