Effect of Ca2+, Mg2+, light, temperature and pH on athelial stage formation in Sclerotium rolfsii Sacc.

The role of the divalent cations, Ca2+ and Mg2+ as well as light, temperatu re and pH in the induction of sexual reproduction of Srlerotium rolfsiii in potato dextrose agar medium supplemented with Cyperus rotundus rhizome pow der was investigated. EDTA (ethylenediaminetetraacetic acid) at 15 mmol/l s uppressed hymenium induction without affecting growth or sclerotium formati on. This effect was reverted by the addition of divalent cations. Chlorprom azin, a calmodulin antagonist, and ruthenium red, an organelle Ca2+ channel blocker, did not have any effect on the induction process. continuous whit e light inhibited the sexual stage formation while blue, green and red ligh t did not, Maximum percent area covered in the Petri dish by basidial stage was produced under complete darkness at a range of pH 4-8.