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A 3-layer laminated plastic dispenser of disparlure, the sex pheromone of the gypsy moth, Porthetria dispar (L.), was effective in laboratory and field trials for an entire season and emitted lure at a fairly uniform rate whether its ends were open or sealed. Because lure content of the dispensers dropped very little after a season of exposure, the rate of emission of the laminates should be increased to increase attraction and make more efficient use of the lure. Cotton wicks performed as well as the laminated dispensers in the field, but in the laboratory their emission rates dropped sharply initially and then continued at a rate ca. 10-fold less than that of the laminates. Triangular traps caught more males than Johnson traps when both were baited with the same dispenser.

A new type of bait dispenser for insect traps is a 3-layer plastic laminate in which pheromone is concentrated in the inner layer. When the dispenser was compared with currently used dispensers of pheromone of the cabbage looper, Trichoplusia ni (Hubner), and of the gypsy moth, Porthetria dispar (L.), the laminate dispenser generally caught greater numbers of insects. Also, in an aging test, the attraction of the laminate dispenser containing gypsy moth pheromone remained high for 120 days, and even the aged laminates outdrew freshly baited, standard bait-dispensers in all but one instance. Dispensers that emit lure at a constant rate are needed if traps are to be used for reliable estimates of insect populations.

Analysis of heptane-soluble compounds from ovipositors of Heliothis zea and Heliothis virescens shows that both species produce relatively large amounts of (Z)-11-hexadecenal, with traces of (Z)-9-hexadecenal, (Z)-7-hexadecenal, and hexadecanal. Heliothis virescens females differ from Heliothis zea in that they also produce trace amounts of tetradecanal, (Z)-9-tetradecenal, and (Z)-11-hexadecen-1-ol. In both species, trace compounds are essential to pheromonal activity and specificity of chemical signals.

In simulated field tests in advance of the natural flight of Porthetria dispar (L.), laboratory-reared males were released, and the number attracted to traps containing live virgin females was compared with the number attracted to traps baited with formulations of disparlure, cis -7,8-epoxy-2-methyloctadecane, the newly synthesized sex lure of the gypsy moth. The lure was formulated with trioctanoin to regulate its volatility. Pure disparlure and many of its formulations attracted more males than did the live female. The attraction of the female was estimated to be equivalent to 1-6 μg of disparlure in 5 mg of trioctanoin. Information on the attraction of the synthetic lure relative to that of the females provides a basis for estimating the role of traps containing disparlure in the suppression of low-level or incipient populations of the gypsy moth.

Tetradecyl acetate and several related compounds when combined with hexalure ( cis -7-hexadecen-l-ol acetate) suppress the attraction of pink bollworm, Peclinophora gossypiella (Saunders), moths to hexalure. If these chemicals inhibit the detection of the natural female sex attractant, they may be useful in preventing male moths from locating females for mating.

The 2 tortricoid moths attacking grapes in Europe, Eupoecilia (Clysia) ambiguella (Hb.) and Lobesia (Polychrosis) botrana Schiff. were among the first agricultural pests studied in sex pheromone research. Investigations by Gotz (1941a,b; for a complete bibliography see Jacobson, 1972) already concerned laboratory bioassay of the pheromone, use of clock traps to determine diurnal rhythms, and mass-trapping for control. The work was done explicitly with today’s objective: to do away with toxic chemicals. It is interesting to speculate whether the 30-year interruption in this line of work had more to do with wartime or simply with the advent of more effective insecticides.

Muscalur, der Lockstoff der weiblichen Hausfliegen, wurde durch Dunnschicht und Gaschromatographie rein isoliert und nach Ozonolyse zu Nonal (I) und Tetradecanal (II), sowie nach Hydrierung zu n-Tricosan (IV) und Vergleich mit cis- und trans-9-Octadecen als cis-9-Tricosen (III) identifiziert.

13-Methylhentriacontane has been identified in the feces and larvae of the corn earworm, Heliothis zea (Boddie), as the major constituent that triggers the short-range host-seeking response of the parasite Microplitis croceipes (Cresson). This chemical, the first found that mediates the complex host-parasite relation, could upgrade present efforts to use parasites for insect control. Bioassay of closely related compounds indicated that the structural requirements for activity are remarkably specific.

3,5-Bis-amino-1,2,4-dithiazoliumbromide (Ia)-(Ic) reagieren mit Kaliumcyanat uber diskutierte Zwischenstufen (II) und (III) zu den Thiadiazinonen (IVa)-(IVc).

The sex attractant emitted by the female gypsy moth has been identified as cis-7,8-epoxy-2-methyloctadecane. The structure was verified by spectral, gas chromatographic, and biological comparisons with the synthesized compound. Nine closely related isomers were considerably less effective.

A small ozone generator useful for locating double bonds inμg amounts of organic compounds is easily constructed from an inexpensive vacuum tester. The unit is also useful for micro-preparative purposes.

A sex pheromone isolated from the cuticle and feces of the female house fly attracts the male fly; it has been identified as (Z)-9-tricosene. Chemical and biological comparisons of the natural and synthesized compounds show that they are identical.

Gypsy moth kairomones influencing host recognition responses of two species of hymenopteran parasitoids, the chalcicid Brachymeria intermedia (Nees) and the braconid Apanteles melanoscelus (Ratz.) were recovered from the gypsy moth, Porthetria dispar L. A kairomone for B. intermedia was removed by washing gypsy moth pupae with hexane. The pupal wash, when exposed on filter paper to B. intermedia females, elicited an antennal response characteristic of adults when they find host pupae. A kairomone for A. melanoscelus was obtained by washing gypsy moth larvae with hexane. For A. melanoscelus , antennal responses were recorded with hexane washes of gypsy moth larvae, but not of pupae, and for B. intermedia , responses occurred with hexane washes of pupae, but not of larvae. Work on identification of the kairomones is in progress.

( Z )-ll-hexadecenal was isolated and identified from virgin female Heliothis zea (Boddie) via classical chemical procedures. The chemical elicits strong sex stimulation reactions among caged laboratory males. However, the chemical does not catch males in sticky or electric grid traps in the field. In fact, minute quantities inhibit the male catch of 4 virgin females/trap in sticky traps located in the field.

Although (E,E)-8,10-Dodecadien-l-ol was reported to be a sex pheromone of the codling moth [Laspeyresia pomonella (L.)], its presence in the moth was questioned, mainly because it has not been isolated. A computerized search of data from gas chromatography-mass spectrometry of a partially purified extract equivalent to 45 abdominal tips of female moths produced a mass spectrum that matched that of the authentic coinpound. Other data also confirmed the presence of the compound.

E or Z allylic Grignard reagents reacted with allylic halides in tetrahydrofuran-Hempa to give products in which the double bond from the organometallic fragment was predominantly Z. Protonation of the allylic Grignard reagents gave an increased proportion of Δ2-alkene and a higher ratio of Z:E isomers when Hempa was added.

A phthalate ester, recently isolated from thermally oxidized corn oil, has been identified as di-2-ethelhexyl phthalate.

Disparlure ( cis -7,8-epoxy-2-methyloctadecane), the sex pheromone of the gypsy moth, Porthetria dispar (L.) (Bieri et al. 1970), and 55 related compounds (Sarmiento et al. 1972) were tested in Japan as attractants for the so-called Japanese gypsy moth, P. d. japonica (Motschulsky). The Japanese gypsy moth closely resembles the North American species, but it is much larger (as much as 50%). Authorities at the United States National Museum of Natural History consider the Japanese gypsy moth a distinct Subspecies of P. dispar .