Prospects for Nonchemical Insect ControlAn Industrial Viewl
By Roy HANSBERRY
Biological Sciences Research Center,
Shell Development Company,
Modesto, California
To further establish a numerical basis for the
diminution of chemical insecticide research,
shows the distribution of programmed papers
annual meetings of the Entomological Society of
in 1957, 1962, and 1967.
Public concern over pesticides in the environment has
stimulated research toward controlting insects without
insecticides. This attitude has given much-needed impetus
to ecological entomology, and industry has no quarrel
with such research. However, few people realize the extent to which tax-supported work on proper use of insecticides has diminished. This drying up of insecticide
research in experiment stations has happened while the
use of insecticides has been increasing at about nine percent a year. This fact does concern industry and should
concern farmers, research administrators, and the general
public. The once strong position of leadership of the
United States Department of Agriculture and the State
agricultural experiment stations in advising farmers how
to use insecticides has for the most part been abdicated.
Industry has largely assumed this responsibility.
This
mayor may not be in the public interest.
The trend away from research
due to several factors:
Note that Section F no longer has the apparently
opprobrious appellation "Chemical Contro1." At last
year's meeting there were only 14 papers in which observations were made on effectiveness of insecticides applied
to field, greenhouse, or stored crops. This figure compares with 32 papers in 1962 and 52 in 1957. Put another
way, ten years ago 24% of the papers dealt with chemical
control of insects in the field. By 1962 the percentage had
dropped to 10%. Last year only 14 out of 397 papers, or
3.5%, dealt with control of crop insects with conventional insecticides.
While fewer and fewer programmed papers at the Entomological Society of America annual meetings dealt
with chemical control of crop pests, the use of insecticides
and number of entomologists were both increasing. Fig.
I shows these trends graphically.
The average annual
increment in insecticide sales has been 9% a year" and in
ESA membership 3.8% a year.
on insecticide usage is
1. Public concern over pesticides in the ecosystem.
2. Congressional pressure to reduce the use of chemical
insecticides in conformity
with President
Kennedy's
mandate to implement the recommendation of his Science
Advisory Committee Report on The Use of Pesticides
(Wiesner 1963).
3. A drive to gain status by "upgrading"
stations to Centers for Basic Research.
apparent
Table 2
for the
America
California, like other States, does do work on chemical
control, and many fine scientists are involved. The work
is published in the form of annual spray recommendations
which are used in grower meetings and to support the
Agricultural
Extension
Service.
Informational
news
stories in agricultural
trade journals also are issued.
Such research no longer has the status it once held. It
certainly is no freeway to tenure at $20,000 a year, and
for young assistant professors is not even a wholly negotiable security against perishing.
experiment
4. Frustration of many field entomologists with a flood
of new products and formulations, frequently differing
little from existing products, sometimes never subsequently made commercially available, and vulnerable to
early development of resistance by the target pest.
These, and other factors, have combined to provide
widespread public support for any project which offers to
view conventional insecticides with alarm, or to control
pests by esoteric methods.
Yet this is just exactly the kind of research that has
made the United States citizen the best fed person in the
world, and it is just exactly the kind of research we need
to keep food production even with people production.
The trend away from chemical control research began
before the 1962 publication of Silellt Sprillg. E. F. Knipling's dramatic demonstration of the sterile-male technique in 1955 to eradicate the screw-worm on Curacao
was certainly a major factor. Table 1 shows how research emphasis in USDA's Entomology Research Division has changed from 1955 to 1967.
The previous discussion deals with plant protection in
the United States. I think it is less true of animal protection. I am confident it is hardly applicable outside the
United States. I am sure it applies not at all to weed
control, fertilizer usage, plant breeding, agricultural engineering, or any other important aspect of applied agriculture.
Dr. Knipling points out that during the period 1957-67
the scientific manpower in his division probably doubled
and thus the amount of effort on conventional insecticides
has not decreased as much as the percentage would
indicate.
This de-emphasis of chemical control research can be
justified only if there are real prospects for success by indirect control methods even where noninsecticidal chemicals are used. Otherwise agriculture and the public are
PROSPECTS
1 Paper presented at the annual meeting of the Pacific Branch,
Entomological Society of America, State Line, Nevada, June 25,
1968. Published as a maller of record without intention to imply
subscription to the ideas expressed eitber by tbe editors or the
"flic('rsof tbe EntomologicalSocietyof America.
FOR NON CHEMICAL
CONTROL
"Estimates supplied by Shel1 Chemical Co., Agricultural
Chemicals Division. Adopted largely from Annual Pesticide Re·
view. Agricultural Stabilization nnd Conservation Service. U. S.
