Appropriate Amount of Nitrogen Fertilizer for Shading Cultivation of Tea Tree Seedlings

Abstract

Nitrogen fertilizers are essential for productivity and quality improvement of all crops. However, excessive nitrogen can cause physiological disturbances. Therefore, depending upon the type of crop and cultivation method, controlling the amount of fertilizer is important. Typically, the proper amount of nitrogen fertilizer is determined by the organic matter content of the soil in which the plants (tea plants in our case) are grown. However, there is no difference in the amount of fertilizer applied during shading which leads to serious problems. The current study investigated the physiological activity of tea plants according to nitrogen concentration in oil cake during shading cultivation. The physiological activity expressed via photosynthetic ability showed that the photosynthetic ability remained steady without being significantly affected by nitrogen content up to 9 to 12% under non-shading conditions, whereas nitrogen excess disorder started to occur as the treatment period increased under shading conditions. After 3 weeks of treatment, the leaf chromaticity was the highest at 67.67 for 4.5% oil cake under shading condition, while the highest was 64.19 for 12% oil cake under the non-shading condition. In terms of inorganic nitrogen content in the soil, the NH 4

An Analysis of the Growth and Photosynthetic Responses of Potted <italic>Veronica pusanensis</italic> Y.N.Lee according to the Shading Levels

“…Chlorophyll fluorescence analysis is one of the methods to identify plant stress levels and the inactivity of the reaction center of photosystem II (PSII), which can be done in the non-destructive investigation (Lechaudel et al, 2010;Shim and Jeon, 2022). Chlorophyll fluorescence analysis that had been applied in various studies in the past had its usefulness proved by being used in assessing the photosynthetic efficiency and stress of plants through various fluorescence parameters such as F v /F m , Φ Do , ABS/RC, DI o /RC, and PI ABS (An et al, 2022;Choi et al, 2022;Kwon et al, 2021;Oh and Lee, 2022;Yang et al, 2022).…”

Comparison of Growth and Leaf Color Quality of <italic>Mesembryanthemum cordifolium</italic> f. <italic>variegata</italic> as Affected by Shading Levels

“…Previous studies were conducted on the growth of succulent plants according to shading levels (Lee et al, 2021b;2022c;Nam et al, 2022), the effect of shading treatment on the growth of ornamental flower crops (Jang et al, 2022;Kwon et al, 2020;Park and Kim, 2021), and adequate shading levels for vegetables and tea tree (Cao et al, 2022;Shim and Jeon, 2022;Sim et al, 2021). As such, studies reported different results for various plant species, and it is also necessary to investigate the most suitable shading level for the cultivation of M. cordifolium f.…”