
534 Ruporr or tae HorvTIcuULTURIST OF THE = 
: ° y yee bys ‘ ist a ay 
pits with red borders. At first these are usually circular, but 
afterwards may become more irregular in outline, sometimes by —_— 
coalescence forming very large patches. Along the edges of the 
pods it is seen in narrow strips of dark color. The pits above  __ 
mentioned are commonly bordered by a narrow reddish discolora- —— 
tion between) the diseased portion and the healthy zreen tissue | 
of the pod. | ri 
APrEAKANCE OF SPORE MASSES.— Soon after the termite of a i 
spot, there appears in the central portion of the diseased area Aa 
pinkish white dots about the size of pin points. These dots are 
caused by exudations from the tissues which the fungus has e 
filled with its black threads, and they consist of spore masses; that it 
is to say, the spores which the fungus has produced to spread the — 
disease are here pushed forth in masses. These are also well Bs, 
illustrated in Fig. 2. The spores are held together in masses 
this way by some substance which readily dissolves in rain or : 
dew, after which they may be scattered to other plants by winds, _ 
insects or passing animals. This provision of the fungus for 
spreading its germs to other plants seems to afford a reasonable — oi 
explanation for the opinions held by many farmers, that the % 
disease does most damage in damp locations, and that cultivation ; 
when the plants are wet with rain or dew is apt to spread the ; 
disease more rapidly. The spores are produced by the anthrae- 
nose on whatever part of the plant it may happen to be living, but — 
probably are formed in greatest abundance on the succulent tis- ae 
sues of the pod. an Ae 
In the anthracnose the bean plant has a powerful and persist- % 
ent foe. If present in the seed it attacks the young plant from ie ‘i 
the moment it starts to germinate and keeps up the warfare until 
it has succeeded in establishing itself in the newly formed seed 
ready for another season’s campaign. By injuring the foliage it .~ 
weakens the plant so that it lessens the yield im this way, and also 
by its attacks on the pod prevents them from filling perfectly, ifat 
all. On the seed it causes specks, pits, wrinkles or blisters, and all | 
degrees of discoloration. Sometimes the discoloration is so faint 
as to be scarcely noticeable. As demonstrated by Dr. Halsted, _ 4 
and abundantly confirmed at this Station, these infected beans 
carry the disease from one season to another. CO 