Department of Agriculture.
229
o---a
Table I.-Estimates
of relative effort in the Entomology Research Division. 1955-67.·
300
Membership
It--X
Popers
Percentage of total effort
Area of research
Conventional insecticides
Biological and specific
chemical methods
Fundamental entomology
a Kniping
1955
1957
1962
1967
66
60
32
21
17
17
21
19
35
33
42
37
U.S. Soles of Insecticides
0---0
in ESA
on Chemicol
Control
200
1967.
,...
It)
being badly served. I now propose to show that prospects
for non chemical control of agricultural insect pests are
too dim to justify the wholesale abandonmont of chemical-control research.
Opinions on prospects for success in research projects
generally come from within and are frequently made to
appear as optimistic as possible to obtain or retain support for the work. I believe such wishful thinking is
~
0
c:
••~
..
Cl.
x/ \
of insects.
About 85,000 species of insects have been described
from the United States and Canada. Only about 1,425
of these have common names approved by the Entomological Society of America (Blickenstaff 1965) as insect
pests. The other 83,575 species are not pests, or attack
our goods, persons, useful animals or crops only very
rarely. This is because most animals and plants are resistant to most insects and all insects are subject to a
Table 2.-Programmed
1962, and 1967.
papers, ESA meetings in 1957,
B
Ca
Cb
Cc
Cd
C
D
E
F
General entomology
Systematics, morphology and
evolution
Physiology and toxicology
Physiology, biochemistry and
toxicology
Biological control
Apiculture
Relation of insects to plant disease
Ecology and bionomics
Ecology, behavior and bionomics
Medical and veterinary entomology
Control, extension and
regulatory entomology
Extension and regulatory
entomology
Chemical control
Crop protection entomology
Total papers presented
X
x
"-x
X
""-
\
X
\
X
X
o
1957
1963
1961
1959
1965
1967
Yeor
FIG. I.-Eleven
year trends in insecticides sold, membership in ESA and papers on chemical control of crop
insects at Annual ESA Meetings.
natural struggle for existence that limits their numbers.
This is natural biological control and it must never be
confused with managed biological control.
DeBach's book (1964) on biological control lists all the
successful cases on record of managed biological control.
Only 106 insects are listed from anywhere in the world
that have been partially, substantially, or completely controlled by parasites or predators introduced into an area
by man. Sixty-one species of insects are reported to have
been more or less controlled by biological methods in
Canada and the United States. Tables 3 and 4 show
these cases.
Six of the nine Canadian cases are from British Columbia. Table 4 illustrates a fundamental characteristic of
biological control. It is most likely to be effective on
islands, either geographic or ecological. Forty-five other
species of insects have been controlled in 87 other countries. Of these 59, or 68%, are from true islands. Most
of the other cases are from ecological islands such as
parts of Australia, Israel, or Chile. Except for control
of the cottony-cushion scale in Spain and Portugal and
partial control of the woolly apple aphid in Germany and
Section and Category
A
j.<
x
especially true of much research toward indirect control
Biological COlltrol.-Although
the idea of using parasites and predators to control insect pests is as old as
economic entomology, the first importation of an arthropod for biological control dates only from 1873, when a
predaceous mite was imported from America to control
the grape leafhopper in France. Not until 1888, when the
vedalia was brought to California from Australia to control the cottony-cushion scale, was the technique completely successful. This dramatic success, which probably literally saved the California citrus industry, has not
been equalled in the subsequent 80 years.
I
100
Table 3.-Numbers
of cases for which some degree of
biological control is claimed.
17
65
Hawaii
California
Rest of
U.S.
2
6
1
11
10
1
8
8
2
8
3
1
62
43
212
Canada
319
Partial control
Substantial control
Complete control
397
230
Table 4.-Species
control is claimed.
