Experimental Insecticides Research Articles

Experimental Insecticides Applied as Sprays to Control Thrips and the Cotton Fleahopper1234

In field experiments Bidrin® (3-hydroxy- N , N dimethyl- cis -crotonamide dimethyl phosphate), Shell SD-9129 (dimethyl phosphate ester with 3-hydroxy- N -methyl- cis -crotonamide), and Mobil MCA-600 (benzo[ b ] thien-4-yl methylcarbamate) compared favorably in control of thrips ( Frankliniella sp.) with carbaryl. and American Cyanamid CL-47470 [cyclic propylene (diethoxyphosphinyl) dithioimidocarbonatc], CL-47031 [cyclic ethylene (diethoxyphosphinyl) dithioimidocarbonate[, and phosphamidon were as effective as toxaphene + DDT. Bidrin, Geigy GS-13005 [ O , O -dimethyl phosphorodithioate S-cster with 4-(mer-captomethyl)-2-methoxy-△2-1,3,4-thiadiazolin-5-onc]. MCA-600. and SD-9129 gave control of the cotlon fleahopper. Psallus seriatus (Reuter), equal to that obtained with toxaphene + DDT. A comparison of visual plant terminal inspcction and a vacuum machine for sampling the cotton fleahopper population indicatcd that the visual method was the most efficicnt for sampling nymphs.

Two Promising Experimental Insecticides for Control of the Plum Curculio1

Field trials of Bayer 37344 (4- (methylthio) –3,5-xylyl methylcarbamate) and Imidan® (phthalimidomethyl O,O -dimethyl phosphorodithioate) were made in 1961 through 1964 for control of the plum curculio, Conotrachelus nenuphar (Herbst), on 4 varieties of plums. The materials were applied in a series of 3–5 sprays from bloom ot petal fall through the second or third cover spray. Both experimental insecticides gave excellent control of the plum curculio. A laboratory test against the summer adults indicated that Bayer 37344 and Imidan were comparable in effectiveness to our presently recommended insecticides. No problems in phytotoxicity were evident.

Residues in hen eggs from vaporizing insecticide tablets.

Experimental insecticide tablets containing lindane, paradichlorobenzene, and dichlorvos, designed to control chicken ectoparasites by vapor action, were attached to the wire floor of individual battery cages. Eggs were collected at intervals and assayed for lindane by a colorimetric method and by electron capture gas chromatography. Lindane was found in the yolks by both methods, reaching a maximum after 20 days' exposure. Maximum residues detected were 0.13, 0.24, and 0.33 ppm lindane for 2, 4, and 8 tablets.

Control of the Alfalfa Weevil, Hypera postica, in New York

Experiments were conducted to determine the effectiveness of experimental, labeled, and mixtures of various insecticides for controlling the alfalfa weevil, Hypera postica (Gyllenhal), on fall, first-, and second-crop alfalfa. Fall-applied methoxychlor and a mixture of Guthion M-E® (O,O-diethyl S-(4-oxo-1,2,3-benzotriazin-3(4H)-yl-methyl) phosphorodithioate) and 3% Igepal CO-630® (nonylphenoxypoly(ethyleneoxy)ethanol 9–10 ethyleneoxy per mole of nonylphenol) did not give adequate control and both were below the normal performance of the standard fall-applied heptachlor. None of the stubble sprays, except HRS 1671 (heptachlorohexahydroketomethanophthalan), gave better control than lindane and few were more effective than the already recommended materials that were tested. Of the experimental insecticides tested, HRS 1671, Bayer 41831 (O,O-dimethyl O-(4-nitro-m-tolyl)phosphorothioate), AC 47031 (2-(diethoxyphosphinylimino)-1,3-dithiolane), AC47772 (2-(dimethoxyphosphinylimino)- 4-methyl-1,3-dithiolane), and R.P. 11974 (0,0-diethyl dithiophosphoryl methyl-3-chloro-6-benzoxazolone) showed the most promise.

