수온 및 조도에 따른 뜸부기（Silvetia siliquosa） 유배의 생장특성 및 초기 발달 = Growth Characteristics and Early Development of Silvetia siliquosa Embryos under Different Water Temperature and Light Conditions

다국어 초록 (Multilingual Abstract)

This study examined the early development of the brown alga Silvetia siliquosa and evaluated embryo growth under different water temperature and light condition in laboratory culture. Mature thalli bearing reproductive receptacles were collected from the intertidal zone of Jindo, Korea. Gamete release was induced under controlled conditions, and the resulting zygotes were allowed to settle naturally onto glass slides. Each treatment consisted of three replicate dishes, and the mean of 10 randomly selected embryos per dish was used as the statistical unit. The resulting zygotes were spherical to oval immediately after fertilization. Polarity was established within approximately 12 h, followed by asymmetric cell division and differentiation into rhizoid and apical cells within 24 h. Rhizoid elongation and branching were observed from 48 h after fertilization, indicating the progression of early morphological development. To evaluate the effects of water temperature, embryos were cultured at 10, 15, 20, 25, and 30 °C under 5,000 lx for up to 90 days. Total length, apical diameter, apical length, and rhizoid length generally increased with culture duration, although their growth patterns differed among the temperature treatments. At Day 90, the 20 °C treatment showed generally high values for all measured growth characteristics. Relative growth rates differed significantly among the temperature treatments for total length （Welch’s F = 44.589, p = 0.001）, apical diameter （F = 27.492, p 〈 0.001）, apical length （F=63.614, p 〈 0.001）, and rhizoid length （F = 35.132, p 〈 0.001）. Among the treatments examined, the relative growth rates were generally high at 20 °C. In contrast, embryos in the 30 °C treatment showed comparatively low growth, and culture was discontinued after Day 30. To evaluate the effects of light condition, embryos were cultured at 2,500 and 5,000 lx at 20 °C for 30 days. At Day 30, total length, apical length, and rhizoid length were significantly greater in the 5,000 lx treatment than in the 2,500 lx treatment, whereas apical diameter did not differ significantly between the two treatments. The relative growth rates of total length and apical length were also significantly higher in the 5,000 lx treatment （p = 0.026, p = 0.003, respectively）. In contrast, the relative growth rates of apical diameter and rhizoid length did not differ significantly between the light treatments （p = 0.371, p = 0.289, respectively）. These results indicate that the early growth of S. siliquosa embryos varied among the water temperature and light condition. Among the treatments examined, embryo growth was generally greater at 20 °C and 5,000 lx. However, because only two light levels were examined using illuminance measured in lux, the 5,000 lx treatment should not be interpreted as the absolute optimum light condition. This study provides quantitative information on the early development and culture responses of S. siliquosa embryos and may serve as a basis for refining seedling production protocols and evaluating their potential application to conservation and restoration programs.

목차 (Table of Contents)

• Ⅰ. 서 론 1
• Ⅱ. 재료 및 방법 3
• 1. 조사해역 및 채집지 3
• 2. 접합자의 확보 및 초기발달 5
• 3. 수온 및 조도 조건별 배양 7
• 4. 유배의 생장 측정 및 통계 분석 9
• Ⅲ. 결 과 11
• 1. 접합자의 초기 발달 11
• 2. 수온에 따른 유배의 생장 12
• 3. 조도에 따른 유배의 생장 25
• Ⅳ. 고 찰 34
• Ⅴ. 결 론 37
• Ⅵ. 참고문헌 39
• Ⅶ. 부 록 43