Effect of Inorganic Environmental Factors on the Growth of Pinus koraiensis Seedlings (I) - The Influence of Shading on the Growth of Seedlings Grown on the Seed Bed -

무기적(無機的) 환경요인(環境要因)이 잣나무 유묘(幼苗)의 생육(生育)에 미치는 영향(影響)에 관(關)한 연구(硏究)(I) - 파종상(播種床)에 있어서의 피음처리(被陰處理) 영향(影響) -

This study was carried out to investigate the influence of light intensity on the growth of Korean white pine (Pinus koraiensis) seedlings. The seedlings were grown under four different relative light intensities: 100%, 63%, 37%, and 19% of full sunlight by covering with saran screen on seed bed. The results obtained were summarized as follows; 1. The highest shoot elongation was found at 37% in relative light intensity (RLI) plot, and the best growth in root, seedling length and diameter increment appeared at 100% on RLI plot. Contribution rates of shading to growth in shoot elongation, root growth, seedling length, and diameter increment were 9.3%, 26.2%, 21.0%, and 48.7%, respectively. 2. The greatest number of one-year-old needle fascicle was found at 100% in RLI plot, whereas that of two-year-old needle fascicle appeared at 37% in RLI plot. The contribution rate of the light intensity to number of needle fascicle was 3.9% and factor of leaf age contributed to number of needle fascicle in 27.8%. The length of needles grown under different light intensities varied with needle ages. The longest length of new needles appeared at 37% in RLI plot, but old needles were not clear in influence of light intensity. The contribution rate to needle length by the light intensity was 2.5%. 3. The heaviest value of the fresh and dry weight of seedlings appeared at 100% of RLI plot then decreased with light intensity. The contribution rates to fresh and dry weight by the shading were 38% and 7.6% respectively. 4. The largest value of the dry weight of needles appeared at 100% of RLI plot and then decreased with light intensity. The contribution rates to dry weight of needles by the light intensity was 13.18%. 5. The values of T/R ratio increased with decreased light intensity and the contribution rate was 7.0%. 6. Positive correlation and linear regressions were recognized between dry weight of leaf and other factors (dry weight of shoot, root, seedling and diameter increment).

파종상(播種床)에서 피음처리(被陰處理)를 행(行)한 잣나무 유묘(幼苗)의 상대광도별(相對光度別) 생장관계(生長關係)를 분석(分析)하였던 바 기(其) 결과(結果)를 요약(要約)하면 다음과 같다; 1) 신장생장(伸長生長)에 있어서 지상부(地上部)는 상대광도(相對光度) 37% 구(區)에서, 그리고 기외(其外)의 기관(器官)은 100% 구(區)에서 가장 크게 나타났다. 광도(光度)가 지상부(地上部) 및 지하부(地下部), 묘장(苗長), 직경생장(直徑生長)에 미치는 영향(影響)은 기여율(寄與率) 93%, 26.2%, 21.4%. 48.7%였다. 2) 엽령(葉令)에 따라 엽속(葉束) 및 엽장(葉長)의 변화(變化)는 크게 나타났다. 엽속(葉束)은 1년생(年生)의 경우 광도(光度)가 높을수록, 그리고 2년생(年生)은 상대광도(相對光度) 37% 구(區)에서 가장 많았다. 그리고 엽장(葉長)은 각(各) 처리간(處理間)에 큰 차(差)가 없었다. 이때 광도(光度)가 미치는 엽속(葉束) 및 엽령(葉令)에 대(對)한 기여율(寄與率)은 각각(各各) 39%, 27.8% 였고 엽장(葉長)은 2.5%였다. 3) 중량생장(重量生長)은 상대광도(相對光度) 100% 구(區)에서 가장 컸으나 점차 광도(光度)가 낮아짐에 따라 감소(減少)하는 경향(傾向)이었다. 광도(光度)가 미치는 기여율(寄與率)은 생중량(生重量) 및 건중량(乾重量)의 경우 38%와 7.6%였고, 엽건중량(葉乾重量)은 13.18%로 나타났다. 4) T/R 율(率)은 상대광도(相對光度)가 점차 낮아 질수록 증가(增加)하는 경향(傾向)이었다. 이때 광도(光度)가 T/R율(率)에 미치는 기여율(寄與率)은 7.0%였다. 5) 엽건중량(葉乾重量)과 타기관(他器官)의 생장량간(生長量間)에는 정(正)의 상관(相關)을 인정(認定)할 수 있었고 이들간에는 직선회귀(直線回歸) 관계(關係)에 있음도 알 수 있었다.