Preliminary tests with new compounds against larvae of the tobacco and tomato hornworms

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Title:
Preliminary tests with new compounds against larvae of the tobacco and tomato hornworms
Physical Description:
17 p. : ; 27 cm.
Language:
English
Creator:
Stahl, C. F
United States -- Bureau of Entomology and Plant Quarantine
Publisher:
U.S. Dept. of Agriculture, Agricultural Research Administration, Bureau of Entomology and Plant Quarantine
Place of Publication:
Washington, D.C.
Publication Date:

Subjects

Subjects / Keywords:
Tobacco hornworm -- Larvae -- Control   ( lcsh )
Tomato hornworm -- Larvae -- Control   ( lcsh )
Genre:
federal government publication   ( marcgt )
non-fiction   ( marcgt )

Notes

Statement of Responsibility:
by C.F. Stahl ... et al..
General Note:
Caption title.
General Note:
"E-639."
General Note:
"March 1945."

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 030287134
oclc - 779542322
System ID:
AA00025096:00001

Full Text
LIBI-ARY
STATE PLANT BOARD
March 19I.5 E-639

United States Department of Agriculture
Agricultural Researoh Administration
Bureau of Entomology and Plant Quarantine

PRELIMINARY TESTS WITH NEW COMPOUNDS AGAINST LARVAE O' TEE
TOBACCO AND TOMATO HORNWQRMS

By C. F. Stahl, W. A. Shands, F. S. Chamberlin, and
L. B. Scott, Division of Truck Crop and Garden Insect
Investigations

Summary

Laboratory tests of nearly 300 materials, mostly synthetic organic
compounds, against larvae of the tobacco hornworm (Protoparce sexta
(Johan)) and the tomato hornworm (P. quinquemaculata (Hawi.)) haveeen
conducted at Oxford, N. C., Quincy, Fla., and Clarksville, Tenn. Lead
arsenate, cryolite, and paris green were included for comparison. The
highest mortalities were obtained with the various arsenicals and
cryolite. Of the other materials tested, the 20 that appeared to be the
most toxic are listed in alphabetical order as follows:

2-Acetamnidofluorene 4,6-Dinitro-o-cresyl acetate
p-Aminoazobenzene 1, 4-Diphenylsemicarbazide
p-Aminoazobenzene hydrochloride 2-Fluorylamine
Antimony trisulfide N-Nitrosodiphenylamine
Copper cyanamide Phenothiazine
Cuprous cyanide Phthalonitrile
DDT Xanthydrol
Diazoamlnobenzene Xenylamine
p,p'-Difluorobiphenyl Zinc cyanamide
4,6-Dinitro-o-cresol Zinc mercury thiocyanate

Of these materials, 4, 6-dinitro-o-cresol, 4,6,dinitro-o-oresyl
acetate, xanthydrol, and xenylamine caused injury to the plants under
the conditions of the laboratory tests.

Some of the more promising materials were tested against the tomato
hornworm, which appeared to be easier to kill than the tobacco hornworm.



Introduction

Exploratory tests on the toxicity of new compounds, particularly
organic compounds, were made on the tobacco hornworm (Protoparce sexta
(Johan.)) and the tomato hornworm (P. quinquemaculata (Haw.)) at three
laboratories of the Bureau, and the results are given by the laboratory
leaders in the following sections of this circular. The tests at Oxford,
N. C., are presented by C. F. Stahl and W. A. Shands; those at Quincy,
Fla., by F. S. Chamberlin; and those at Clarksville, Tenn., by L. B.
Scott.

APR 2 19g45





2 -


Some of these tests were not sufficiently replicated to warrant
definite conclusions regarding the possible value of the materials.

TESTS AT 0XFCRD, N. C., 1936-4.3 3

Since the Oxford, N. C., laboratory was established in 1935,
'-. -ts of new compounds have been conducted there almost continuously
for the purpose of determining their toxicity to the hornworms in-
festing tobacco. The majority of the new materials considered were
organic compounds obtained from the Division of Insecticide Investi-
,tions. Many had previously been found by other investigators to be
toxic to certain insects other than hornworms. Most of them were first
tried against hornworms in unreplicated tests, or screening tests,
designed to select for more thorough study those that were toxic to Scme
extent to these insects. Very few, however, appeared to warrant further
Investigation. The technique was varied slightly as the studies pro-
gressed. The work was carried on under the direction of W. A. Shands
during the period 1936-39 and was continued by C. F. Stahl through 1943.

