Abstract: During the period of 1957—1959, ergot strains Ce5, Ce5-29-1 and Ce5-35-3 of Claviceps microcephala (Wallr.) Tul. were cultivated on varieties of wheat, barley and rye. Strain Ce5 was shown to be very virulent to wheat, barley and rye, the severity of infection ranged from 56 to 96 per cent, rye being more susceptible than either barley or wheat. Among the varieties of rye, Shen-Nun-Polyploid was found to be the most susceptible (96% Spikes infected); Spring rye appeared to be less susceptible than winter rye, with 80—90% and 93—95% infected spikes respectively. The thousand-grain-weight of sclerotia produced by Ce5 varied with different hosts and decreased in the follwing order: rye, barley and wheat; they were 37—49g, 25—44 g and 21—34 g respectively. The alkaloid content of ergot produced by Ce5 varied within the range of 0.078—0.4%, ergot from Hull-less barley being the highest (0.4%) and the wheat variety Nan-Tai 2419 the lowerest (0.076%). The alkaloid content of ergot from ten varieties of rye varied within the range of 0.22—0.40% (1957—1959) and were close to that of the cultivated ergot from Hungary (0.297—0.483%). Of these rye varieties, Shen-Nun-Polyploid and Petcosk produced ergot which contained the highest amount of alkaloids (0.29%) while ergot from Voponoshk contained the lowest. Ergot from the barley variety "Blue Awn" contained 0.19% alkaloids while those produced by twelve varieties of wheat contained alkaloids not more than 0.25%. Under cultivation, virulence and alkaloid producing capability of Ce5-29-1 and Ce5-35-3 were comparable to that of their parental strain Ce5. Strain Ce5-29-1 appeared to be better than Ce5-35-3. A white variant Ce5-w was also cultivated and was found to be more virulent to four varieties of rye including Changpei. Considerable amount of alkaloid was also produced. Strains Sc2-4, Sc6-2 and Sc9-5 of Claviceps purpurea (Fr.) Tul. were cultivated on four varieties of rye; the percentage of infected spikes varied from 48 to 98 per cent and the alkaloid production was rather low (0—0.14%).