Pest Species
Homoptera
California red scale
Yel10w scale
Cottony-cushion scale
Purple scale
Fig scale
Oystershel1 scale
Olive scale
Coconut scale
San Jose scale
European fruit lecanium
Black scale
Nigra scale
Avocado mealybug
Lebbek mealybug
Citrus mealybug
Long-tailed mealybug
Comstock mealybug
Citrophilus mealybug
Pink sugarcane
mcalybug
Apple mealybug
Sugarcane aphid
Walnut aphid
Spotted alfalfa aphid
Pea aphid
Sugarcane leafhopper
Taro leafhopper
Torpedo bug
planthopper
Lepidoptera
Sweetpotato leaf miner
Asiatic rice borer
Armyworm
Oriental moth
Sugarcane borer
Oriental fruit moth
Western grape leaf
skeletonizer
N utgrass armyworm
Brown-tail moth
Gypsy moth
European corn borer
Nantucket pine tip moth
Satin moth
Larch casebearer
Pea moth
Coleoptera
Chinese rOse beetle
Oriental beetle
Asparagus beetle
Elm leaf beetle
Alfalfa weevil
Japanese beetle
New Guinea sugarcane
weevil
Fern weevil
Diptera
Melon fly
Oriental fruit fly
Mediterranean fruit fly
Holly leaf miner
Orthoptera
African mole cricket
Chinese grasshopper
American cockroach
Dermaptera
European earwig
Table 4.-(Continued.)
for which some degn:t: of biological
Area
California
California
California
California-Texas
California
British Columbia
California
Hawaii
California
British Columbia
California
California
Hawaii
Hawaii
California-Hawaii
California
Eastern United States
California
Hawaii
British Columbia
Hawaii
California
California
California
Hawaii
Hawaii
Degree of
Control&
P
S
C
P-S
P
P
S
S
P
S
S
S
S
P
P
P
C
C
S
C
S
P
S
S
C
S
Hawaii
S
Hawaii
Hawaii
Hawaii
Massachusetts
Florida
U.S. (except
New Jersey)
P
P
P
S
P
P
California
Hawaii
Northwestern U.S.
New England
United States
Nebraska
U.S.-British Columbia
Canada
British Columbia
S
P
S
P
P
P
S
S
S
Hawaii
Hawaii
Washington
California
California-Utah
Eastern United States
P
S
P
P
S
P
Hawaii
Hawaii
S
P
Hawaii
Hawaii
Hawaii
British Columbia
P
S
P
P
Hawaii
Hawaii
Hawaii
P
S
P
WashingtonBritish Columbia
P
Pest Species
Hymenoptera
European wheat stem
sawfly
European spruce sawfly
Larch sawfly
•P
control.
= partial
Degree of
Control&
Area
control,
S
S
S
Ontario
Canada
British Columbia
S
= substantial
control,
Poland no case is reported from Western
the whole idea began 200 years ago.
C
= complete
Europe where
Among the 61 cases in Tables 3 and 4, eight are of so
little importance that the pests have not been given common names. Claim for biological control of such species
as European COrn borer, American cockroach, armyworm.
alfalfa weevil, elm leaf beetle, European earwig, gypsy
moth, and pea aphid have not removed them from the list
of pests for which large volumes of chemical insecticides
still have to be used.
In some instances it seems probable that the introduced
species is credited with the natural biotic resistance that
invariably follows the introduction of a pest species.
The successes, whether partial or complete, have been
of tremendous value to agriculture and well illustrate
the potential for this kind of research. However, only 4%
of the species listed by Blickenstaff (1965) have been
controlled in any degree after 80 years of U.S. work. As
DeBach (1964) points out, successful biological control,
in addition to being strongly related to island ecology,
generally requires the target insect be a pest of perennial
instead of annual crops. Therefore, it seems very unlikely that we can ever expect biological methods to contrel field and truck-crop pests, nor can we expect many
more successes with the common cosmopolitan pests of
such widely grown orchard crops as apples and peaches.
Even partial control of as few as 10% of our pest species
is probably unobtainable with another 50 years of intensive research.
Microbial Control.-It
was shown by Dutky (1941)
that two species of bacteria causing a "milky disease"
could be used to control the Japanese beetle in the Eastern United States. Because the bacteria can so far be
readily grown only on living larvae, the cost of spore
production has remained too high for a commercially
viable business to develop. Although the disease persists
in soil, the decline in seriousness of the Japanese beetle
in the Eastern United States is probably due to insecticides and a variety of ecological pressures rather than to
a permanent effect of milky disease.
The research and teaching of Steinhaus (1963) has
stimulated many efforts to control insects with bacteria,
fungi, viruses, protozoans, and even nematodes. With
the marginal exception of Bacillus thuringcnsis none of
these has reached commercial success, principally because
the many problems of axenic culture have never been
solved for insect pathogens.
Bacillus tllllringcnsis has been produced and used commerically for about ten years. It would be inappropriate
for me to speculate on the commercial success of the program, so let me quote some of the limitations as reported
by others. The living spores and their contained poly-
------ .... --
231
peptide toxin are extremely effective against numerous
lepidopterous larvae. However, they are specific and do
not control the aphids, mites, plant bugs, and other pests
commonly controlled by other insecticides. B. thuringens1s
does not persist in the field, so applications have to be
made as frequently as with conventional insecticides.