The tobacco hornworm is the most prevalent and injurious species
in the flue-cured tobacco area. It was used exclusively in the screen-
ing tests, but the tomato hornworm was included in most of the others.
Both species are available in satisfactory numbers, but since their
periods of development do not coincide, it was seldom possible to have
an adequate supply of larvae of both species on hand at the same time.

Some materials were applied as dusts, others as sprays. The dust-
ing was accomplished by means of a precision dusting apparatus, which
was developed at Oxford 2? The dusts were allowed to settle on small
tobacco plants set in 10-inch flowerpots or on fresh tobacco suckers
placed in small bottles of water. After the.dusting the plants were
infested with 10 third-instar hornworms. In most cases the sprays
were applied to circular disks of tobacco leaves by means of a paint-
gun sprayer until the deposit reached the drip stage. After the plants
had dried, 5 second instars were placed on each leaf disk. The plants
were kept in cages, either outside or in the insectary, and the disks
were kept in Petri dishes. The mortality was recorded at the end of 4
days. Prior to 1939 the larvae were reared in Petri dishes, but after
that they were reared on growing tobacco plants in the insectary. The
settling time for the dusts in the dusting chamber ranged from 1 to 2
minutes. There were deviations from the above procedure, however, as
will be indicated.

I/ J. P. Vinzant conducted the tests with third instars in 1936 and all
the laboratory tests in 1937; T. F. Henderson conducted the laboratory
tests in 1938-40; and C. Levin assisted with these tests during 1941-43.

2/ Vinzant, J. P. An apparatus for dusting individual plants. U. S.
Bur. Ent. and Plant Quar. ET-105, 1 p., illus. 1937. [Processed.







Among the first test was a series conducted fcr th1 -,_rpose -'
comparing the toxicitles of certaiv- homologs of paris gr1 to third _
instars when dusted. on potted plants. Lime was used as "ne diluent.
The results are presented. in table 1.

Table l.-Toxicity of certain homologs of paris green when appli6`
&usts to third-instar tobacco hornworms on potted plants. Oxford,
N. C., 1936

............. .....D dilution : Larvae : .........Fee....
Materials :with lLm : used. Mortality: Feeding
wit lieusd


Cottonseed-oil green


Soybean-oil green




Copper stearoarsenite


Paris green


Number
20
180!
100
6o


None
1:2
1:6
1:10

None
1:2
1:6
1:10

1:P
1:6

1 2
1.5
1:6
1:10


10
1801
100
60

300o
6o

6o
120 /
i00
60


Percent
100
97
78
62


100
94
75
53

71
90

100
92
100
92


Slight
do
do
Moderate


Very slight
Slight
do
Moderate

S1I cht
do

Very ) 11 -.1
do
do
do


1/ Replicated tests, 60 larvae in


..Rch r ,- l 'at .


During the 1936, 1937, and 1938 seas.- 150 cr,.7Anic compounds w? r*
tested as sprays. The results of tests *.ritth irjt'rlal1 that gave at least
20 percent mortality are listed, in table 2 in the orde ... the toxicity
demonstrated.







Table 2.--Toxicity of sprays containing organic compounds to second-
uinstar tobacco hornworms on leaf disks. Oxford, N. C., 1936-38. Tests
not replicated
Dilution : :


Materials


: by weight
: with water


Larvae
used


Number


Mortality: Feeding


Percent


Lewd arsenate
Paris green and lime (1:6)
4,6-Dinitro-o-cresol /

p, p -Difluorobiphenyl
p-Iodosonitrobenzene
2-Thiocoumarin

2-Fluorylamine

2-Acetanidofluorene
Zinc mercury thiocyanate

Xenylamine
3-Chlorodibenzofuran
N-Nitrosodiphenylamine

Xanthydrol
p-Iodonitrobenzene
p-Iodoxynitrobenzene
Copper isoamylxanthate and
diisoamyl xanthogen (equi-
molecular mixture)
Bis(o- aminophenyl) disulfide
Zinc cyanamide
p-Nitrophenyliodochloride
4,6-Dinitro-o-cresyl acetate
beta-Aminoanthraquinone
Phenyl disulfide
2,6-Dibromo-4-nitrophenol _
2,6,7-Trinitrofluorenone
Copper cyanamide

