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BACTERIA IN RELATION TO PLANT DISEASES. 



September 28, 1903. Looked at the sweet corn on Arlington Farm. There are large patches in 

 the middle of the field where the seed did not come up at all (stiff soil) . There is not a good stand 

 anywhere except the first two rows on the south side. Some of the plants look as though they were 

 going to be diseased. 



Cut out 6 typical cases from the Crosby's Early plot and 2 cases from the Cosmopolitan. There 

 is unquestionably much more disease, but the plants will be allowed to remain a little longer, so that 

 the signs may become more evident. 



TABLE 10. Varieties Planted and Behavior on the Other Farm. 



*3p per cent, if the missing plants are included as diseased. 



fOne only of the six strains of this variety, and the one showing least disease in July. The others 

 were not examined in August. 



October ip, 1903. Tenny and Rorer cut out and examined every plant in the 14 rows of Old 

 Colony sweet corn planted on July 29 at the Arlington Farm. The corn at the lower (west) end and 

 in the first two rows (south side next the fence row) was about 3 or 4 feet high and well tasseled out 

 and looked fairly well. In the upper (east) and central part of the plot, however, the corn had made 

 a very poor growth, many of the plants being only about a foot high and less than half an inch in 

 diameter (due to poor soil). The examination resulted as follows: 



OLD COLONY. 



Stalks found to be healthy, 6,235; stalks found to be diseased, 65. 

 Total, 6,300; diseased, i per cent. 



Many of the diseased stalks showed only two or three yellow bundles, while only a few were very 

 badly diseased. Some of the most badly affected were put into alcohol. 



October 2 4 and 27, 1903.- The other varieties of corn were cut and examined by the writer, assisted 

 by Messrs. Tenny, Rorer, and Deane B. Swingle, with the following results: 



COSMOPOLITAN. 



Stalks found to be healthy, 1,905; stalks found to be diseased, 366. 

 Total, 2,271; diseased, 16 per cent. 



It appeared on the start that there were many more cases in the lower moister land, where the 

 corn had made the best growth, than on the side hill or the level land on the top. When classified in 

 this way the result shown in table 1 1 was obtained : 



TABLE 1 1 . Effect of Slow Growth on General Infection. 



Owing to the labor involved and the bad weather the entire plot was not counted, but only aver- 

 age portions of it. The same method was followed with the remaining varieties ; the only variety 

 counted in full being Old Colony. 



COUNTRY GENTLEMAN. 



Healthy stalks, 881; diseased stalks, 32. 

 Total, 913; diseased, 3.5 per cent. 



