Release kinetics of liquid flowable formulations of gossyplure, sex pheromone of the pink bollworm mothPectinophora gossypiella saunders (Lepidoptera: Gelechiidae).

The kinetics of the release of gossyplure, measured in the laboratory at 34.5 ± 0.5 °C, from two liquid flowable formulations are presented and discussed. The data indicate that liquid flowable formulations, defined as those formulations where the active ingredient (in this case gossyplure) is attached to a particulate material, which in turn is suspended in a liquid medium, probably can be successfully used to disseminate pheromones and other behavior-modifying chemicals, although much work remains to be done in the development of these and other liquid flowable formulations.

Ultrastructure of exocrine prothoracic gland ofDatana ministra (Drury) (Lepidoptera: Notodontidae) and the nature of its secretion.

Datana ministra larvae possess a gland situated in the ventral anterior portion of the prothorax. The gland consists of a single sac and is only charged with secretion in the last instar. Its orifice, a simple slit, opens into a transverse invagination of the integument in the cervical margin of the prosternite. The components of the gland have been identified by GC and GCMS and have been shown to be dodecanol, dodecyl acetate, and dodecyl formate. The morphology of the gland and the chemistry of the secretion are discussed in relation to other notodontid larvae which have been investigated. It is conjectured that the secretion is not defensive in nature but may function as a dispersal pheromone.

Determining pheromone content of hairpencils from individual virgin males ofPseudaletia unipuncta (Haw.) (Lepidoptera: Noctuidae).

Levels of benzaldehyde recovered from virginPseudaletia unipuncta (Haw.) males were not influenced by (1) the time hairpencils remained in the solvent (1-72 hr), (2) anesthetization or agitation of males prior to excision of hairpencils, or (3) the time (photophase or scotophase) that hairpencils were excised. Thus the interindividual variability observed is not a methodological artifact. Most males had similar concentrations in both hairpencils, although in some cases only one hairpencil contained pheromone. In one case, a male with partially extruded hairpencils had no benzaldehyde at all. Neither pupal weight nor hairpencil length proved to be reliable indicators of pheromone content.

Capillaries as controlled release devices for insect pheromones and other volatile substances-A reevaluation : Part I. Kinetics and development of predictive model for glass capillaries.

Controlled release formulations are required for the dissemination of behavior-modifying chemicals in insect control strategies. Among the types of formulations that have been used for some time are glass and plastic capillaries. Erratic release rates on field use of such capillaries prompted us to reexamine the release of volatile materials with regard to (1) kinetics of the release, (2) the effect of the vapor-air column above the liquid, and (3) developing a predictive model. Results indicate that the release is not zero order, and that the length of the vapor-air column is a critical factor of the system; a predictive model has been developed that will allow better design of capillary controlled-release formulations.

Capillaries as controlled release devices for insect pheromones and other volatile substances-A reevaluation : Part II. Predicting release rates from Celcon and Teflon capillaries.

A predictive model developed for the release rates of volatile materials from glass capillaries was invalid when tested with Celcon fibers used commercially in pheromone-based insect control strategies. Several factors which might explain the differences between the predicted and observed rates are discussed, and it is hypothesized that the topography of the fiber lumen is the major factor causing the observed rates to deviate from the predicted values and the large variation in rate from fiber to fiber. This hypothesis was tested using Teflon capillary fibers with both smooth and rough lumen walls and shown to be valid. This indicates that commercial hollow-fiber pheromone formulations can be improved both in efficiency and cost by careful selection of fiber material, improvement in fiber manufacturing, and the use of a predictive model in formulation design.

Commercial hollow-fiber pheromone formulations: The degrading effect of sunlight on celcon fibers causing increased release rates of the active ingredient.

The effect of weathering on the release of pheromone analogs from Celcon fibers has been studied. Results from fibers exposed in Quebec indicate that UV radiation in sunlight degrades the Celcon, causing an increase in the release of the active materials. The results are discussed in the light of large interfiber release rate variation experienced with commercial fiber formulations, and the fact that the major use areas, to date, have been Arizona and California where the effect is likely to be much more pronounced. Stability of the release device to weathering is shown to be one of the many parameters to be considered in formulation design.

[Adsorption on "Porapak Q" of the effluvia emitted by virgin females of Choristoneura fumiferana (Clem.) (Lepidoptera, Tortricidae). Identification of tetradecene-11(E)al-1, principal sex pheromone of this species]. / Adsorption sur "Porapak Q" des effluves émis par la femelle vierge de Choristoneura fumiferana (Clem.) (Lépidoptère Tortricidae). Mise en évidence du tétradécène-11(E)al-1, principale phéromone sexuelle de cette espèce

Air which had been drawn over virgin female Choristoneura fumiferana was passed through "Porapak Q", in this way an extract containing all the volatile compounds emitted by the insect may be obtained. (E)-11-tetradecenal but not (E)-11-tetradecen-1-ol was identified among the components of the extract. The latter compound, an inhibitor of the aldehyde, has previously been shown to be present in the secretory gland of the insect.