54 



PROTECTION OF PLAISTS, 1920-21 



GERMINATION OF TELIOSPORES OF PUCCINIA ANTIRRHINI 



By J. F. Hockey, B.S.A. 



At the twelfth Annual Meeting of this Society, Professor B. T. Dickson, 

 Macdonald College, presented a paper — "Some Plant Diseases in the Green- 

 house," — in which he made reference to a rust on snapdragons (Antirrhinum 

 Majus, L.) In that paper reference was made to the finding of both uredi- 

 niospores and teliospores, the latter being mush less plentiful. The uredinios- 

 pores, as stated, germinate readily in a few hours, but the writer has been unable 

 to find any record of the germination of teliospores in available literature. It is 

 the purpose of this paper to present the results of experiments, carried on under 

 Professor Dickson, on the germination of the teliospores of Puccinia Antirrhini. 



Source and Description of Material 



The material for these experiments was obtained from the College green- 

 houses on January 5th, 1921. A crop of snap-dragons had been growing in one 

 of the beds but, owing to a severe outbreak of rust, the entire crop was pulled up 

 and thrown on the compost heap. Specimens of badly diseased plants were 

 taken from this pile the following day, the plants having been severely frozen. 



The rust was determined as Puccinia Antirrhini, Diet, and Halw., accord- 

 ing to the description by Saccordo (7). The teliospores were found on the 

 branches and stems of the plant in elongate and round sori either mixed with 



Germinating teliospores of P. Antirrhini. Figs. 1 and 1, after 24 hours in hanging drop- 

 culture. Figs. 2 and 3, after 48 hours in culture, showing four-celled promycolia witli 

 sterigmata bearing sporidia on their tips. 