Evaluation of Systemic Insecticides for Cotton Insect Control1

Four experimental systemic insecticides, American Cyanamid compounds CL-47031, CL-47470, CL-43064, and E. I. 47772, were compared in one or more tests with phorate, Di-Syston®, Bidrin®, phosphamidon, demeton, methyl parathion, and Guthion®-Ethyl Guthion® for cotton insect control. When applied in or near the seed furrow, as sidedressings to established plants, directly to the stem, or as foliar sprays, one or more of the experimental compounds was equal or superior to currently available compounds. The insects and mite used for biological evaluation included the boll weevil, Anthonomus grandis Boheman; cotton aphid, Aphis gossypii Glover; carmine spider mite, Tetranychus cinnabarinus (Boisduval) ; cotton leafworm, Alabama argillacea (Hubner); and salt-marsh caterpillar, Estigmene acrea (Drury). In considering results from all methods of application, CL-47031 and CL-47470 appeared to be the most promising of the experimental compounds tested. The chemical names of those compounds without approved common names included in these studies are: CL-47031, cyclic ethylene (diethoxyphosphinyl) dithioimidocarbonate; CL-47470, cyclic propylene (diethoxyphosphinyl) dithioimidocarbonate; CL-43064, cyclic ethlene (diethoxyphosphinothioyl) dithioimidocarbonate; E. I. 47772, cyclic propylene (dimethoxyphosphinyl) dithioimidocarbonate; Di-Syston®, O,O -dicthyl S-[2- (ethylthio) ethyl] phosphorodithioate; Bidrin®, 3-hydroxy- N,N -dimethyl- cis -croton-amide dimethyl phosphate; and Guthion® plus Ethyl Guthion®, O,O -dimethyl S -(4-oxo-1,2,3- benzotriazin-3 (4 H ) -ylmethyl) phosphorodithioate.

Control of Certain Cotton Pests with a New Systemic Insecticide, UC-211491

An experimental systemic insecticide, Union Carbide UC-21149 (2-methyl-2- (methylthio) propionaldehyde O- (mcthylcarbamoyl) oxime), was compared with Di-Syston® ( 0,0 -dicthyl 5-[2- (ethylthio) ethyl] phosphorodithioate), and phorate in granular formulations applied at planting as in-furrow treatments for control of early-season cotton insects. Additional tests were conducted with UC-21149 as seed treatment or sidedress applied at various stages of cotton plant growth for control of the boll weevil, Anthonomus grandis Boheman. In the in-furrow treatments at planting, Di-Syston and phoratc adversely affected stands of cotton; but UC-21149 did not. UC-21149 was as effective as Di-Syston and phorate against a thrips complex [flower thrips, Frankliniella tritici (Fitch) ; F. exiguia Hood; tobacco thrips, F. fusca (Hinds); and grain thrips, Limothrips cerelium (Haliday)]; the cotton aphid, Aphis gossypii Glover; and an artificially induced infestation of the carmine spider mite, Tetranychus cinnabarinus (Boisduval). Mortality of overwintered boll weevils was significantly greater with UC-21149 and phorate than with Di-Syston. UC-21149 applied as a seed treatment reduced stands and was ineffective against the cotton aphid. Sidedress treatments produced significant mortality of boll weevil larvae developing within the squares and bolls, and of adults feeding on terminal growth. It also controlled the cotton aphid and carmine spider mite. However, UC-21149 was ineffective against the bollworm, Heliothis zea (Boddie), and cabbage looper, Trichoplusia ni (Hubner). Bollworms increased in 1 test, apparently owing to a lack of beneficial insects. Phytotoxicity was observed at the high rates shortly after treatment, but it did not appear to persist on subsequent plant growth.

Control of the Southwestern Corn Borer with an Experimental Systemic Insecticide

Control of the Southwestern Corn Borer with an Experimental Systemic Insecticide

Laboratory and Greenhouse Experiments With a New Series of Systemic Insecticides1

Five American Cyanamid Company experimental organophosphorus systemic insecticides, compounds 43064, 43356, 47031, 47071, and 47470, have been evaluated in the laboratory and greenhouse to determine their usefulness for systemic control of cotton-insect pests. Topical treatments of adult boll weevils, Anthonomus grandis Boheman, with the 5 experimental insecticides indicated that they were more toxic than phorate, but resulted in unusually flat dosage-mortality curves. Seed treatments of cotton with compounds 43064, 43356, and 47071 gave excellent control of adult boll weevils in greenhouse experiments for 10 to 11 weeks. Treatments with the phorate standard controlled weevils for only 6 weeks. Field experiments, however, indicated that compound 43064 was no more effective than phorate for control of aphids, thrips, or boll weevils, Chemical names of American Cyanamid Company compounds tested are: 43064, cyclic ethylene (diethoxyphosphinothioyl) dithioimidocarbonate; 43356, cyclic ethylene (dimethoxyphosphinothioyl) dithioimidocarbonate; 47031, cyclic ethylene (diethoxyphosphinyl) dithioimidocarbonate; 47071, cyclic propylene (diethoxyphosphinothioyl) dithioimidocarbonate; 47470, cyclic propylene (diethoxyphosphinyl) dithioimidoearbonate.