9,9-Di chlorofluorene
beta-Iodonaphthalene
2-(2-Hydroxy-6-keto-4, 4-
dimethyl-delta' -cyclohexenyl-
methyl)-5,5-dimethyl-l, 3-
cyclohexanedione
2,4-Dinitrophenol i/
3-Nitrodibenzofuran
9-Fluorenone
9-Chlorofluorene


1:400
1:200
1:200
1:400
1:400
1:400
1:200
1:400
1:200
1:400
1:200
1:200
1:400
1:400
1:400
1:200
1:400
1:400
1:400
1:400


1:200
1:400
1:200
1:200
1:200
1:200
1:400
1:200
1:200
1:200
1:400
1:200
1:400



1:200
1:200
1:400
1:200
1:200
1:400


96
100
100
100
100
100
100
86
84
100
100
100
96
96
94
92
90
90
86
86


69
82
82
80
80
80
72
72
72
60
32
68
64



64
60
58
56
56
52


Very slight
do
None
do
do
Slight
Very slight
do
do
do
do
4.0
do
do
do
Slight
do
Very slight
Slight
do


do
Very slight
Slight
do
Very slight
Slight
do
Very slight
Slight
Moderate
do
Slight
Very slight



Normal
Moderate
Very slight
Normal
Moderate
do








Table 2--(Continued)


Dilution :
Materials : by weight : Larvae: Mortality: Feeding
: with water : used :
Number Percent


Sodium sulfoleate
p-Bromobiphenyl
9-Acetylcarbazole
2,3-Diaminophenazine
p -Phenylene-bis (amnonium-
2-benzothiazolyl) sulfide
4. 6-Dinitro-o-oresol methyl,
ether
5, 7,8-Tetrahydro-l-
naphthylthiourea
Copper butylxanthate and
dibutylxanthogen
1-Phenylbenzoxazole
1 -Benzothiazolyl-p-
nitrobenzyl sulfid-e
p-Aminoacetanll ide
9-Fluorenol
1 -Benzothiazolyl-p-
bromobenzyl sulfide


1:200
1:400
1:400
1:200

1:200

1:400

1:200

1:200
1:400

1:201
1:400
1:200

1:200


Norma.
Slight
d.o
d.o

Moderate

Slight

Normal

do
Slight

Moderate
do
Normal

Normal


/ Caused severe burning of the


foliage.





- 6 -.


The following materials were comparatively nontoxic at the dilutions
tested, and. in most c&ses permitted moderate to normal feeding:

Diluted. 1:400


T> -Acetotoluide
:11 F TInophenol
'I-inophenylmethyl sulfide
bi. hranilic acid
..thraquinone
29 2' -Azobis(thioani sole)
'*.p4 -Azobis(o-anisidlne)
Benzanilidje
Benzid.ine
I DB .zothiazolyl-cyclohexylamnonium sulfide
S-Benzoyl-l-mercaptobenzothiazole
N- (1l-Benzoxazolyl) cyclohexylamine
Benzyl disulfide
2-Bromo-5-phenyl-l,3-cyclohexanedione
Carbazole
beta-Chloroanthraquinone
2-Chlorofluorene
2-Chloro-2-nitro-diphenylamine
N-Cyclohexylacetamide

N-Cyclohexylbenzamide
Dibenzothiophene
4,41 -Dibromobiphenyl
4-(2,5-Dichlorophenylazo)-o-cresol


4, 4 -Di iocLdob iphenyl
2,2 -Dinitrobiphenyl
2-Fluorenol
p -Hydroxyb iphenyl
o-Iodoaniline
p-Iodobiphenyl
Methy-o-nitrophenyl sulfide
p-(2-Naphthylazo)-
dimethylaniline
p-Nitrobenzyl mercaptan
p-Nitrobiphenyl
4-(p-Nitrophenylazo)-
resorcinol
Phenacetin
Phenothiazine-S-oxide
4-Phenylazo-m-cresol
4-Phenylazo-o-cresol
4-Phenylazore sorc inol
1- (p-Toluenemthylmercapto) -
benzothiazole
Tri-(thiovanillin benzoate)
Xanthone


Diluted 1:200


2-Acetoxyfluorenone
Allantoin
2-Amino-9 -fluorenol
2-Aminofluorenone
p -Aminophenylanmonium-l -
benzothiazolyl sulfide
Anthracene
Anthrone
Barium sulfoleate
9-Benzalfluorene
1-Benzothiazolhydroxymethyl
sulfide
alpha-Benzoyl-beta-
(m-nitrophenyl)ethylene oxide
alpha-Benzoyl-beta-phenylethylene
oxide
Bis(l-benzothiazolyl) disulfide
9,9 -Bis (l-hydroxy-2-naphthyl) -
fluorene anhydride
2-Bromo-5,5-dimethyl-l, 3-
cyclohexanedione


