60 CROWN-GALL OF PLANTS. 



alfalfa gall organism isolated from galls on alfalfa, produced in the 

 greenhouse by inoculation. 



Result. — June 25, 1910: No galls on either set. The trees were also 

 examined before June, but no record was made of the date. 



ALFALFA ON SUGAR BEET. 



Inoculations of June 14, 1909 (Brown). 



The same set of cultures used for inoculating alfalfa this date were 

 used to inoculate 3 sugar beets in the open bed. The part of the 

 root just below the surface of the soil was inoculated, using pure agar 

 streak cultures 4 days old. 



Result. — August 20, 1909: Two of the beets had large galls; diame- 

 ter nearly 2 inches. One of the beets could not be found. 



Inoculations op July 16, 1909 (Brown). 



Five young sugar beets in pots were inoculated at the crown with 

 agar cultures 4 days old. 



Result. — August 20, 1909: Galls had formed on 4 of the sugar 

 beets. They were small, however, because the plants had become 

 pot-bound and had grown very little. 



On August 23 a photograph was made (PI. VII, fig. 3). On the 

 lower roots of this plant were also some small nematode galls. 



PEACH ON DAISY. 



Inoculations op December 2, 1907 (Brown). 



Ten daisy plants were inoculated in the stem b}^ needle pricks from 

 agar colonies obtained by the poured-plate method from a peach gall 

 November 26, 1907. The plants were in pots in the greenhouse and 

 were in a good growing condition. They were inoculated near the tip. 



The variety of daisy used was Queen Alexandra, 4 plants being new 

 ones from a firm in Philadelphia, where the gall disease of daisy was 

 unknown. 



Result. — January 9, 1908: Each of the 10 inoculations gaA'e tumors; 

 4 check plants remained free from infection, as did also the uninoc- 

 ulated parts of the infected plants. 



Inoculations of December 4, 1907 (Smith). 



Thirty-six plants of the white Paris daisy were inoculated with 

 bacteria plated November 23 from the interior of a peach gall received 

 from a nursery in Maryland. All the inoculations were made by 

 needle punctures, making 5 or 6 pricks. The plants were 12 to 14 

 inches high and growing rapidly, so there was an abundance of soft 



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