The Effects of Acaricides on the Developmental Stages of the Two-Spotted Spider Mite, Tetranychu telarius1

A battery of tests employing Tetranychus telarius (L.) as the test animal, Phaseolus vulgaris L. as the host plant, and a spray technique were designed to assess the immediate and residual adulticidal, nymphicidal and ovicidal effectiveness of acaricidal chemicals. Twenty commercial formulations and eighteen other organic molecules were tested. Kelthane® was the most generally effective. Chlorobenzilate®, Karathane®, Trithion® and ethion were to a greater or lesser degree effective against all stages of the mite. Tedion®, ovex and chlorbenside were effective against the immature and egg stages only. Aramite®, Dimite®, Dibrom® and malathion killed the motile stages but had little ovicidal effect. Thiodan® was among the least effective materials. The systemics, Ekatin-®, dimethoate, demeton, phosphamidon, Experimental Insecticide 18706, and Di-Syston® were primarily adulticides. Of the other organics tested only p-chlorobenzyl 2-chloroethyl sulfide and bis (p-chlorophenyl mercapto) propane gave any appreciable kill.

Commercial and Experimental Organic Insecticides

Commercial and Experimental Organic Insecticides

Commercial and Experimental Organic Insecticides

Commercial and Experimental Organic Insecticides

Commercial and Experimental Organic Insecticides

Entomologists and others concerned with insecticides and their uses are constantly confronted with the problem of keeping abreast of current and past developments on the subject of the chemical control of insects, other arthropods and similar pest animals. It is as important to identify the “species” of insecticides as it is the species of insect when attempting to control an insect pest.

Commercial and Experimental Organic Insecticides

Entomologists and others concerned with insecticides and their uses are constantly confronted with the problem of keeping abreast of current and past developments on the subject of the chemical control of insects, other arthropods and similar pest animals. It is as important to identify the “species” of insecticides as it is the species of insect when attempting to control an insect pest.

Commercial and Experimental Organic Insecticides

Commercial and Experimental Organic Insecticides

Field Evaluation of Sevin as an Insecticide for Pests of Vegetables in New Jersey12

Beginning in 1954 and in each subsequent year, 1-naphtllyl N -methylearbamate, identified either as Experimental Insecticide 7744 or Sevin®, has been tested in the field in New Jersey on a wide range of insects and vegetable crops. Using wettable powder (wp) formulations lit rates of 0.25 to lb., active ingredients per 100 gallons, it was found that Sevin could provide control of the cabbage flea beetle ( Phyllotreta cruciferae (Goeze)), potato leafhopper ( Empoasca fabae (Harr.)), European corn borer ( Pyrausta nubilalis (Hbn.)), corn earworm ( Heliothis zea (Boddie)) fall armyworm ( Laphygma frugiperda (J. E. Smith)), and the Mexican bean beetle ( Epilachna varivestis Muls.). Sevin was usually somewhat less effective at these rates against the squash bug (Anosa tristis (DeG.)) or cabbage leaf feeders such as the imported cabbageworm ( Pieris rapae (L.)), cabbage looper ( Trichoplusia ni (Hbn.)), or diamondback moth ( Plutella maculipennis (Curt.)) larvae. It was only moderately effective against the potato aphid ( Macrosiphum solaifolii (Ashm.)) and it appeared to favor buildup of the turnip aphid ( Rho palosiphum pseudobrassicae (Davis)), presumably by destroying some parasites and predators. Sevin did not control the two-spotted mite ( Tetranychus bimaculatus Harvey) on beans. Foliage injury was not apparent except after repeated spraying of corn (Iochief) in 1956 and 1957. This injury was not noticed in 1958. In general, Sevin did not appear to cause any marked effect on yield. This result was also true in respect to flavor or taste acceptability as judged by tests on crop samples taken from treated plots of lima beans, turnips, potatoes, and tomatoes. Residue analyses made on samples of crops taken on the clay sprayed indicated varying amounts of active chemical depending on the crop. Broccoli retained highest amounts, but available data showed that on this and other crops Sevin residue decreased to a relatively low level within a week.