Calcium sulfoleate
alpha-(p-Chlorobenzoyl)-beta-
(m-nitrophenyl)ethylene oxide
alpha-(p-Chlorobenzoyl) -beta-
phenylethylene oxide
p-Chlorobiphenyl
Chrysene
Chrysylamine
Copper ethylxanthate and
diethylxanthogen
Copper methylxarithate and
dlimethylxanthogen
Copper propylxanthate and
dipropylxanthogen
Coumarin
1,2,3, 4-Dibenzophenazine
9,10-Dibromoanthracene
2,7-Dibromo-9-benzalfluorene
2,7f-Dibromofluorene
2,7-Dibromo-9-(o-ohlorobenzal) -
fluorene





-7


Diluted 1:200 (continued)


2,7 -Dlibromo-9-furalfluorene
9, 9-Di (p-hydroxyphenyl) fluorene
5,5-Dimethyl-l, 3-cyolohexanedlone
1, 2-Dinitrobezene
Diphenylamine, sulfur, and
oleio acid
2, 3-Diphenylquinoxaline
2-Fluorene acetate
9-Fluorenol acetate
9-Fluorenone oxime
9-Fluorenone oxime acetate
9-Fluorenone oxime benzoyl eater
9-Fluorenone phenylhydrazone
9-Furalfluorene
9-Furylfluorene
2,2' -Hydrazobis (thioani sole)
Isonlitrosoaoetanilide
10-Nitroanthroane
m-Nitrobenzaldehyd.e
Nitroohrysene
6-Nitro-2, 3-diphenylquinoxaline
2-Nitrofluorene
2-Nitrofluorenene
1-Nitronaphthalene
1-Nitro-2-naphthol
p-Nitrophenol
alpha- (m-Nitrophenyl) -beta-
(p-toluyl) ethylene oxide
2-(p-Nitrophenyl)-3-
phenylquinoxaline
Phenyl-beta-naphthylamlne
alpha-Phenyl-beta- (p-toluyl) -
ethylene oxide
2-Phenyl-l- (o-toluino) -alpha-
naphthimldiazole
5-Phenyl-l, 3-oyolohexaned.ione
alpha-l, 2,3, 4-Tetrahydro-2, 3-
diphenylqulnoxaline
2, 4, 6-Triiodophenol
2,4,6-Trinitrotoluene
Zino sulfoleate





-8-


Some of the compounds, particularly those that had shown considerable
toxicity in the spray tests, were tested, as dusts daring 1937 and 1938.
Only a few of the materials were tested at one time. In a few oases the
tests were repeated. The results of these tests are presented in table 3.

Table 3.-Mortality of tobacco hownworms on tobacco foliage dusted with
materials diluted with clay or kaolin; dust allowed to settle l1 minutes.
Oxford, N. C., 1937-38.....
Material : Dilution Larvae : Average : Feedin
: by weight used : mortality:
Number Percent

Third instars on potted plants, dosage 125 mg.


Paris green(diluted with lime)
Xanthydrol I/
4,6-Dinitro-o- cresyl acetate /
Xenylamine 2,3/
Cryolite (synthetic)
3-Chlorodibenzofuran 2/
p-lodosonitrobenzene


1:6
1:1
1:1
1:1
1:1
1:1
1:1


200
6o
60
60
100
60
120


Very slight


Slight
Moderate
do
Normal


Third instars on potted plants, dosage 150 mg. 4/


Zinc cyanamide

Copper cyanamide


1:1
1:2
1:1
1:2


6o
50
60
100


Slight
do
Moderate
do


Third instars on potted plants, dosage 250 mg.


Xenylamine ?/
Xanthydrol I/


1:2
1:1


50
100


Moderate
Slight


Third instars on tobacco suckers, dosage 125 to 150 mag.


