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A series of insecticidal dihydropyrazoles and related compounds have been shown to exhibit negative cross-resistance to a resistant (super-kdr) strain of houseflies with site-insensitivity to pyrethroids. The level of cross-resistance is similar to that observed previously for a range of N-alkylamides against the same strain.

A high performance liquid chromatographic reversed-phase procedure has been developed whereby azadirachtin content can be estimated in crude extracts of neem and in dust formulations of neem. An estimation of the azadirachtin content is achieved through the use of an external azadirachtin standard and valley-to-valley integration. Since azadirachtin seems to be the most potent insect feeding deterrent in these extracts and formulations, its content is a measurement of potency and represents an attempt at standardization.

Azadirachtin is a tetranortriterpenoid insect feeding deterrent and growth regulator present in the kernels of the neem tree, Azadirachta indica A. Juss. A procedure was developed whereby 8.7 g of >90% pure azadirachtin was obtained from 48.2 kg of neem kernels by the use of open-column reversed-phase liquid chromatography on Phase-bonded C-18 Hi-Flosil and high-performance liquid chromatography on μ Bondapak C-18 for monitoring (217 nm) the purification.

Twenty natural and synthetic substances, known or reported to be repellent to insects, were evaluated for repellency to adult house flies, Musca domestica L., by a new laboratory test method. Fourteen materials completely repelled the flies during a 30‐min test period. The most active material was 2‐phenylethanol.

A pheromone released by courting male tobacco budworm moths, Heliothis virescens (F.), to repel other males of that species has been identified as (Z)‐9‐tetradecenal. The amount of this compound isolated from 3‐day‐old male abdomens was 1 mg/male.

A joint research program was initiated in 1979 to investigate the potential avian repellency and toxicity of 55 selected insect repellents originating from or related to naturally occurring chemicals. Seven of the chemicals or extracts tested exhibited avian repellency and two of these were considered to be moderately active, with R50’s (analogous to LD50) of 0.237 (trans‐asarone) and 0.240% (safrole). None of the 55 chemicals or extracts exhibited acute oral toxicity at 100 mg/kg or less to the red‐winged blackbird (Agelaius phoeniceus).

Ethanolic extracts of fresh neem seeds were formulated as aqueous suspensions and defatted ground neem kernels were formulated as non‐wettable dusts for greenhouse studies with fall army‐worm larvae, Spodoptera frugiperda (J. E. Smith). First stage larvae of the fall armyworm were fed neem‐treated Golden Bantam sweet corn. The antifeeding potency of 0.2 and 0.4% aqueous solutions of the neem seed extract was maintained for at least 21 days. Tests with formulated dusts showed moderate activity against 1st stage fall armyworm larvae.

Pheromones, Olfactory Receptors, Structure-response Relationships, Lepidoptera Electroantennogram (EAG) data reflecting response spectra of male pheromone receptors have been analyzed for 16 species of Noctuidae (Lepidoptera). The test compounds included 100 phero­ mone analogues, altered in chain length, in position and configuration of double bond(s), and in the functional end groups. On comparison of amounts of substance required to elicit an equivalent EAG response, a single compound was determined to be most effective on a given species; these structures, either known or proposed as the natural sex pheromones of the species, were cis-1-dodecen-1-yl acetate, cis-7-tetradecen-1-yl acetate, cts-9-tetradecen-1-yl acetate, Jrarcs-9-tetradecen-1-yl acetate, cis-ll-hexadecen-l-yl acetate, cis-9, trans-12-tetradecadien-l-yl acetate, cis-9-tetradecen-1-yl formate, and cts-9-tetradecen-1-ol, respectively. Elongation (shortening) of the chain by 1 or 2 methylene groups, the movement of a double bond 1 carbon from the optimum, a change to the opposite geometrical isomer, or the introduction of a second double bond invariably reduced EAG responses to 1.8 to 56 times below that observed with the most stimulating compound, in all 16 species. Further alterations in chain length or in double bond position caused even greater reduc­ tion in activity, as did certain changes in end group (Tables I and II). A set of distinct rules could be derived from these structure-response relationships; one of these rules concerns the optimum position of the double bond(s) in relation to chain length, and another one the ratios in activity values produced by end group variations, irrespective of chain length. The same rules described here for 16 noctuid species held also for the structure-response relationships observed within various additional groups of Lepidoptera. From EAG values determined in this study, an attempt has been made to calculate physico­ chemical propteries of underlying acceptor structures.