Farmers like to see a quick knockdown of pests, and this
does not occur with any of the microbial insecticides.
The fermentation, concentration, and formulation procedures involved in manufacture would seem to be no less
costly and difficult than chemical synthesis on a comparable scale. The Food and Drug Administration
has
taken a normal critical attitude toward the use of bacteria
and their contained toxins, and especially toward the use
of viruses, on food crops. Thus no advantage seems to
reside in microbial pesticides with reference to mammalian safety.
The polyhedrosis viruses attack many species of insects
but recently have demonstrated
(Ignoffo 1967) highly
effective control of the bollworm. Against this insect,
control is obtained with 100-1000 larval units per acre.
The virus can so far be produced only from other larvae,
50 it would seem that 10,000 to 100,000 larvae
must be
collected or raised for every spray for every 100-acre
ficld. Without axenic culture methods the process is
hopelessly uneconomic. As with other microbial pesticides
the viruses are specific and conventional insecticides
would still have to be used for weevils, aphids, mites,
thrips, etc.
In summary, the microbial pesticides have not demonstrated superiority over chemicals, and they have inherent disadvantages which are absent in many of the new
pesticide chemicals.
Sterile-Male
Techniques.-Radiation-sterilization
techniques as a means of control or eradication were conceived by Knipling 30 years ago but first reduced to practice in 1955 with the eradication of the screw-worm in
Curacao (LaChance et al. 1967). Since then the screwworm has been eradicated in Florida, Texas, and the
Southwest, but migration from Mexico requires a continuing program. Two other successful eradications have
been reported, the oriental fruit fly on Guam and the
melon fiy on Rota. Eleven other attempts to eradicate
five different species of fruit flies have failed, even though
small islands or isolated areas were used for tests. Thirteen other field tests with eight species of insects have
all failed of eradication for various good reasons. However, in nearly every case, drastic reductions in field
populations resulted from the eradication attempts, so
the technique is still considered highly promising for
selected insects.
The high cost and logistics involved with laboratory
rearing of insects, their exposure to a Cobalt-60 source,
transportation to and distribution in possibly remote areas
is a formidable task. The technique is known to be effective only in areas of low population density. To use it
on high populations such as boll weevil, massive spray
programs would be needed to reduce the wild populations,
or many times the 50 million screw-worms needed per
week would have to be reared, sterilized and transported.
ing agents, radiomimetic, mutagenic, carcinogenic, or
teratogenic. The Food and Drug Administration has approved no such materials for commercial use.
For sterile-male teclmiques to be effective the approach
must be made over the whole ecological unit whether it
be a valley, a county, or a continent. Such a program
can be imposed only by a government and hence offers
little commercial incentive to private initiative. If the
campaign involves mass spraying, intensive objectiom
from the nonagricultural public must be anticipated. The
multimillion dollar appropriations may be hard to pry
out of Congress and could not be depended on over the
five- to ten-year period which such a program might
require. If a private company developed an effective
chemosterilant it would have no market to individual
farmers who are interested only in a quick kill of the
present generation.
A massive government
program
would provide the only likely market for a chemosterilant.
We must conclude again that this approach to insect
control, although stimulating scientifically, is not likely
to have much impact on insecticide usage during the next
quarter of a century.
Electromagnetic Encrgy.-Many
forms of electromagnetic energy have been tried for controlling or killing
insects. The generators have always been a problem,
since electricity is generally required, and the installations become too expensive for field use on a large scale.
Stuart Nelson (1967) of the USDA Agricultural Engineering Research Division, Lincoln, Nebraska, has reviewed the subject in Kilgore and Doutt's book, Pl'st
COlltrol-Biological,
Ph}'s1Cal and Selected
Chemical
ilfethods. He finds little practical application for any of
the various forms of radio-frequencies, infrared radiation,
visible and ultraviolet light, or ionizing radiation.
Light traps have been widely used and will catch many
moths. Their value as a means of timing moth emergence
as a guide to timing of sprays is unquestioned. Some recent experiments have indicated some degree of control,
but generally in combination with other techniques such
as post-season stalk cutting in tobacco or with sex attractants in cabbage looper. It appears that under highly
specialized circumstances light traps are a useful adj unct
to chemical control. Against household or stored-products
insects lights may have a special place, but we are concerned here mainly with prospects for replacing chemical
insecticides in the field.