Cryolite (77.8% Na AIF )
Zinc mercury thiocanaxe
2-Aceteamidofluorene
2-Fluorylamine
N-Nitrosodiphenylamlne
Copper cyanamide
Zinc cyanamide
2-Thiocoumanxin
Copper isoamylxanthate and
dii soamylxanthogen 2/
Copper ethylxanthate and
dietbylxanthogen


None
1:1
1:1
1:1
1:1
1:1
1:1
1:1

1:1


60
60
60
60
180
60
60
120

60


100
98
83
82
64
58
57
48

28


None
Very slight
Slight
Very slight
Normal
do
Normal
do

do


1:2 60


7 Co




-9-


Table 3--(Continuedl)


Material


SDilution
" by weight


Larvae : Average : Feeding
used. mortality :


Number Percent
Second instars on leaf disks, dosage 125 mig.


Copper propylxanthate and.
dipropylxanthogen
Copper ethylxanthate and
dietbylxanthogen
Copper isoamylxanthate and.
diisoamylxanthogen &
Copper methylxanthate and.
dlmethylxanthogen
Copper butylxanthate and.
dibutylxanthogen


1:2

1:2

1:2

1:2

1:2


Second instars on potted plants, dosage 125 mg.


Copper isoamyixanthate and
diisoamylxanthogen /

2-Thiocoumarin


1:1
1:2
1:2


60
100
100


do
do
do


Second instars on potted plants, dosage 150 mng.


Zinc mercury thiocyanate
2-Acetamidofluorene

2-Fluorylamine

2-Thiocoumarin

2,6, 7-Trinitrofluorenone


1:1
1:1
1:2
1:1
1:2
1:1
1:2
1:1
1:2


110
120
50
60
100
60
50
120
50


Slight
do
do
Very slight
Slight
Normal
d.o
d.o
do


Caused severe burning.
Diluted with clay and redwood flour.
Caused some burning.
Allowed to settle 2 minutes instead of 11 minutes.
Equimolecular mixture.


:by weiaht




- 10-


During 1937 and 1938 several of the materials that showed, promise
when sprayed, on leaf disks were sprayed on potted tobacco plants or
fresh tobacco suckers. The applications were made with a DeVilbiss
sprayer. The spray was directed on the plants for 25 to 40 seconds and
then 10 seoond- or third-instar hornworms were placed. on each plant.
The results are shown in table 4.

Table 4.--Mortality of tobacco hornworms placed on foliage sprayed with
various orgalnc materials. Oxford, N. Co.
iDate of Mterial: Mortality : Feeding
application:
Percent

On potted plants, 50 larvae, dilution 1:400 /


1937
August 10


Lead aresnate
2-Acetamldofluorene
p-Iodoxynitrobenzene


Very slight
do
Normal


August 17


4,6-Dinitro-o-cresol 2]
p-Nitrophenyliod.ochloride
Bis(o-aminophenyl) disulfide


On tobacco suckers, 30 larvae, dilution 1:100


1938
September 6


2-Fluorylamine
Zinc mercury thiocyanate
2-Acetaemidofluorene


100
100
90


Very slight
d.o
do


On tobacco suckers, 30 larvae,. dilution 3:200


September 9


2-Fluorylamine
Zinc mercury thiocyanate
2-Acetamidofluorene


On tobacco suckers, 60 larvae, dilution 1:200


September I4


Zinc mercury thiocyanate
2-Aoetamidofluorene
2-Fluorylamine


Y. All dilutions by weight.
2/ Caused severe burning.


do
do


100
87
73


100
95
88





-11-


During 1940 and. 1941 several compounds were diluted with diatomaceous
earth aMd applied. as dusts on fresh tobacco suckers in bottles of water
embedded in soil in 10-inch flowerpots. Each sucker was dusted with 150
mg. of the mixture at a pressure of 14 pounds per square inch, and the
dust was allowed to settle for 2 minutes. The larvae were hatched and
reared on growing tobacco plants in the insectary. In 1941 each material
was tested during each of 8 test periods. Check plants were dusted with
diatomaceous earth, but the mortality vas so low that it can be disregarded.
The results are summarized in table 5.