Mise en evidence et caracterisation de lactones produites par le mâle du diptere Anastrepha ludens, agissant comme attractifs vis-a-vis de la femelle. Etude de l'activite possible de pheromones sexuelles par ces composes

The volatile components (ppm of total solids) emitted by corn silk were found to be l‐butanol (1), 1‐pentanol (7), 1‐hexanol (1), (E)‐4‐hexen‐1‐ol (4), 3‐methyl‐1‐butanol (1), acetaldehyde (5), hexanal (4), 2‐furancarboxaldehyde (furfural) (2), and phenylacetaldehyde (12). Phenylacetaldehyde was found to attract the corn earworm, European corn borer, soybean looper, tarnished plant bug, Cisseps fulvicollis, and forage looper. Combining phenylacetaldehyde with butanol or acetaldehyde increased attractiveness to some species; other combinations reduced attractiveness.

The fragrant chemical compound volatilized by the bladder flower, Araujia sericofera Brot., was identified as phenylacetaldehyde. It attracted many economically important species of moths, and when it was used with a blacklight trap, it increased trap collections of pest moth species by 48%.

Fifteen acids present in the natural sex pheromones produced by male Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were separated by gas‐liquid chromatography and identified. Then combinations of the acids and of previously identified pheromones were bioassayed for attraction to virgin female Mediterranean fruit flies in an outdoor olfactometer. However, when 2 of the most promising combinations were tested in the field, they attracted large numbers of males, but no females. In the laboratory, females reared from fruit infested in the field responded to the synthetic pheromone. No explanation is available for these anomalous results.

During the growing season in 1975 traps baited with (Z,E)‐9,11‐tetradecadien‐l‐ol acetate (9,11‐TDDA), the natural sex pheromone of Spodoptera (Prodenia) littoralis, were distributed in safety belts around 5,000 dunams of cotton, alfalfa, and stonefruit crops in the Upper Galilee and 1,500 dunams of cotton, alfalfa, and peanuts in the Beth‐She'an Valley of Israel. Other unprotected crops in the surrounding areas served as controls. A total of 219 traps at Neot Mordechai caught almost 300,000 male S. littoralis moths during the growing season (June‐September). PeaV captures at Neot Mordechai occurred in August, whereas optimum captures at Beth‐She'an occurred in September. Total seasonal average captures per trap were 1300 in the Upper Galilee and 350 in Beth‐She'an, the latter reflecting a much lower population density. In all experimental areas protected by the pheromone traps the number of insecticidal treatments necessary to control crop damage was much lower than the number of treatments requ...

Plants constitute a vast cornucopia of chemical substances used for defense from attack by insects. These may be classified as insect attractants, repellents, toxicants, inhibitors of growth and development, sterilants, and feeding deterrents. An overview of the subject and its interrelationships with man is presented.

Formulations of six samples of (Z,E)‐9,11‐tetradecadien‐l‐ol acetate (9,11‐TDDA), the sex pheromone of Spodoptera littoralis Boisd., synthesized at Beltsville and a sample synthesized in Japan by another method were compared for attractiveness in the fields of Israel. The Japanese sample was 20–50% more attractive than the others, despite the fact that it was contaminated with the (E,E)‐isomer, which was shown to delay optimum attraction in the Beltsville samples (but not in the Japanese sample) during the first 4–5 nights of exposure. Beltsville 9,11‐TDDA freed of the (E,E)‐isomer was still somewhat inferior to the Japanese pheromone in attractive power. A component present only in the Japanese sample and observable by capillary column gas chromatography was at first believed to be (Z,E)‐8,10‐tridecadien‐l‐ol acetate, but total synthesis of the compound showed this not to be the case; it was neither attractive per se nor synergistic with 9,11‐TDDA of Beltsville origin. (Z,E:)‐9,12‐Tetradecadien‐...

