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ANTHRACNOSE OF THE BEAN. 



(Glceosporimn lindemuthianum, Sacc. & Magnus.) 



For the past eight or ten years the gardeners of this city have lost most of their bean 

 crops from the attacks of a peculiar disease. The malady appears suddenly, frequent- 

 ly destroying the entire crop in one night. I have tried many ways of planting, dif- 

 ferent fertilizers, etc., but so far I have failed to discover a remedy. The only definite 

 information that I am able to give you in regard to the matter is that the disease is 

 always more abundant during warm, " muggy " weather.— (V. Anseman, New Orleans, 

 La.) 



Answer. The beans are affected with a parasitic fungus which grows 

 in the tissue of the pods, producing the large brown spots with which 

 you are familiar. The little pinkish, mealy tufts seen in the center of 

 the spots are the spores or reproductive bodies of the fungus. These 

 are easily blown about by the wind, and when they fall upon healthy 

 bean-pods they germinate, providing there is sufficient moisture present, 

 and ultimately produce similar discolorations to those referred to above. 



The disease is usually more abundant where the plants are too thick, 

 or where there is an excess of moisture in the soil. In some cases, 

 however, even the most vigorous plants are attacked by it, and on this 

 account it has come to be regarded by many gardeners as a most dan- 

 gerous foe. There is considerable doubt as to how the fungus lives 

 over winter, and it seems probable that this may be more easily deter- 

 mined from beans grown in the South, since the winter form will de- 

 velop earlier than with us. 



The probability is that the spores which you see on the spots, or other 

 spores of a similar nature, fall to the ground and retain their vitality 

 until spring, when they get upon the young beans. The pods are prob- 

 ably infected early, but the fungus needs moisture in order to develop, 

 and a long shower furnishes this. Hence, you find the pods spotted 

 immediately after. So far little is known concerning a remedy for this 

 disease. I would suggest, however, the following treatment in the hope 

 of discovering a remedy for the pest : 



1. Soon after the beans begin forming, spray the plants with a solu- 

 tion made by dissolving 1 ounce of hyposulphite of soda in 1 gallon 

 of water. Apply this mixture thoroughly to the young pods; it is per- 

 fectly harmless, and no injury to the plants or the person will result 

 from its use. Eepeat the operation when the pods are one-half or two 

 thirds grown, and again eight or ten days later. 



2. Apply as described above, but to different plants, a solution made 

 by dissolving one-fourth ounce of sulphide of potassium in 1 gallon 

 of water. The chemicals here mentioned are for sale by all druggists, 

 and they ought not to cost more than 10 cents per ounce. Besides this, 

 it will be well to carefully burn all the vines and diseased pods, and, if 

 possible, to select another site for your bean plot which will be as dry 

 and airy as possible. 



11244— No. 8 5 