Table 5.--Mortality of third-Instar tobacco hornworms placed on tobacco
foliage dusted with organio compounds diluted with diatomaceous earth
(1:1)4 Oxford, N. C.
Compound : Replicates : Mortality : Feeding

Number Percent

Tests in 1940, 20 larvae in each replicate

2-Fluorylamine 6 81 Very slight
Diazoaminobenzene 7 76 do
p-Aminoazobenzene hydrochloride 6 66 do
p-Aminoacetanilide 5 8 Normal
1,4-Dinitrosopiperaz ine 5 2 do
Acetone semicarbazone 4 1 do

Tests in 1941, 30 larvae in each replicate

2-Fluorylamine 8 70 Very plight
Diazoaminobenzene 8 58 Sli ght
Phthalonitrile 8 43 Moderate
1,4-Diphenylsemicarbazide 8 41 Slight
p-Aminoazobenzene hydrochloride 8 41 do

Difference required for significance (odds 19:1) 22



The technique was changed slightly in 1942. The bottles containing
the tobacco suckers, instead of being embedded in flowerpots, were simply
placed in the dusting chamber for treatment and then transferred to screen-
cylinder cages for observation. The dusting pressure was increased to 20
pounds per square inch. Both the tobacco hornworm and the tomato hornworm
were used as test insects. The results of the tests made in 1942 and 1943
are summarized in table 6. The high mortality in the check lots of the
tomato hornworm in 1942 is attributed to disease. 2,4-Dinitrophenol
acetate was included in some of the first replicates in 1942, but it
caused such severe burning that it was discarded. Although the different
materials ,were not always tested on the two species at the same time, it
is evident that the tomato hornvorm is easier to kill than the tobacco
hornworm.





- 12 -


Table 6.-Mortality of third-instar hornvorms placed on tobacco suckers
dusted with organic oompoumds diluted with diatonoeous earth (1:1).
Oxford. N. C.

Material : Mortality: Feeding

Percent

30 tobacco hornwvorms in each of 6 replicates, 1942


2-Fluorylamine
Pbthalonitrile
2,4-Dimetbyl-3-pentanone semicarbazone
N-phenyl-N-nitrosobenzylamnine
2-Furaldehyde semioarbazone
Check
Difference required for significance
(odds 19:1)


Very slight
Moderate
Normal
do
do
do


30 tomato hcrnworms in each of 8 replicates, 1942


2-Fluorylamine
Phthalonitrile
2-4-Dimethyl-3-pentanone semicarbazone
N-phenyl -N-nitrosobenzylamine
2-Furaldehyde semicarbazone
Check
Difference required for significance
(odds 19:1)


Very slight
Moderate
Normal
do
do


40 tobacco horwmrorms in each of 6 replicates, 1943


Cryolite
Phthalonitrile
p-Aminoazobenzene hydrochloride
p-Aminoazobenzene
Diazoaminobenzene
Difference required for significance
(odds 19:1)


Slight
Moderate
Slight
do
Moderate


40 tomato hornworms in each of 4 replicates, 1943


p-Aminoazobenzene hydrochloride
p -Aminoazobenzene
Cryolite
Diazoaminobenzene
Phthalonitrile
Difference required for significance
(odds 19:1)


Very slight
do
Slight
do
Moderate





13 -

Tests at Quincy, Fla., 1929-1943 ./


In the tests at Quincy, Fla., second.- or third-instar tobacco
hornworms were placed on caged tobacco plants growing in an open field,
10 hornworms to each plant. The plants produced the cigar-binder or
the cigar-wrapper type of tobacco. The cages had waterproof tops.
After the larvae had become established on the plants, the test materials
vere applied to the foliage, either as water sprays or as dusts mixed.
with talc, at the rate of approximately 15 to 20 pounds per acre. The
sprays were applied with a hand sprayer and the dusts with a puff-
type duster. Since the mixtures with talc could not be applied evenly
with this duster, 15 percent of filter dust was added. Mortality
records were taken after 2 and 5 days.

In preliminary cage tests the following materials did not cause
appreciable mortality of the tobacco hornworm and were not considered
worthy of further trials:


Ammonia (26 percent)
Aluminum acetate
Aluminum hydroxide
Aluminum lactate
Aluminum oxalate
Aluminum sodium sulfate
Aluminum sulfide
Aluminum tartrate
Barium acetate
Barium borate
Barium carbonate
Barium oxalate
Barium manganate
Barium sulfate
Barium sulfide
Barium sulfite
Barium thiosulfate
Bismuth oxalate
Bismuth salicylate
Cascara sagrada extract, powder
Calcium carbonate
Calcium tartrate
Calcium fluoride
Chromium oxalate
Cobaltic oxide
Citric acid, powder
Cupric silicate
Cupric tartrate


Copper potassium ferrocyanide
Cuprous oxide, red
Cupric oxide
Ferric oxide
Ferric salicylate
Ferric format
Ferric tartrate
Manganese carbonate
Manganese sulfate
Manganese sulfide
Magnesium carbonate
Magnesium fluoride
Magnesium oxalate
Magnesium sulfate
Magnesium sulfite
Nickelous tartrate
Strontium bromide
Strontium carbonate
Strontium format
Strontium lactate
Strontium oxide
Strontium oxalate
Strontium phosphate
Strontium sulfide
Strontium fluoride
Zinc carbonate
Zinc sulfide


Y/A.H.Ka den assisted in these studies.