Candidate mating inhibitors for 3 lepidopterous cotton pests were screened out of 90 synthetic pheromone-like compounds, using the electroantennogram recording technique. ( E )- and ( Z )-9-tetradecen-1-ol formate, ( Z,E )-9,12-tetradecadien-1-ol formate and ( Z )-3-dodecen-1-ol formate, were most stimulatory to male Earias insulana Boisduval, ( Z )-9-tetradecen-1-ol formate and ( Z )-11-hexadecenal were most stimulatory to Heliothis armigera (Hubner) and ( Z )-9-tetradecen-1-ol acetate was, next to the natural pheromone ( Z,E )-9,11-tetradecadien-1-ol acetate, most stimulatory to Spodoptera littoralis Boisduval. In field tests ( Z )-9-tetradecen-1-ol formate and ( Z )-9-tetradecen-1-ol acetate, released from virgin female baited traps, were equally effective in inhibiting male capture in all 3 species.

In both laboratory and field tests over a 3-yr period, solvent extracts from seeds of the neem tree, Azadirachta indica A. Juss., successfully deterred Popillia japonica Newman from feeding on sassafras leaves, Sassafras albidum (Nutt.), and soybeans, Glycine max (L.). In most instances, untreated foliage was completely destroyed, whereas leaves protected with the neem extracts remained untouched or, at worst, were only slightly damaged.

Aqueous solutions of neem seed extract applied on leaves were evaluated for antiovipositional and insecticidal effects against the leafminers Liriomyza sativae Blanchard and L. trifolii (Burgess). All experiments but one were conducted with the primary leaves of Henderson bush lima bean as the host. Significantly fewer eggs were laid by L. trifolii females in neem-treated foliage than in water-treated foliage; such a difference in oviposition was not seen for L. sativae . However, larval mortality of both species shortly after hatch was high (100% for L. trifolii . 98.2% for L. sativae ). Further work indicated that 2-to 6-h-old neem residues on leaves repelled adult L. sativae . thus reducing oviposition, but that 22-h-old residues were not appreciably repellent. Neem applied as a 0.1 % solution on leaves was active against 1- to 3-day-old L. sativae eggs (by killing larvae hatching from those eggs) as well as against all three larval instars. Against L. sativae eggs and larvae, neem was highly effective as 0.1 and 0.05% solutions (91 to 100% mortality) and moderately effective as a 0.025% solution (49 to 92% mortality). Neem applied on leaves was effective for up to 7 days in killing larvae hatching from eggs, but its effectiveness declined steadily from day 0 after application (86% mortality) to day 7 after application (44% mortality). Adults caged for 25 h with foliage freshly dipped in 0.1% neem extract showed no adverse effects. Similarly, neem extract (0.1%) applied on chrysanthemum leaves showed that adult L. trifolii were slightly inhibited from making ovipositor punctures in leaves. Leaf-miners failed to develop, however, and the neem-treated leaves contrasted with the control leaves, which contained numerous mines.

The continuous use of gossyplure‐baited traps in 1974–1975 for monitoring infestations of the pink bollworn moth in cotton fields succeeded in reducing the percentage of infested bolls to less than 5% in the Hagilboa and Beth‐She an regions of Israel. The average number of insecticidal treatments necessary to control the pest was likewise reduced from 5.8 in 1974 to 1.64 in 1975 in Beth‐She’ an and from 2.9 to 2.21 in Hagilboa. The monitoring threshold of 8 males captured per trap per night to determine the need for pesticide treatment, instituted in 1975, proved, as expected, to be a less accurate yardstick than the threshold of 5 males per trap per night previously recommended. Crude or distilled cottonseed oil was more efficient for use in the trap cups than the aqueous detergent solution used heretofore, and the traps themselves were considerably improved by providing a plastic rooflet above the cups.

A sex pheromone, detected in female moths of the bertha armyworm, Mamestra configurata Wlk., was extracted from females that were more than 3 days old. Males responded to the pheromone from 2 days of age until they died; younger males were not tested. Chemical and bioassay analyses indicated that the pheromone was an acetate.The stimulatory effect of several chemicals was determined with males in a laboratory bioassay. Sexual responses were induced by Z7-, Z9-, Z10-, Z11-, and Z13-hexadecen-1-ol acetates. The maximum response in the laboratory was from the Z10-isomer, but this compound was only weakly attractive to males in the field.