Hormones aud Pherolllou£'s.-The
persistant publicity
given juvenile and molting hormones obscures the fact
that at least another dozen insect hormones are known,
some of which may be far more important.
A whole
series of endocrine materials have been found which regulate gut activity, blood sugar, diapause, egg development,
integument tanning, and many other aspects of body
chemistry. Most of these are produced by the action of
neurosecretory
substances from a group of brain or
ganglion cells, which substances cause special glands in
the thorax or along the gut to produce the hormones.
Since the identification and synthesis of the natural
juvenile hormone and the molting hormone, ecdysone,
numerous active related compounds have been found.
Several farnesol derivatives related to the juvenile hormone have now been synthesized.
Some of these are
reported to be up to 40 times as active as the natural
material. Field tests of such materials are planned for
this summer. An amazing number of "phyto-ecdysoncs"
This seemingly insurmountable
difficulty has led to
proposals and research toward chemical sterilization in
the field. The chemistry and biological effects of chemosterilants have been discussed at length by Borkovec
(1966). After years of search no suitable compounds
have been found. Chemosterilants are likely to be alkylat-
232
expect a wave propagation effect whicb is possible with
parasites or sterile males.
The physiological pathology of insects has been reviewed by Martignoni (1964). Many diseases and abnormal conditions not caused by microorganisms or parasites are described, and the following statement is made
"the study of functional lesions will undoubtedly lead to
the discovery of particularly weak links in some metabolic
cycles. The construction of antimetabolites is the next
alluring step for the toxicologist. Phylar or subphylar
differences in metabolic pathways would enhance the
probability of finding anti metabolites with no potency for
vertebrates."
Imidazole, an antimetabolite of histamine
and nicotinic acid, has been proposed (Pence 1963) to
protect fabric from insect attack. The proposal never became commercial and I am not aware of its extension to
control of crop insects. However, personal discussion
with Dr. Pence indicates that he is not at all optimistic
about imidazole or other antimetabolites as a practical
means of insect control. Such antimetabolites, after all,
are simply novel forms of chemical insecticides. Phosphate insecticides are antimetabolites of acetyl choline.
ban' bel'n isolated from plants, and nc\\" materials of this
trJll~ are being found whenever they are sought. I consider the rcsearch on chemistry and synthesis of these
two insect hormones to be the most promising of all lines
of noninsecticidal research. Yet one must consider that if
S\ll,l't'ssful comJlounds of this type are developed they will
he, in fact, a kind of synthetic chemical insecticide with
tbe same kinds of problems as are faced with the 2,4-0
berhicides. It is hard to speculate on the future of this
line of research until the first successful field tests are
reported. They may well be advantages or disadvantages
that have not appeared in the laboratory studies made to
date.
The possibilities involved are suggested by an announcement (Bowers and Blickenstaff 1966) that the diapause of alfalfa weevil can be broken with a synthetic
juvenile
gonadotropic
hormone,
1O,1l-epoxyfarnesenic
acid methyl ester. This could have great economic value
if such a synthetic hormone mimic could be used in a
post-harvest spray of cotton or alfalfa to prevent the
overwintering of boll weevil or alfalfa weevil. Fall application of insecticides has proved effective against these
species, but the chlorinated hydrocarbons leave illegal
residues on spring crops of alfalfa and the ultra-Iow\'olume sprays of malathion used against the boll weevil
may not be the ultimate in cost effectiveness.
Pheromones are like hormones in that they are glandular in origin and act in minute amounts. They differ in
that they act outside the body, i.e., they are produced by
one individual and act on another. They exercise control over colonial insects in the form of clustering attractants, trail substances, or alarm signals. They are
presently most notorious as sex attractants.
Hopes have:'
often been expressed that they could be used as baits
with chemosterilants or as flooding agents to prevent
males from locating females. Field trials so far have all
failed for various reasons. The most recent attempt
(Hoffmann 1968) was use of the sex attraetant, cis-7dodeccn-l-ol acetate, of the cabbage looper, in an attempt
to control the looper on cotton and lettuce in the isolated
Red Rock area of Arizona. Blacklight traps were used
in conjunction with the pheromone. Although the nearest
plantings to the experimental area were 8-10 miles away,
and tremendous numbers of looper moths were caught in
tbe baited light traps, oviposition was not eliminated in
tbe treated area.
.