- 14 -


African ginger (Zingiber officinale), root
Alkanet (Alkanna tinctoria) root
Angostura (Gelipea cusparia), bark
Arnica (Arnica montana), root
Belladonna Atropa belladonna), leaves
Buchu (Barosma serratifolia), leaves
Canella Tclanla winterana), bark
Choke cherry (Prunus virginana), bark
Digitalis (Digitalis purpurea,, leaves
Eucalyptus (Eucalyptus globulus), leaves
Liverwort (Hepatica hepatica), leaves
Pokeberry (h tolacca americana), root
Prickly-ash( Xanthoxylum americanum), bark
Red aquill (Urginea maritime), root
Rhubarb (Rheum officinale) root
Senna (Cassia sp.), leaves
Simaruba (SiTaruba sp.), bark
Soapbarktree (Quillaja saponaria), bark
Stramonium (Datura stramonium), leaves
Yellow Jessamine (Gelsemium sempervirens), root


In preliminary tests tartar emetic and clay (1:6) caused some in-
jury to cigar-wrapper tobacco leaves, and the diluted material was
definitely less toxic to tobacco hornworms than lead arsenate diluted
with tobacco dust (1:1).

The following materials were moderately toxic to the insect in
limited cage tests and may possibly be worthy of further trials;
Aluminum fluoride, antimony trioxide, barium fluoride, copper stearate,
cupric borate, cupric citrate, cupric carbonate, cupric oxalate, cuprous
thiocyanate, dandelion (Taraxacum officinale) root, lithium fluoride,
strontium sulfate, zinc cyanide, zinc fluoride, and zinc sulfate.

The toxic action of phenothiazine and lead arsenate against tobacco
hornworms was determined in cage tests. The material were applied in
spray form at three concentrations. The results shown in table 7 in-
dicate that the phenothiazine was definitely less toxic than lead arsenate.

Table 7.--Mortality of tobacco hornworms sprayed with three strengths of
phenothiazine and lead arsenate. Quinov, Fla., 1935.......
Strength Larvae : ,Mortality,...
of spray used : After 2 days: After 5 days

Percent Number Percent Percent

Phenothiazine 0.25 100 50 76
.50 100 48 84
1.00 100 60 90

Lead arsenate .25 30 77 97
.50 20 .85 100
1.00 40 100 100
Check (none) -- 100 1 3





- 15 -


In another series of tests phenothizaine diluted with filter Ilst
(1:10) was dusted on replicated plots in two fields cf 3i7ar-ff-_ tobacco.
The treatments were discontinued prior to harvesting because infestations
on these plots had reached such serious proportions that control. was
obviously unsatisfactory. TAe material caused some burning and bleaching
of the tobacco leaves.

Three homologs of paris green--cottonseed-oil green, aoybeL.-.ll
green, and copper stearoarsenifte (also called stearic green)-- received
from the Division of Insecticide Investigations, wiere tested as T^a-"s
against third-instar tobacco hornworms. To make up water suspensions
it was necessary to add a spreading agent. Diphen.ylbutyl cuAilum s..:
was accordingly used with all the materials and controlB at a streangt
of 0.1 percent. The results, as shown in table 8, inlicatte that tne
soybean-oil green was the most toxic of the three honr-logB-s A ;-Is jeern,
but that it was somewhat less toxic than paris green or lead arsenate.
In foliage-injury tests on shade-grown, cigLr-wrappei: tobacco, the three
homologs caused less burning than did commercial parl reen, t ehe
might be classified as dangerous on this crop.


