Formulations pheromone applications

Formulations and Equipment for Large Volume Pheromone Applications by Aircraft... 

The market for special control techniques that are appropriate for integrated pest management systems is closer to the scope of smaller companies where large-scale production facilities are not essential. Smaller companies have found unique niches in the pest management field, based often on particular expertise or experience. Controlled-release technology is an essential component for formulation and application of pheromones, therefore small companies have entered the market on the strength of this combination of expertise. Patent protection may be obtained to cover the devices and materials used to formulate pheromones, whereas the information relating to the composition of many pheromones is available in the open literature. 

The object of the work described here was to measure the amount and distribution of pheromone vapor in the air under woodland canopies after aerial applications of slow release formulations of disparlure, and the rate at which these declined with time. A limited number of experiments have also been done Z-9-tetradecenol formate (TDF), a mating inhibitor for the corn earworm moth (Heliothis Zea). 

New methods and apparatus are described for evaluating the pheromone release characteristics of controlled release formulations of All-tetradecenal both in the laboratory and following aerial application in the field. Laboratory release rates determined by these methods correlate well with rates observed in the field. 

The operating conditions were arrived at empirically by adjusting temperature, wind speed and illumination on a diurnal cycle until conditions were found which generated the same residual pheromone curve from a standard formulation in the tunnel as that formulation experienced in the field. For this standardization, one-eighth inch square Hereon flakes containing an average 13.3% TDAL by weight were used. This, as well as all other formulations, were tested, as nearly as possible, in the same form which they would have upon aerial application. They were either coated or mixed with a recommended sticker and measured aliquots were applied to rounds of filter paper. These were then mounted on racks in the test section of the tunnel. 

The final step in the testing program evaluates the performance of material aerially applied on small field plots. Since this procedure aims to define the physico-chemical characteristics of each product, not the biological effect, the following two processes are monitored 1. Residual pheromone from formulation collected in the field zero to forty days post application and 2. atmospheric concentration of TDAL in the forest canopy. 

Figure 7. Midday pheromone concentrations and temperatures at mid-canopy following aerial application of formulation A (500 g a.i./ha).

On the basis of laboratory and field results, the soluble acrylic system was chosen for further field trials. The formulation (code //1692) was tested on 210 hectares, 13 separate fields in Arizona and California during the 1982 growing season. Each test field was compared to a standard field, treated either with a chemical regime or a commercial pheromone product, located in the immediate vicinity. The efficacy assessment was based on trap catch reduction and boll infestation control. The treatment rate was 6.9 liters of formulation per hectare. This represented a rate of 3.7 grams pheromone and 36.9 grams pyrethroid per hectare. Treatment intervals were approximately ten days apart and the applications... 

Hall DR, Nesbitt BF, Marrs GJ, (ireen ASJ, Campion DG, Critchley BR. 1982 Development of microencapsulated pheromone formulations, pp. 131-143 in Insect pheromone technology chemistry and applications. ACS Symp Scr 190, Washington DC. 

Weatherston, I. (1990). Principles of Design of Controlled-Release Formulations. In Behavior-Modifying Chemicals for Insect Management Applications of Pheromones and Other Attractants, ed. Richard L. Ridgway, Robert M. Silverstein, and May N. Inscoe. New York Marcel Dekker. 

A more successful application of terpenes in crop protection has been found with the development of (4aS,7S,7aK)-nepetalactone 40 from catmint as an insect attractant. As well as luring male aphids, nepetalactone serves as an attractant to numerous aphid predators such as lacewings (Birkett Pickett 2003). Formulations of catmint oil distillate, impregnated into a polymer which releases nepetalactone over a period of months, are now commercially available. This represents the first example of plant cultivation on a large scale for insect pheromone production - less than 35 tonnes of plant material yield over 301 of nepetalactone-rich oil at a production cost of approximately l/g. 

Aggregation of the southern pine beetle, Dendroctonus frontalis. .. on loblolly pine (Pinus taeda) under beetle attack was not disrupted by aerial application of frontalure, which is a mixture of the attractant pheromone frontalin (195) and the host terpene a-pinene (230). Instead, aerial saturation with the pheromone in a heavily beetle-infested pine forest resulted in a rapid increase in the aggregation of beetles on pine trees undergoing attack (549). In this experiment, a ten hectare section of pine forest including 1.6 hectares of a D. frontalis infestation was treated twice by aircraft with rice seed soaked with frontalure. This formulation released virtually all of the frontalure within 24 hr (45 g/ hectare for the first application and 450 g/hectare for the second). 

Mitchell (597) has discussed the feasibility of using multicomponent formulations for control of several important pests of field crops. Hendricks et al. (600) showed that a mixture of looplure (622) and virelure (623, 624) were compatible and caught the cabbage looper (T. ni), the soybean looper (Pseudoplusia includens), and the tobacco budworm (H. virescens) on the same traps. It seems likely that pesticide applications to field crops could be greatly reduced by means of pheromone-baited monitoring traps, and such efforts will undoubtedly become a part of the integrated pest management projects now established by the Extension Service of the USDA. 

Brooks, T. W., and R. Kitterman Controlled release of insect pheromone formulations based on hollow fibers, and methods of applications. Paper presented at the June 26—29, 1977 meeting of the American Society of Agricultural Engineers. Available from Conrel Co., 110 A. St., Needham Hts., MA 02194. 1977. 

Use of Repellents Formulated in Specialized Pheromone and Lure Application Technology for Effective Insect Pest Management... 

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