Abstract:

 The present study deals with some factors influencing the mode of teliospore

germination of Yenia esculenta (P. henn.) Liou (Ustilago esculenta P. Henn.) which

is parasitic on water bamboo [Zizania caduciflora (Turcz.) Hand.-Mazz.]. The hyper-

trophied, immature smutted shoots of Z. caduciflora is used as a delicate vegetable in

China.

     Factors such as temperature, light, hydrogen-ion concentration, nutrient and oxy-

gen play an important role in spore germination.  Evidences have been obtained to

show that morphological changes of basidiosporophore  (conidio-promycelium)  have

been observed under some unfavorable conditions e. g., higher temperature, higher

hydrogen-ion concentration, poor nutrient, complete darkness, etc. The morphology of

the basidio-promycelium, however, remains unaffected.  On the basis of this unique

character, Liou (1949) proposed to erect a new genus (Yenia) for Ustilago esculenta

and a new family (Yeniaceae) for the order Ustilaginales. According to present study,

it seems to the writer that the validation of Yeniaceae is a reasonable and preferable

proposal and merits recognition.  The evolution and classification of the order are also

briefly discussed.