Control of Peach Twig Borer on Almonds and Peaches in California

Numerous recently introduced and staple insecticides were tested for effectiveness against the peach twig borer, Anarsia lineatella Zell. Initial or preliminary evaluations were obtained by spraying small, nonbearing peach or almond trees and counting soon thereafter the twig terminals damaged by surviving larvae. The experimental insecticides which gave promising results in more than one of these twig-strike tests were further tested on mature peach trees for appraisal based on reduction of crop damage. Data obtained from all these tests indicate that, within the range of periods and dosages tried, Sevin® (1-naphthyl- N -methyl carbamate) and Thiodan® (6,7,8,9,10,10- hexachloro-1,5,5a ,6,9,9a-hexahydro -6,9 - mcthano-2,4,3- benzodioxathicpin- 3-oxide) have good potentialities for use against this pest of stone fruits. Sevin 50 WP and Thiodan 25 WP tended to yield consistently lower twig borer counts in twigs and fruits than DDT 50 WP--each used at 2 pounds of formulated material per 100 gallons-but the differences observed were not significant in every trial. Other insecticides which yielded low-strike counts in one or more of the trials on nonbearing trees were Guthion®( O,O -dimethyl S -(4-oxo-3H- 1,2,3-benzotriazine-3-methyl) phosphorodithioate), Diazinon® ( O,O -diethyl O -(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate), dieldrin, endrin, and malathion. Two applications of each of six insecticides tested on mature peach trees, one application in the pink bud or petal fall period and a second application for the May generation of larvae, reduced crop infestation to reasonably low levels but not within the range of safe or assured commercial control under conditions of severe infestation.

Investigations with New Insecticides for Codling Moth Control

Orchard trials with new insecticides for control of codling moth (Carpocapsa pomonella (L.)) on pears were conducted in two orchards in northern California during 1956. Diazinon alone, a combination of Diazinon and DDT, Thimet, Dipterex and a spore preparation of Bacillus thuringiensis Berliner failed to give satisfactory control. Trithion gave variable results, showing promise in one trial, but providing poor control in another. Hercules AC-528 showed some promise, and ryania, Sevin (N-methyl-l-naphthyl carbamate) and Guthion gave codling moth control comparable to the standard dosage of DDT. During 1957, orchard trials were continued on pears, and Sevin and Guthion gave good codling moth control. Guthion also controlled the European red mite (Panonychus ulmi (Koch)), and both Guthion and Sevin reduced a lepidopterous leaf miner infestation to a low level. Ryania, at a low dosage, plus a spreader-sticker, failed to provide adequate reduction of fruit injury by the cooling moth. In a New town Pippin apple orchard, a heavy codling moth infestation was found following grower application of a full DDT program. Field trials during 1957 in this orchard with DDT strongly indicated a resistance to this compound. In the same orchard, Trithion, ryania, Sevin and ethion provided satisfactory control of a heavy infestation. Trithion and ethion also provided control of European red mite, and Sevin prevented a build-up of the apple aphid Aphis pomi DeG. No serious phytotoxic effects were noted on pears or apples following the use of the experimental insecticides.

Studies on Corn Earworm Control in the Everglades

The corn earworm, Heliothis zea (Boddie), is the most damaging insect that attacks sweet corn in Florida. This is especially true as most of the corn is sold as fresh corn under the grade of U. S. Fancy. Among other requirements, a U. S. Fancy ear must show no evidence whatever of corn earworm attack to the ear itself or even within the silk channel. No vegetable pest requires a more intensive spray program than that necessary to control this pest. Everglades growers spray or dust at least every other day from the time the first silks appear within a planting, until all the silks are dry. Where large acreages of corn are involved, the same sprayer or duster may be operated 24 hours a day. The author's primary objective in corn earworm control studies on sweet corn is to find ways to reduce the number of necessary insecticide applications, and, at the same time, maintain a high degree of corn earworm control. To date the fulfillment of this objective has not been accomplished. Spray applications were made with a high-clearance, self-propelled sprayer built at the Everglades Experiment Station 2. A Myers jumbo nozzle fitted with a No. 3 disc was used on each side of the sweet corn row. The nozzles were at approximately the same height as the silks, and at a right angle to the stalks. The spraying pressure was 200 pounds per square inch. For all trials, Golden Security variety of sweet corn was planted in rows that were three feet apart and thinned to give a 12-inch spacing within the row. Budworm and disease control was accomplished with DDTparzate sprays until the time of silking. Experimental insecticide applications were begun the day after the first silks appeared and continued until all silks were dry. In each experiment a randomized complete block design employing four replications was used. A 100-ear sample was examined in each plot to determine the percentage of ears that were free of earworm injury. Before analysis of variance was conducted, these percentages were transformed to angles (arc sin V % ).