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A PARASITIC BOTRYTIS ON PEPPER AND LETTUCE. 53 
method, then, is efficient in the production of rapid infec- 
tion, while the sclerotia serve to tide the fungus over adverse 
conditions. 
Young lettuce seedlings, planted in flats, were on several 
occasions destroyed by Botrytis. Here the symptoms were 
practically the same as in the “drop,” except that the stems 
were encircled near the ground by the mycelium and cut off, 
producing a typical “damping-off.” Conidia and a few 
sclerotia were developed from the mycelium, which lives 
saprophytically on the dead tissues of the fallen seedlings. 
In the same manner, tomato seedlings in a number of flats 
were destroyed by the fungus, causing the characteristic 
“damping-off.” 
In November the poinsettias (Euphorbia pulcherrima) 
were infected by a Botrytis. In general, the symptoms of 
the disease were similar to those described by Spaulding (52), 
the flowers, green leaves, and in some cases even the colored 
leaves of the involucre being attacked. The fungus seemed to 
flourish on the stigmas, the spores, after germination, ap- 
parently living for some time saprophytically on the stigmatic 
exudation before becoming parasitic. The mycelium soon 
permeated the flower clusters, which fall off after a short time. 
In falling, the flowers strike the leaves and in some cases 
adhere to them, bringing about conditions favorable for new 
infections. On the leaves the disease first appears as light 
brownish spots. The fungus seems to attack the leaves in 
such a manner that the latex of the plant is excreted through 
the diseased spots and hardens on exposure to the air. Here 
again the mycelium first lives as a saprophyte and later be- 
comes parasitic. The excretion of latex is the most char- 
acteristic symptom of the disease, as it is found on all 
plants attacked. 
Another peculiar characteristic of the disease is that the 
infected areas are localized, considerable portions of the leaf 
remaining free from the parasite. Finally the petiole be- 
comes weakened and the leaf drops off. In this way the whole 
stem is defoliated, leaving only the red-colored leaves at the 