As with the true hormones, effects are specific. However, while the true hormones are complex compounds,
some of which are steroids, most pheromones are relatively simple. Chemists have synthesized such compounds
for screening and testing. Stereoisomerism at a double
bond is usually important in their activity. However, it is
possible that inactive isomers would be no more than
diluents, and since the active isomers are so potent, mixtures of isomers could still be commerically feasible.
Crop Resistance to Insect Attack.-By
far the most
successful method of nonchemical control of insects has
been selection and development of resistant crop varieties.
It is relatively easy to select and propagate a few surviving plants in a pest-ravaged field. A process of natural
selection of insect and disease-tolerant strains is going on
continually. Because the plant breeders do not always
publish their successes, they frequently are not given
credit for their contributions. 'When the alfalfa aphid hit
California numerous species of parasites and fungi were
liberated, a few of which became established. Within a
three-year period of their releases, nearly all tbe aphidsusceptible common varieties of alfalfa were replaced
with Lahontan and Moapa, varieties selected, introduced,
and established primarily because of their resistance to
nematode and aphid attack. The fact that spotted alfalfa
aphid is no longer a problem in the San Joaquin Valley
is probably more due to the resistant varieties than to
managed biological control.
It is my belief that resistant varieties have been the
most successful of all attempts to limit insect damage
without spraying, and that resistant varieties offer the
greatest hope for the future of nonchemical pest control.
However, this may be an almost endless process for, as
as has been demonstrated in plant pathology, organisms,
including insects, can acquire resistance to nonchemical
as well as chemical control measures. Any time man
applies a pressure that comes close to exterminating an
organism adaptations in the direction of resistance are
not only possible but perhaps probable.
Resistance can be due to many things. Onions with
wide-angled leaves are little bothered by thrips. Corn
with open ends of ears give no protection to corn earworm. Much of such resistance is probably due to the
presence of a feeding or ovipositing repellent or absence
of an attractant.
Most work on resistance has been done from the standpoint of genetics and crop selection. Most research on
chemical identification of the factors has not been followed up by synthesis and field testing of the compounds.
J uglone has been found (Gilbert et al. 1967) to be an
effective feeding repellant against bark beetles and Klun
et al. (1967) described 2,4-dihydroxy-7-methoxy-l,4benzoxazin-3-one, an active agent in resistance to the
European corn borer.
Gelletic Factors alld Alltimctabolites.-It
has been sugg'ested that among the many mutations found in insects
some would be disadvantageous to the species and could
be propagated for release to breed with and destroy the
wild population. Results of such a test on mosquitoes have
recently been reported by Laven (1967). Deposition of
fertile eggs was stopped in a limited area in Burma, but
the experiment was not continued long enough to determine whether eradication had actually occurred. Release
of insects with cytoplasmic incompatibility, or carrying
any gene which was inimical of the wild population,
would seem to be self limiting. Certainly one could not
233
There was considerable interest aroused in synthetic
antifeeding agents when American Cyanamid announced
(Wright
1%3) the discovery of 4'-(dimethyltriazeno)
acetanilide, an effective antifeeding agent for most leafchewing insects. However, four years after he announced
the discovery Wright (1967) stated that efforts to find a
commercially successful antifeedant have been to no avail.
oratory and field aspects of chemical control, good control
was always obtained with one or more chemicals. Surprisingly, only 34 experiments reported successful control
of insects on food crops, a1\ with insecticides.
Are we fulfilling our real functions as entomologists
if the 5900 of us can give our JOURNALonly 34 papers in
a year which demonstrate our present ability to increase
the world's food supply?
Repellents.-While
no chemical repellent will ever
equal the aluminum screen for effectiveness and persistence there is a substantial market for insect repellents.
The'market
is not large at the manufacturer's level, but
the military, sportsmen, and livestock growers buy ~onsiderable amounts of formulated products. The obvIous
disadvantages of chemical repellents make them unlikely
to be effective for protection of field crops. They are
specific, and since they do not kill pests, can do no more
than protect small plots surrounded by alternate food
sources for the pests. To be effective they must be
somewhat volatile, and hence nonpersistent.
Reflecting
foil, or heavy applications of black or white powder are
Beirne (1967) writes: "Studies that are based on controls require improvement in two ways. One is to find
new and improved existing agents and procedure. Here
the most important thing is to find fugitive and pestselective chemical pesticides. The other is to correct the
present imbalance in amount of research on chemical control as compared with that on nonchemical ones." I disagree with both statements. First, we need insecticides
that are new, safe, persistent, and economical, not fugitive
and specific. Such materials would multiply the cost to
physical barriers.
agriculture by several times. Second, the foregoing analy-
Their cost limits their usefulness.
