THE CULTIVATION OF ERGOTS ON RYE

The cultivation of ergot on rye varieties with ergot isolates from different hosts was performed both in Peking and Harbin in 1957.In general,spring rye were more susceptible than winter rye.Varieties from Changpei and Chamoshih were the most susceptible ones among spring ryes and were heavily infected with isolates from Calamagrostis epigeios,Clinelymus dahuricus,Clinelymus sibidcus,Climelymus excelsus,rye and Agropyron spp.Ergot isolates from C.epigerios,were more virulent than those isolated from other hosts.Of the six isolates from C.epigeios tested,B₅ was the most virulent,causing 70% infection on different varieties of spring rye.B₁ was less virulent(causing more than 50% infection)while B₇ was least virulent(causing 5—10% infection). Injection of spore suspension into spikelets by means of hypodermic syringe resulted in higher percentage of infection than dipping method,while results with spraying method was rather poor.The percentage of infection increased with the increase of concentration of spore suspension,which was kept within the range of 600—9600 conidia per cubic millimeter. Ergot produced by strains of Claviceps microcephala on rye varieties were 34 times in weight as compared with those produced in nature on original host plants(C.epigeios).Strains B₁ and B₅ gave rise to ergots on different rye varieties containing 0.22—0.40% total alkaloids calculated as ergotoxine.The alkaloid content was much higher than that of the original rye ergots(0.06%)collected from different localities of North and Northeastern China.The figure also exceeds the required level for standard ergot(0.2% total alkaloid)as was listed in Chinese Pharmacopoeia,Strain B₅ had a higher capability for alkaloid production than B₁.Alkaloid contents of ergot also differed considerably with different rye varieties,and Chamoshih appeared to be the better variety than either Kongtzeling or Pinglu.