«= BULLETIN 1116, U. S. DEPARTMENT OF AGRICULTURE. 
him and with rice seed grown in the Southern States (Pl. I). How-_ | 
ever, at least three strains of this fungus were found, basing the 
difference on size of the sclerotia and the color of pigment produced — 
in certain types of media. 
One strain isolated from rice leaves was almost free from pigment — 
in culture; another strain from leaves produced a small quantity of 
pinkish eno on most media. One form from rice seed produced 
an abundance of pinkish pigment, while a second form seemed to 
be identical with one of the strains from leaves in that it produced 
a small quantity of pigment. On synthetic agar the mycelium of all 
forms developed for the most part beneath the surface of the medium, 
and the size and number of sclerotia produced correlated closely with 
the pigmentation on other media. The size of sclerotia was directly 
proportional to the quantity of pigmentation, and the number was 
inversely proportional. In addition to this sclerotial fungus, a 
number of fungi were found in the seed which were capable of causing 
staining and decay and a certain percentage of seedling injury. 
Among these were some of the common rice parasites, Piricularia and 
Helminthosporium. Other forms present were species of Epicoccum, 
Penicillium, Aspergillus, and Eusarium. Other genera occurred 
rarely and were not given much consideration. 
These fungi, no doubt, enter the kernels to a certain extent before 
they are mature. The spores probably lodge between the glumes 
at flowering time. Panicles of Honduras rice were collected about the 
time they were fully mature and were thoroughly dried at once. 
Seeds from these, 62 in number, were dehulled and treated for three 
minutes with 70 per cent alcohol. They were then immersed in 
mercuric-chlorid solution (1 to 1,000) for 10 minutes and placed in 
tubes of sterile agar and incubated at room temperature. Fungi 
were found to be present in 27 of these seeds. The percentage of 
infection was hardly as high as in seed collected from the same field 
after the rice had stood in the shock through a rainy season. 
The infection spreads, no doubt, if the rice remains shocked under 
warm, moist conditions. At the same time the infections already 
present have a tendency to spread through the kernels. Under 
such conditions sclerotia of the sclerotial type of organism are formed 
in the glumes and on the surface of the kernels. Such infected 
kernels ae are shriveled and very brittle. When conditions are 
very humid this fungus causes the kernels to become much enlarged 
and very irregular in shape, with sclerotia resembling those produced 
by ergot in grain. These distorted kernels are almost black in color 
(Pls. II and: IID), and the tissues are filled with a sclerotial develop- 
ment. Where the other fungi mentioned are present the kernels 
have the brown flecks, and the decayed tissue is a uniform brownish 

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