BROWN ROT OF SOLANACEAE. 



I8 3 



Result. Successful; the first signs appeared on the fifth day; weather exceedingly hot for last 4 days. The diseased 



stems of potato were swarming with short motile rods. Illustrated in Bull. 12, Division of Vegetable Phy- 

 siology and Pathology, 1896, pi. 1, fig. 1. 

 Tune S. Fifteen inoculations were made on pear tree (Japan), pepper, pepino, Solanum nigrum, Datura stramonium, 



tobacco, tomato, potato, using slant agar No. 1 of June 4, from culture used for inoculations of May 27. Each 



plant received many pricks. 

 Result. Succeeded on tomato, potato, Solanum nigrum, and Datura stramonium (fig. 88). The organisms in the diseased 



Daturas were short, motile bacteria. 

 June 15. Sixteen inoculations into Pelargonium zonale. Datura stramonium, Solatium carolinense, potato and tomato, 



were made with cultures derived from the same source as those used for the inoculations of June 8 and May 27. 

 Result. Failed, except on potato, the stem and tubers of which finally rotted. There was only a local multiplication 



of the bacteria in 2 green fruits of the tomato. 

 June 21. The plants used for these inoculations were 40 strong, growing tomato vines 10 inches high in 4-inch pots. 



Nos. 46 to 66 were pricked in middle of stem, and Nos. 67 to 85 in the tender tip of stem; many deep pricks 



were made in each case. The culture used was slant agar No. 3 of June iS, whose history is as follows: Made 



from a single colony on poured plate No. 3, June 14, from slant agar No. 1, June n, which was made directly 



from interior of stem of potato No. 13, inoculated May 27. 

 Result. Failed; at least there were no signs for 30 days. Possibly a wrong colony was used; at any rate the method 



was defective, as plate 



cultures should have 



been made direct from 



plant No. 13. 

 July 5. Egg-plants, cucumbers, 



tobacco, potato, Datura 



stramonium were used 



for these inoculations 



(30 in all). The leaves 



and stems were pricked. 



The culture used was 



slant agar No. 1, June 



18, from another colony 



on plate No. 3, June 14. 



The bacteria covered 



nearly the whole surface 



of the slant with a 



smooth, wet-shining, 



whitish, copious growth, 



crenate at margins, not 



sticky, possessing a 



moderately bad smell; 



the agar was not stained. 

 Result. Failed? No records 



found. Probably a 



wrong colony was used. 

 .4 ugust . Tomatoes in the field 



on James Island, South 



Carolina, were inocu- 

 lated direct from slime 



in stem of egg-plant 



from Charleston, S. C. 



Fifteen terminal, rather 



woody shoots of large 



plants were selected. 

 Result. Successful; all of the 



inoculated plants con- 

 tracted the disease, the Fig. 89.* 



wilt appearing slowly. 



None of the check-plants became infected. Rainy weather. 

 May 7, 1896. Tomato, Datura stramonium, and potato (2 watery shoots) were inoculated from tube No. 2, May 5, 



from interior of tomato stem from Lawrence, Massachusetts. The plants were healthy and 12 to 15 inches 



high, except the Datura, which was half as large and old. There were 7 inoculations. 

 Result. No record found. The inoculations probably failed. 

 June 1. Six plants, part tomato, part potato, were inoculated from peptonized beef-broth culture No. 3 May 29, 



made direct from the interior of stem of egg-plant from Charleston, South Carolina (1896). The inoculations 



were made into petioles, tender shoots, and leaflets. 

 Result. Very successful (Bull. 12, pi. 1, figs. 3, 4, 5). The organism in diseased tissues is a motile, short rod (see 



Centralblatt f. Bakt., 2 Abt., vn Bd., 1891, Tafel xi, figs. 41, 42). 

 June 75. Eight young plants (each bearing 6 leaves), part tomato, part potato, were inoculated in soft tissues in active 



growth by means of needle-pricks. The culture used was a peptonized beef-broth, tube No. 6, June 13, from 



No. 2, June 12 (broth-culture), from a colony on poured plate No. 6, June 4, from peptone water 1, May 29, 



which was a companion tube to No. 3, May 29, used on June 1. 



mm 



*Fig. 89. Cross-section of stem of Solanum nigrum, showing vessels occupied by Bacterium solanacearum. Plant 

 No. 34, 1896, inoculated from bouillon July n, in upper part. Collected July 24. Source of organism, South Carolina 

 egg-plant. All of the leaves were wilted when the stem was fixed in strong alcohol. Bacteria are confined to the heavily 

 shaded parts of the xylem, and inner phloem. Slide 119*. A few of the infected vessels are shown highly magnified 

 in fig. 90. 



