Abstract
The present paper deals with the results of studies on the nutritional behavior of the pathogenic fungus of the red wasting disease of Nori. The fungus was isolated from diseased fronds obtained from Matsushima bay.
1) The mycelial growth of the fungus was very poor on any of the CZAPECK's, HOPKINS's and RECHARD's media containing inorganic nitrogen source.
2) Amino acids were utilized well by this fungus as their nitrogen source. Of these amino acids, acidic amino acids were the most favoured. Inorganic nitrogen compounds were generally unsuitable as nitrogen source for mycelial growth.
3) For the carbon source, starch, sucrose and xylan were utilized fairly well by this fungus. Above all, starch gave the best growth of mycelium.
4) This fungus was auxoautotrophic to tested growth factors. For growth, this fungus does not appear to need a specific growth factor.
5) The range of the optimal concentration of NaCl for mycelial growth was narrow. Mycelial growth decreased significantly with the concentration of NaCl reaching above 2 percent.
6) From these experiments, it was concluded that the composition of the synthetic liquid medium suitable for the culture of Pythiu, n porphyrae is: glutamic acid, 2g; K2HPO4, 1g; KCl, 0.5g; MgSO4 7H2O, 0.5g; FeSO4 7H2O, 0.01g; soluble starch, 20g (or sucrose, 30g; xylan, 10g); dist. water, 1 liter; pH 7.0-8.0.
