Effect of carbon, nitrogen and trace elements on growth and sporulation of the Termitomyces striatus (Beeli) Heim

摘要

Nutritional studies namely carbon, nitrogen and trace element requirements of Termitomyces striatus have been carried out. Amongst all the carbon compounds used, the most favourable in order of effectiveness are D (+) glucose, D (+) sucrose, maltose and D (+) raffinose. The fungus showed poor growth with lactose. Sodium nitrite served as the best inorganic nitrogen source for the growth of this fungus. Ammonium acetate, ammonium phosphate, ammonium oxalate, potassium nitrate and sodium nitrate supported fairly good growth of the fungus. Among different amino acids tested, maximum average mycelial dry weight was obtained with L-arginine followed by glycine and DL-tryptophan. The fungus showed poor growth with L--amino-n-butyric acid, L-cystine, L-cysteine HCl and DL-serine. The selected concentrations of trace elements also affected the mycelial growth of this fungus to a significant level. There is a gradual increase in growth (average mycelial dry weight) from control to optimum concentration of required trace elements beyond which it decreases. None of the trace elements required for growth are found to be completely fungistatic for the growth of this fungi. The fungus formed asexual conidia similar to that formed in the sporodochial stage in the termite garden of termites of the subfamily Macrotermitinae.