Effects of Nitrogen Fertilizers and Light on the Morphological and Physiological Changes and Outplanting Performance of Three- cupule Tanoak (Pasania ternaticupula Hay.) Seedlings

• Main Authors: Chen, Shuen-Ying, 陳舜英
• Other Authors: Shing-Rong Kuo, Ching-Te Chien
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/34298663431439097662

碩士 === 國立臺灣大學 === 森林學系 === 85 === This study investigated the changes in the morphology and physiology of Pasania ternaticupula seedlings by treating germinated seedlings continuously with different levels of nitrogen fertilizers and light intensities, and examined the outplanting performance of those nursery seedling stocks. The results showed that height growth, collar diameter, dry weights of shoots and roots, Dickson quality index, the numbers of stomata per unit leaf area and ratio of chlorophyll a and b of seedlings increased when the relative light intensity was increased in the greenhouse. Relative light intensities of 26% and 16% full daylight were more effective than a relative light intensity of 4% full daylight. However, the increases of dry weight of leaf, shoot-root ratio, leaf numbers, leaf area, leaf area ratio, special leaf area and total chlorophyll content in leaf were measured under a relative light intensity of 4% full daylight and were significantly different as compared to a relative light intensity of 26% full daylight. In the nitrogen fertilizer experiment, growth height, collar diameter, dry weight of seedling, leaf numbers, leaf area and ratio of chlorophyll a and b of seedlings were increased following an increase in nitrogen fertilizer quantity. The analysis of 20 amino acids from leaves revealed that there was no significant difference in concentrations of these amino acids among the four nitrogen fertilizer treatments. However, concentrations of each of the 20 amino acids increased when light intensity decreased. According to a correlation analysis, seedling growth after outplanting was affected by both nitrogen fertilizers and light intensities. Furthermore, correlation analysis between seedling growth and parameters indicated that seedling growth was positively correlated with the Dickson quality index, but negatively correlated with special leaf area and tryptophan. In summary, the treatments with relative light intensity of 26% or 16% full daylight, and nitrogen concentrations of 300 or 400kg per ha had better seedling growth.