Biochar is suggested as a conditioner for salt-affected soils for various crops. This study aimed to evaluate the effects of biochar on the growth and physiology of sugarcane under saline and non-saline conditions at an early growth stage. The experiment was conducted in pots in the greenhouses with three replications. Three biochar rates (0, 5, and 10 tons ha⁻¹) were applied before transplanting sugarcane seedlings into the pots. Four weeks after transplanting, plants were irrigated with 300 mL of 100 mM NaCl every two days for 2 weeks. Salinity significantly affected the growth and physiology of sugarcanes. The application of biochar increased plant height, shoot dry weight, root volume, root dry weight, Fv/Fm, and chlorophyll content while decreasing the water saturation deficit and the relative ion leakage in the leaves under both saline and non-saline conditions. Thus, biochar application has positive effects on the growth and physiology of sugarcane at an early growth stage under both saline and non-saline conditions. However, further study is suggested to investigate the effects of biochar on sugarcane under saline stress in the field at different growth stages.

The aim of this study was to investigate the effects of green light, added with red and blue LEDs, on the growth, leaf microstructure and quality of spinach plants. Plants were transplanted and grown hydroponically for 30 days under different combinations of red:blue with a 4:1 ratio (R4B1), red:blue:green with a 5:2:3 ratio (R5B2G3) and red:blue:green with a 1:1:1 ratio (R1B1G1), at a 190 µmoL m⁻²·s⁻¹ photosynthetic photon flux density (PPFD). The results showed that green light, added to red and blue LEDs at a reasonable ratio, could reduce the growth, leaf microstructure and quality of spinach plants, but not the organic acid content. The highest values for the growth parameters, photosynthetic pigments, leaf structure characteristics and quality of the spinach plant were observed for the R4B1 treatment, but not for the organic acid content. Therefore, our results suggest that green light added to red and blue LEDs at a reasonable ratio is not suitable for the growth of spinach.

In this study, an experiment was conducted to suggest optimal daytime temperature and light intensity for cucumber scion and rootstock production in a plant factory with artificial light. Plant growth of cucumber scions and rootstocks at a day/night temperature of 26/18 °C and photosynthetic photon fluxes of 50, 120, 190, 260, 330, and 400 μmol·m⁻²·s⁻¹ was investigated. Plant growth under daytime temperatures of 25/18, 26/18, 27/18, and 28/18 °C at a photosynthetic photon flux of 260 μmol·m⁻²·s⁻¹ was investigated. As the photosynthetic photon flux increased, hypocotyl length was shortened in cucumber scions and rootstocks, but Dickson quality index, compactness, and Seedling Health Index were improved. As the daytime temperature increased, the hypocotyl length of cucumber scions increased, but the quality of seedlings decreased. The root growth of scions decreased as the daytime temperature increased. As for the correlation between the major growth indicators, Dickson quality index, compactness, and Seedling Health Index showed a high correlation of more than 0.8 in stem diameter, leaf, and root weight. Therefore, it is judged that it is most efficient to maintain the photosynthetic photon flux at 260 μmol·m⁻²·s⁻¹ throughout the year and adjust the daytime temperature to 25 to 28 °C according to the season for farms and commercial nurseries that produce cucumber seedlings by installing plant factories with artificial light.

This study was conducted to evaluate the salt tolerance ability of two soybean cultivars under salinity conditions using a selection of growth and physiological parameters. Three weeks after germination, plants began being treated with either a 100 mM concentration of NaCl in Hoagland solution or a non-salinity (0 mM NaCl) solution. The results showed that the plant height, number of leaves, leaf area index, and shoot and root biomasses were significantly reduced under salt conditions. A similar tendency was observed in several physiological parameters (SPAD, Fv/Fm). Since all the salt-treated plants of the D8 cultivar were dead after 40 days under the 100 mM NaCl treatment, the yield of D8 could not be obtained, while the treated plants of the D140 cultivar experienced a marked decrease in yield compared to the control plants. In this study, we identified that the D140 soybean cultivar had a better salt tolerance than the D8 soybean cultivar at a 100 mM NaCl concentration.

Ehretia asperula’s physiological responses to growth performance following oak-wood biochar application under water stress conditions (WSC) and no water stress conditions (non-WSC) were investigated in a pot experiment. Biochar (WB) was incorporated into the soil at concentrations of 0, 5, 10, 15, and 20 tons ha⁻¹ before transplanting Ehretia asperula in the pots. One month after transplanting, Ehretia asperula plants were put under water stress by withholding water for ten days. Water stress significantly decreased the growth and physiology of Ehretia asperula. Under WSC, the application of WB at the concentrations of 15 and 20 tons ha⁻¹ to the soil increased the plant height; number of leaves; fresh and dry weight of the roots, shoots, and leaves; F_v/F_m; chlorophyll content; leaf relative water content; and soil moisture as well as decreased the relative ion leakage. The application of WB enhanced drought tolerance in Ehretia asperula plants by lowering the wilting point. The findings suggest that WB application at the concentration of 15 tons ha⁻¹ could be recommended for ensuring the best physiological responses and highest growth of Ehretia asperula plants.