Integrated C ontrol.- The phrase has been defined by
Smith and van den Bosch (1967) as "a pest population
management system that utilizes all suitable techniques
either to reduce pest populations and maintain them at
levels below those causing economic injury or to so
manipulate
the populations
that they are prevented
from causing such injury. Integrated control achieves
this ideal by harmonizing techniques in an organized way,
by making the techniques compatible, and by blending
them into a multifaceted, flexible system." This rather
verbose statement, I interpret to mean: Sometimes it
takes more than one method to control insects. The same
objective reasoning should dictate using heavy and frequent insecticidal sprays when they are safe and economical as we1\ as not using certain insecticides if they leave
illegal residues or ki1\ beneficial insects or wildlife.
In other words, to me integrated control is just good
entomology, and common sense dictates the use of insecticides in most serious insect-control programs. The regularly increasing use of insecticides in the face of public
resistance as shown in Fig. 1 graphically illustrates this
point. Use of resistant varieties, noninference with natural enemies, attention where possible to the best planting time, and not wasting insecticides is again just good
entomology.
The State of California, where the integrated-control
concept originated, did not hesitate to
jump in with a massive overspraying program when the
pink bo1\ worm threatened our cotton crops.
CONCLUSION
ses of research underway in the publicly supported laboratories show a dangerous reduction in amount of research
on chemical insecticides while their use is being rapidly
expanded. The new chemicals which industry is producing need more research, not less. I do agree with one of
Beirne's statements: "It is logical that the best solution
to any pest problem will be found by identifying and
evaluating all possible controls and then devising the best
combination to use."
If we do exactly that, the pesticide industry has a
prosperous future and we may help defer the coming
world food crisis for a few more years.
REFERENCES
Beirne, B. B. 1967.
London. 123 p.
Pest
CITED
Management.
Leonard
Hill,
Borkovec, A. B. 1966. Insect chemosterilants.
III Advances in Pest Control. Vol. VII. Interscience Publ.
143 p.
Blickenstaff, C. C. 1965. Common Names of Insects
Approved by the Entomological Society of America.
Bull. Entomol. Soc. Amer. 11 (4) : 287-320.
Bowers, W. S., and C. C. Blickenstaff.
1966. Hormonal
termination of diapause in the alfalfa weevil. Science
154: 1673-4.
DeBach, P. (ed.).
1964. Biological Control of Insect
Pests and Weeds. Reinhold Publ. Corp., New York.
844 p.
If we in industry recommend the use of our insecticides
wisely, integrated control will expand rather than diminish their use.
FEW REPORTSOF SUCCESS
It is obvious that most entomologists who do research
on indirect methods of control do so with personal faith
and confidence that worthwhile new methods will be
found. Yet it seems to me that the work has so far been
disastrously
unrewarding.
In the six issues of the
JOURNAL OF ECONOMIC ENTOMOLOGY,June 1967-April
1968, there were 86 papers dealing with control of crop
insects by indirect methods not using conventional insecticides. Some workers found reduced populations of
insects, but not a single case of commercial control was
reported that did not depend primarily on conventional
insecticides. Of the 106 papers dealing with various lab-
234
Dutky, S. R. 1941. Testing the possible value of milky
diseases for control of soil-inhabiting larvae. J. Econ.
Entomol. 34(2) : 217-8.
Gilbert, B. L, J. E. Baker, and D. M. Norris.
1967.
Juglone (5-hydroxy-l,4-naphthoquinone)
from Car)'a
ovata, a deterrent to feeding by Scolytus multistriatus. J. Insect Physio!. 13(10) : 1453-9.
Hoffmann, C. H. 1968. What does the USDA foresee
on policies and procedures of integrated control?
Paper given at Western Agricultural Chemicals Association, Portland, Oregon. January 10, 1968.
Ignoffo, C. M. 1967. The nuclear polyhedrosis viruses
of Heliothis zea (Boddie) and Heliothis virescens
(F.). I. Virus propagation
$cct Patho!. 7(2) : 209-16.
and its virulence.
J. In-
and Richard L. Doutt.]
P. 89-145.
Klun, J. A., C. L. Tipton, and T. A. Brindley.
1967.
2, 4-Dihydroxy-7 -methoxy-1, 4- benzoxazin-3- one
(DIMBOA),
an active agent in the resistance of
maize to the European corn borer. J. Econ. Entomo!.
60(6) : 1529-33.
Knipling, E. F. 1967. Letter
vember 6, 1967.
to Roy Hansberry,
Pence, R. J.
pesticide.
