목련흰비단병균 Sclerotium rolfsii의 균사생장 및 균핵형성에 대한 thianine, biotin, nicotinic acid, Pyrido-xine, inositol과 DNA 및 RNA의 영향을 조사한 바 그 결과를 요약하면 다음과 같다. 1. 공시균은 thiamine 결핍균으로서 균사생장 최적 thiamine 농도는 20r/l이고 이농도를 초과하면 오히려 균사생장이 억제되어 150r/l에서는 무첨가구와 거이 비슷한 균사생장을 하였다. 2. 공시균의 생장에 있어서 thiamine의 첨가에 따른 질소원 이용도는 NH4NO3>(NH4)2SO4>asparagine>KNO3의 순위이며 질소원별 thiamine 최적요구량은 인 경우 12r/l, asparagine인 경우는 16r/l정도였다. 균핵형성량에 있어서는 KNO3>NH4NO3>asparagine>(NH4)2SO4의 순위로 질소원별 thiamine 최적량은 가 8r/l에서 균핵의 대부분이 형성되나 asparagine은 16r/l정도였다. 3. 배양액의 pH는 공시균이 생장을 개시하자마자 3.5정도로 급격히 떨어지나 그 이후로는 생장량이 증가함에 따라 완만하게 떨어졌다. 그러나 pH2.2 이하로는 내려가지 않았다. 4. Nicotinic acid는 공시균의 생장 및 균핵형성에 아무런 효과가 없었다. 그러나 thiamine 10r/l와의 공존하에서는 다소의 효과가 있는 것으로 nicotinic acid 7-10mg/l에서 가장 생장이 좋았고 그 이상에서는 생육이 억제되었다. 5. Pyridoxine, biotin 및 inositol은 배지의 질소원이 나 asparagine인 경우 모두 공시균의 균사생장 및 균핵형성에 아무런 효과가 없었다. 6. 공시균의 균사생 장에 대한 각종 vitamin의 상호효과는 thiamine, biotin, Pyridoxine, inositol의 4가지 combination에 의해서도 thiamine이 첨가되지 않으면 거이 효과가 나타나지 않았다. 그러나 thiamine+pyridoxine, thiamine + inositol, thiamine + biotin + pyrid oxine, thiamine + biotin + pyridoxine + inositol 구에 있어서는 thiamine단독첨가구와 동등 혹은 그 이상이지만 thiamine+biotin과 thianline+biftin+inositol구는 오히려 떨어졌다. 균핵형성에 있어서는 thiamine단독구에 비하여 각구 모두 약간씩 증가하였다. 7. 공시균의 균사생장에 대한 DNA와 RNA의 효과는 무첨가구에 비하여 다소 인정되는데 DNA보다는 RNA가 좀더 효과적이었다. RNA는 2-6mg/l에서 DNA는 6mg/l에서 가장 좋았다. 균핵형성에 있어서는 효과가 없 었다. 8. RNA의 농도가 증가함에 따라 또 thiamine의 농도가 증가함에 따라 균사생장량이 증가하는 것으로 thiamine의 존재하에 RNA의 효과가 뚜렷하게 나타났다. 그러나 균핵형성에는 효과가 없었다.

The study was performed to clear the effects of thiamine, biotin, nicotinic acid, pyridoxine, inositol, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) on the mycelial growth and the sclerotial production of Sclerotium rolfsii Sacc. isolated from Magnolia kobus. The results are abstracted as follows: 1. Tested fungus was thiamine- deficient and required thiamine 20r/l for maximum growth of mycelia. At higher concentrations than thiamine 20r/l, however, mycelial growth was decreased with increasing the concentrations and was inhibited little less than that of thiamine-free control at 150r/l. 2. The effecfivenesses of the nitrogen sources on the mycelial growth under the thiamine presence were recognized in order of NH4NO3>(NH4)2SO4 >asparagine> KNO3, and on the sclerotial production were KNO3>NH4NO3>asparagine>(NH4)2SO4. The optimum concentrations of thiamine were about 12r/1 in , about 16r/1 in asparagine on the growth of mycelia, and were about 8r/l in in asparagine on the production of sclerotia. 3. After the organism began to grow, the pH value of cultral filtrate was rapidly dropped down to about 3.5. Hereafter it was slowly fallen down as the growth amount was increased, but was not depreciated below pH 2.2. 4. Nicotinic acid was not effective individually on the mycelial growth and the sclerotial formation of tested fungus without thiamine, but slight effect of it was recognized with thiamine 10r/l, even though maximum growth was shown at 7-10mg/1. Beyond that concentration, however, mycelial growth was rather depressed. 5. When ammonium sulphate or asparagine as the nitrogen sources was used, pyridoxine, biotin and inositol had not any effectivenesses on the mycelial growth and the sclerotial production of examined fungus. 6. In the concentrations of thiamine, biotin, pyridoxine and inositol, as long as thiamine was not added in those, their correlating effects on the growth of the organism were not observed at all. Equivalent or more effects on the mycelial growth were recognized in combinations of thiamin + pyridoxine, thiamine + inositol, thiamine + biotin + pyridoxine, and thiamine + biotin + pyridoxine + inositol compared with thiamino alone, and in combinations of thiamine + biotin and thiamine + biotin + inositol, mycelial growth was inhibited rather than that of thiamine alone. Sclerotial production of those combinations was increased more than that of thiamine alone in dry weight. 7, The little effects of DNA and RNA on the mycelial growth of the organism were recognized compared with the control(DNA-and RNA-free), and RNA was more effective than DNA. Maximum growth of mycelia was observed at RNA 2-6mg/1 and DNA 6mg/l. No effectivenesses on the sclerotial production were recognized in the RNA and DNA. 8. Mycelial growth of the organism was increased with increasing the concentrations of the RNA and the thiamine, that is, the effectiveness of RNA was revealed apparently under presence of thiamine, but was not shown in the sclerotial formation.

• 金基淸