14 
BULLETIN" 1015, U. S. DEPARTMENT OF AGRICULTURE. 
(1) Those of plants apparently infected, determined by visual inspec- 
tion only, and (2) those of plants actually infected, determined by 
cutting the stems and noting the appearance of the tissues. 
Table 6. — Comparative resistance to wilt of several varieties of tomatoes in 
Louisiana in 1920. 
Plants infected. 
Variety. 
Plants infected. 
Variety. 
J une 25, 
apparent 
infection. 
July 11, 
actual 
infection. 
June 25, 
apparent 
infection. 
July 11, 
actual 
infection. 
Per cent. 
6.6 
6.2 
6.3 
5.0 
15.0 
13.2 
1.2 
Per cent. 
55.7 
62.2 
69.3 
70.0 
75.4 
77.7 
77.9 
Earliana 
Per cent. 
47.6 
24.5 
58.4 
78.3 
60.1 
80.6 
Per cent. 
87.6 
Manyfold 
90.7 
92.7 
Stone 
96.1 
June Pink 
96.6 
Arlington 
Livingston's Globe 
97.2 
There is considerable difference between these varieties in per- 
centage of plants apparently infected, but not so much in percentage 
of plants actually infected. As apparent infection is somewhat 
closely related to degree of infection, the percentages recorded in the 
first figure column show the superior resistance of varieties developed 
for resistance to wilt. However, the resistance of Livingston's Globe 
was much higher in these tests than the writer has personally ob- 
served. In a test of 87 strains of the Globe variety at the Arlington 
Experimental Farm in 1920 the percentage of apparently infected 
plants was much higher than for the Marvel, Norton, Arlington, 
Columbia, or Louisiana Red. The Globe must therefore fluctuate 
considerably in its resistance to wilt. 
The report in Table 7 by Mr. L T . G. Swingle, of Columbus, Ohio, 
gives a fairly good comparison of the behavior of the Marvel variety 
in wilt-infested soil in a greenhouse as compared with commercial 
varieties. The Arlington, Columbia, and Norton varieties were used 
in this test, but only on a small scale, as they are rather large, heavy, 
and late for forcing. 
Table 7. — Comparisons of icilt-resistant and nonresistant varieties of tomatoes 
in a greenhouse at Columbus, Ohio, in 1919." 
Variety. 
Number 
ofplants. 
Average 
yield 
per 
plant. 
Average j yield 
returns ! ™" 
P er acre 
plant. acre * 
1,650 
Pounds. 
4.76 
3.23 
Tom. 
$1 02 22 
Nonresistant varieties, mostly Bonny Best 
5,160 
.70 15 
a Swingle.U. G. Successful greenhouse tomato crop. In Market Growers' Jour., v. 25, no. 11, p. 7. 1919. 