The southwestern pine tip moth, Rhyacionia neomexicana (Dyar), is a destructive pest of young ponderosa pine trees. Male moths are attracted to traps containing virgin females, but chromatographic fractions of female abdominal tips failed to entice males. A variety of synthetic materials were field tested at Chevelon, Arizona over a 6‐year period (1971–1976). (Z)‐7‐Dodecen‐l‐ol acetate, (E)‐7‐dodecen‐1‐ol acetate, and especially (E)‐9‐dodecen‐1‐ol acetate were attractive to the male moth. However, none of the synthetic compounds was as effective as live virgin females.

By using only females individually attractive to males during that time of night when most matings occur, the writers were able in one season to recover the substance that attracts the male to the female tobacco hornworm ( Protoparce sexta (Johannson)) and to demonstrate that the attractive substance was present in the experimental material as well as in a chemical extract of that material. The procedure used to recover the sex attractant is described.

Isolation and characterization of the naturally occurring sex attractants of the silkworm moth (Bombyx mori), gypsy moth (Porthetria dispar), cotton leafworm (Prodenia litura), American cockroach (Periplaneta americana), an introduced pine sawfly (Diprion similis), and mating attractants of the honey bee (Apis mellifera) and bumblebee (Bombus terrestris) are discussed.

In trapping tests conducted in Israel cotton fields, propylure failed to show attractancy to male pink bollworm moths when used alone or in combination with deet, hexalure, antioxidant, or dodecyl acetate. A formulation of hexalure (and antioxidant) containing acetone was at least four times as attractive as one containing four times as much hexalure (and antioxidant) without acetone. Dodecyl acetate inhibited the response to hexalure, whereas linalyl acetate enhanced the response considerably.

Adsorption and gas-chromatograhic methods are described for determining the content of cis -gyplure in samples of gyplure prepared in the laboratory and the pilot plant, as well as for separating the cis isomer from its contaminats.

Electrophysiological responses were determined on the antennae of the 3 castes of Apis mellifera L. to trans -9-oxo-2-decenoic acid (“queen substance”) and its cis isomer. In addition, electroantennograms (EAG’s) were obtained with 3 structural analogues of queen substance on the drones. The EGA’s correlated with the results of stronger responses than the cis isomer or the other test compounds. Marked differences were noted between the response of drone, worker, and queen honey bee antennae to the trans isomer.

Forty-six compounds (17 alcohols and 29 acetates) were tested electrophysiologically (electroantennograms) at 100 µg/cartridge on 4 species of lepidopterous insects (male and female Diatraea grandiosella , Dyar, male and female Manduca sexta , (L.), male Heliothis virescens (F.), and male Platynota stullana Walsingham). Those compounds eliciting the greatest response were tested at lower concentrations until a response was no longer obtained. Responses were compared with those elicited by a methylene chloride extract of abdomens of virgin females of the same species. Compounds eliciting the greatest responses for males at the lowest concentration were the acetates of 7-octen-1-ol, 8-nonen-1-ol, trans-5 -decen-1-ol, cis- 6-doclecen-1-ol, trans -6-dodecen-1ol, dodecen-1-ol, cis-8-dodecen-1-ol, and ris-9-dodecen- 1-ol. and tralls-2-hexen-1-ol. Of these compounds, 8-nonen- 1-ol acetate elicited a response from male M. sexta at a dose of 10-0 µg.

Pure sex pheromone was isolated from virgin female Carpocapsa pomonella (L.) by a procedure consisting of extraction of whole female moths, refluxing in methanolic sodium hydroxide to release chemically bound attractant, solid-liquid chromatography on alumina, preparative scale gas chromatography on carbowax-20M, and finally gas chromatography on apiezon L. One-day-old females each contained 0.03 ng of free and 0.22 ng of bound pheromone, whereas 3-day-old females each contained 0.30 ng of free pheromone and 0.25 ng of bound pheromone. This is less pheromone per insect than has been previously reported for any other species. Chemical and chromatographic data indicate that the pheromone is an unsaturated alcohol, does not contain a carbonyl group, but docs contain at least 1 other functional group. Gas chromatography at 200°C showed that the Kovats' retention index, I, was 2235 on the carhowax-20M column and 1515 on the apiezon L column.