218 PHYTOPHTHORA PARASITICA. 



tendent of the Victoria Gardens, Bombay ; plants of lilac were kindly 

 supplied by the Superintendent, Kuiimuu Government Gardens. 



Young plants of Solanum tuberosum were inoculated with 

 zoospores. The plants showed signs of disease in twenty- four 

 hours. The leaves turned black and shrivelled up as if attacked by 

 Ph. infestans, and the plant wilted (Plate VIII A). No sporangia 

 were formed on the diseased parts but if they were transferred to 

 water sporangia were readily produced. When a very tender stem 

 was inoculated, from the diseased area a web of aerial sterile my- 

 celium was produced. The diseased area extended both ways. A 

 thick or an old stem took no inoculation, even when wounded. The 

 disease remained localised on inoculated mature leaves. Tubers 

 could be inoculated only through wounds. They produced a rich 

 aerial growth of mycelium but this was always sterile. 



Seedlings of Solanum ly coper sicum, about four to six inches high, 

 took the inoculation within two days (Plate VIII B). The photo 

 was taken three days after the plant was inoculated. The seedlings 

 soon wilted. No sporangia were produced on them but sec- 

 tions showed the presence of Phytophthora hyphse. When leaves of 

 older plants were inoculated they got blighted and blackened near 

 about the point of inoculation ; the diseased area was always localised, 

 even when growing points of big plants were inoculated. Fruits 

 could not be inoculated, even when wounded. 



The inoculation proved fatal to seedlings of Solanum Melongena, 

 only when they were about four inches high and bore two or three 

 small leaves. In this case also no sporangia were produced. The 

 effect of the inoculation in the case of big mature leaves was localised. 



Lilac plants did not take the inoculation vigorously. Inoculated 

 leaves turned black. Sporangia were produced only when the diseas- 

 ed leaves were placed in water. The leaf buds did not get attacked 

 when they were surrounded by a jacket of water containing motile 

 zoospores. This method was used with success by Klebahn 1 in 

 inoculating leaf buds of lilac with Ph. Syringce. 



1 Klebahn, H. loc. cit., p. 55. 