Academic Press, New York.
1963. The antimetabolite,
J. Econ. Entomo!. 56(1):
imidazole as a
1-7.
Smith, R. F., and R. van den Bosch. 1967. Integrated
control.
Chapter 9 in Pest Control-Biological,
Physical and Selected Chemical Methods. [Ed. by
Wendell W. Kilgore and R. L. Doutt.] Academic
Press, New York. P.295-340.
No-
LaChance, L. E., C. H. Schmidt, and R. C. Bushland.
Steinhaus, E. A. 1963. Insect Pathology, an Advanced
1967. Radiation-induced sterilization.
Chapter 4 i,~
Treatise. Academic Press, New York. 2 vols. 661
Pest Control-Biological,
Physical
and Selected
and 689 p.
Chcmical Methods. [Ed. by Wendell W. Kilgore and
Wiesner, J. B. 1963. Report on the use of pesticides.
R L. Doutt.] Academic Press, New York. P. 147-96.
Prepared by the President's Science Advisory ComLaven, H. 1967. Eradication of Culex PiPiens fatigans
mittee Panel on the Use of Pesticides. The White
through cytoplasmic incompatibility.
Nature. 215:
House, May 16, 1963.
382-4.
Wright, D. P., Jr. 1963. Antifeeding compounds for inMartignoni, M. E. 1964. Pathophysiology in the insect.
sect contro!. Advances Chern. Ser. 41: 56-63.
Ann. Rev. Entomo!. 9: 179-206.
1967. Antifeedants.
Chapter 8 in Pest Control-Biological, Physical and Selected Chemical Methods.
Nelson, S. Q. 1967. Electromagnetic
energy. Chapter
[Ed. by Wendell W. Kilgore and Richard L. Doutt.]
3 i,~Pest Control-Biological,
Physical and Selected
Academic Press, New York. P.287-93.
Chemical Methods. [Ed. by Wendell W. Kilgore
PROPOSED ADDITIONS TO THE LIST OF COMMON NAMES OF INSECTS
Approved by the Entomological Society of America
The 1968 Committee on Common
for consideration by the membership.
Names
of Insects has approved 8 new common names. These are presented
HEMIPTERA(HETEROPTERA)
for
NeurocolPus nubilfls (Say)
HEMIPTERA(HOMOPTERA)
for
M acrosiph1l1n scoliopi Essig
LEPIDOPTERA
for
GYPsolloma haimbachiana (Kearfott)
for
Laspeyresia anaranjada Miller
for
Surattlza indentella Kearfott
for
Croesia semipurpuralla (Kearfott)
c10udcd plant bug
western lily aphid
cottonwood twig borer
slash pine seedworm
buffalograss webworm
scarlet oak leaf tier
-Qll
-QQ2
-U33
-U33
-U41
-U49
COLEOPTERA
PacllJ1lobius picivorus Germar
-V19
pitch-eating weevil
for
I-lylobius aliradicis Warner
-V19
southern pine root weevil
for
Members are requested to indicate any disapproval of any of these proposals within 30 days of receipt of this
issue of the BULLETIN. Reasons for disapproval must be given. Unless substantial objections are submitted the
proposals will be adopted by the Society.
C. C. Blickenstaff, Chairman
Committee on C011lmon Names of Insects
CHARLES
VALENTINE
RILEY
The September 1963 issue of the BULLETIN OF THE
ENTOMOLOGICALSOCIETY OF AMERICA contained
an
article on page 183 regarding First President C. V.
Riley, who was one of the 25 founders of the American
Association
of Economic Entomologists.
We noted
there the permanent loan to the Society of Riley woodcuts by the American Museum of Natural History. In
addition we acknowledged a gift from the Misses Thora
),1. and Cathryn V. Riley of a bronze statue presented
to their father by the French Grape Growers in 1892.
This statue continues to occupy a nitch of prominence
in the entry hall of the Entomological Society of America
building.
Recently the Misses Riley have presented to the
Society a gold medal about the size of a silver dollar.
On one side is the legend "International Forestry Exhibition, Edinburg 1884." On the other, "Awarded to Professor Riley, Washington, for Collection of Insects injurious to Forest Trees." Also "BE AYE STICKIN IN A
TREE, IT'LL BE GROWINWHEN YE'RE SLEEPIN." At the
same time they presented their father's medal of the
Legion of Honor (Chevalier, Legion D'Honneur).
This
is dated 1870. These mementoes of a founding father
are of interest and value to the Society and it is a pleasure to publicly thank the Misses Riley.
235