Table 8.--Toxlcity of hornologs of paris green to the t.:bscco hcr.w=rm
when applied as sprays on potted plants ; 50 larvae In -- test.
Quincy, Fla., 1936

Compound : Strength of weter : ._____ ,_ _ .
s,.isgension : --- - -
Percent Percent Pcent

Soybean-oil green 0.05 10 -
Cottonseed-oil green .05 12 -
Checks (none) --- 6 12

Soybean-oil green .075 18
Copper stepxroarsenite .075 2
Checks --- 4 8

Soybean-oil green .075 32'
Lead arsenate .075 ,
Checks ----- 10

Soybean-oil green .075 2 c, /
Paris green .075 701C.
Checks ---2 12


Y_ Mortality after 4 days; the


Jestrooel by accident.


test plants were then





- 16 -


In 1941 four synthetic organic compounds that hbad. shown promise
against other insects were tested., both as sprays at a dilution of 1:400
(by weight) and. as dusts nixed with talc (1:1), against third.-instar
hwoarms. As indicated in table 9, when applied as sprays phthalonitrile,
p-aminoazobenzene, and 1,4-diphenylsemicarbazide showed some toxicity
but were much less effective than lead. arsenate; as dusts all four com-
pounds were toxic, but the action was much slower than that of lead.
arsenate. Phthalonitrile was the most toxic dust, but p-amlnoazobenzene
was very repellent and appeared to exert sme contact action.


Table 9.--Mortality of third.-instar tobacco hornworms feeding on tobacco
plants sprayed or dusted with several organic compounds; 50 larvae in
each test. Qaincy, Fla., 1941

Material Sprays : Dusts
-In 2 days:In 5 days:In 2 days: In 5 days

Percent Percent Percent Percent

Phthalonitrile 12 30 70 94
p-Aminoazobenzene hydrochloride 4 30 44 81
1, 4-Diphenylseamicarbazide 22 76 32 86
p-Aminoacetanilide 2 2 12 61
Lead, arsenate 100 100 100 100
Check 0 0 0 0


.n_ preliminary cage tests antimony trisulfide, cuprous cyanide, and
DDT 4/ were sufficiently toxic to the second and third instars of the
tobacco honrworm to be worthy of critical experiments.




F. S. Chamberlin. Cage tests with DDT against certain insects
affecting tobacco. (Scientific Rote) Jour. Econ. Ent. 37:148. 1944.
In more recent laboratory tests by Stahl a 10-percent DIT dust killed
100 percent of third-and fifth-lnstar tomato hornworms within 24 hours,
but only 24 percent of third.-istar tobacco hornworms, and was in-
effective against the latter species in a field experiment at Oxford.
According to an unpublished report by Norman Allen this dust was in-
effective against the tobacco hornworm in field experiments at Florence,
S. C., in 1944.




- 17 -


Tests at Clarksville, Tenn., 1937

The following promising new materials were furnished by the Division
of Inseotioide Investigations in 1937 for testing against hornworns on
tobaooo at Clarksville, Tenn.:


Benzopinaool
p-Bromobenzonitrile
N- (o-Car'boxyphenyl)glyoine
Dibenzodioxin
3, -Dichloroaoetophenone
p-omega-Diohloroaoetophenone
3, 5-Dinitrophenoxazine
Glycoine
Hexamethylenetetramine
Hydrobenzamid.e
p-.ydroxyaoetophenone
Iodosobenzene
Iodoxybenzene


p-Ni trodiphenyl ether
Pentaerythritol
Phenazlne
Phenoxazlne
N-Phenylglyoine
1,2,3, 4-Tetrahydroaoridone
Thiobarbiturio aoid.
Thiosalioylio acid
3, 4-cmega-Trichloroaoetophenone
Trithionethylene


These materials were applied as sprays on field-grown plants of
dark fire-cured tobacco. Both tobacco and tomato hornworms were present.

The materials that were not soluble in water were first dissolved
in acetone, sufficient water being added later to make 1 pint. Heavy
precipitates formed in some of the solutions, and these were expelled
when the sprays were applied. Each preparation contained 0.42 percent
of the test material and. was applied to a single plant with a quart-size
atomizer until the leaves were dripping wet. Hornworms of various sizes,
collected from field-grown tobacco, were placed on the treated plants
immdiately after they had been sprayed, 18 or 20 on each plant. Thd
plants were then covered with screen cages. Only two of the materials
gave over 10 percent mortality, phenazine 30 percent in 2 days and
benzopinacol 20 percent in 3 days. Slight to moderate burning was caused
by thiobarbituric acid, p-hydroxyacetophenone, 3, 4-om6ga-trichlorocetophenone,
and p-omega-dichloroacetophenone, and severe burning by rhen.zine.

Tests were also made with powdered roots of mayapple (Pod,-'.. llum
peltatum) and. pokeberry, each applied as a dust and as a spray, l. t
neither material was even slightly effective.





UNIVERSITY OF FLORDA


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