September, 1955 
cation of the formula used in determina- 
tion of rot severity indexes in the labora- 
tory tests. Complete decomposition of the 
corms was considered the most severe re- 
sult of the disease and was assigned a value 
ForsBerG: Fusarium Diseaszt of GLADIOLUS 
495 
of 3. Brown rot and vascular symptoms 
were considered equal in severity and were 
assigned a value of 2. Thin basal dry rot 
was considered less severe and was given 
a value of 1. Absence of symptoms rated 
Table 23.—Severity indexes (obtained by use of formula on page 496) for the disease pro- 
duced by 20 isolates of Fusarium on four gladiolus varieties in greenhouse tests, 1952.* 
| IEUES seat SS eee eer 
REC KHING Re ele ete Sevens 
‘Cina ING eee 
VARIETY 
0) AVERAGE 
4 DISEASE 
aes Moearet Picardy Variation INDEX 
56.1 0.0 92.6 63.3 53.0 
20.0 6.7 TET 3343 BAD 
100.0 90.0 94.4 80.0 91.1 
80.3 36.7 86.7 80.0 70.9 
40.0 1133.3) 30.0 46.7 3) 5) 
SGnS 0.0 80.0 30.0 85) 
100.0 80.0 95.2 76.7 88.0 
80.0 0.0 50.0 63.3 48.3 
96.7 50.0 80.0 20.0 61.7 
66.7 6.7 0.0 26.7 25.0 
533 6.7 16.7 0.0 19.2 
100.0 96.7 100.0 50.0 86.7 
20.0 0.0 26.7 0.0 ela? 
100.0 60.0 36.7 20.0 54.2 
20.0 20.0 56.7 10.0 26.7 
S355 66.7 63.0 70.0 58.2 
100.0 96.7 100.0 70.0 91.7 
80.0 66.7 Bio), 7 0.0 50.8 
46.7 13.3 86.7 283 42.5 
26.7 0.0 86.7 43.3 39.2 
DB! 0.0 40.0 10.0 18.3 
20.0 0.0 46.7 138) 20.0 
6.7 0.0 10.0 6.7 5.8 
*Symptoms in all varieties except Margaret Fulton were due in part to organisms other than the isolates used for 
inoculation, as explained in the text. 
Table 24.—Severity indexes (obtained by use of formula on page 496) for the disease pro- 
duced by 13 isolates of Fusarium on four gladiolus varieties in greenhouse tests, 1953. 
VARIETY 
AVERAGE 
a DISEASE 
phe Dr. F. E. Margaret eee Elizabeth cress 
| Bennett Fulton tos the Queen 
AUD i oo 2 re 100.0 91.7 60.0 66.7 79.6 
LBs be ee 1p) 6e7, 76.7 DIS) 28 44.7 
SET saad te re 3313 0.0 0.0 6.7 10.0 
SS mapa Mo Lk Sila il 66.7 133 | 33 53.6 
SSIS) Send ono Sid ee ees 47.6 6.7 20.0 | 5325 31.9 
OMe Ss Se ts. Sars 28.6 il il 0.0 0.0 9.9 
SUID aes, acces oD 28.6 18.5 0.0 0.0 RS 
GDA) ee Se 62.5 29.6 50.0 | 30.0 43.0 
SOHAL a 0.0 0.0 0.0 | 0.0 0.0 
SUPED2 Baa a ee ea 13 | 10.0 41.7 | 0.0 16.2 
SNES), 5a .gccl ara 66.7 | SOe7 20.0 26.7 SEAS 
S1Q)a28S) ot iO eas ae a a 1N(65.5.7/ | 63.3 30.0 0.0 PLU RS) 
Sg ke pens Oe ene BOO lis £222 40.1 66.7 44.7 
(Chietel ale (oye) (ee ae 0.0 0.0 0.0 0.0 0.0 
KheclaING Aes da tees elem ens D5) 0.0 0.0 | 0.0 Sil 
(Cie Ns ee ee | 0.0 0.0 10.0 | 0.0 D5 
