Monday, August 31, 2015

Pheromones play a big role

Pheromones play a big role in the insect kingdom. The surveillance of native species of stored product insects (personal communication — A. J. Gilbert, Calif. Dept. of Agric.). In this preliminary test the traps were found to be attractive to both adults and larvae of beetles from the Dermestidae and adults of Curculionidae, Cucujidae and Tenebrionidae in sizable numbers, while adults of Bostrichidae, Nitidulidae, Ostomidae and Mycetophagidae were captured in small numbers. The ratio of adults in the traps was: 2.7(A): 2(B): 2.5(C): 1(D). The ratios of 338 larvae caught were: - 3.6(A): 2.6(B): l(C): 1.4 (D). 

The structure of the pheromone trap appeared to provide an ideal hiding place for the insects. The traps with insecticide only had an average of two and one half times the number of adult insects of all families when compared to the untreated control. Concentration of pheromone appeared to be too low in these tests, but it was interesting that no larvae other than dermestid larvae were caught in the traps; that 98.2% were Atta- genus sp. and of these 47.6% were caught in the megatomoic acid traps. This suggests, contrary to our expectations, that Attagenus sp. larvae are stimulated by megatomoic acid. Check out pheromones at https://jail6letter.wordpress.com/2015/03/17/your-pheromones-matter-to-her/

22. 9.2. Lepidoptera

Pheromones make insects die. In the work with Lepidoptera, cis-9, trans-12-tetradecadienyl acetate was isolated and identified as the principal component of the sex pheromone of the almond moth, Cadra cautella (Walker) and the Indian meal moth, Plodia interpunctella (Hiibner) (Brady et al. 1971a; Kuwahara et al. 19713). It has also been isolated from the Mediterranean flour moth, Anagasta kiihniella (Zeller) (Brady et al. 1971b; Kuwahara et al. 1971b), the tobacco moth, Ephestia elutella (Hiibner) (Brady and Nordlund 1971) and the raisin moth, Cadra figulilella (Gregson) (Brady and Daley 1972). Small-scale tests using this compound were conducted in an isolated and dark room (42.4 m3) using four traps (one liter volume paper cylinders with open ends, coated inside with a sticky compound) treated with 10 ng of the compound, and one control (Brady et al. 1971a). In tests with Plodia interpunctella, an average of 4 % of males released in the darkened room were trapped. In similar tests, an average of 27% of Cadra cautella males released were trapped.


In a more extensive study, the pheromone was used in three separate buildings known to be infested with stored food moths (personal communication, D. Grant, Zoécon Corporation). Eleven traps, each baited with 0.2 u of the synthetic phero- mone in a polyethylene cap, and four control traps, were distributed about 7 m and 2.5-3 m above the floor in the three buildings. Four species of moths were cap- tured in these traps: Plodia interpunctella; Ephestia elutella; Cadra figulilella and C cautella. All moths in a representative sample were males except for the raisin moth (130 males and one female). In contrast, a sample of 60 Cadra sp. taken in a light trap contained a 1.5 :1 ratio of males to females. The light traps captured more moths than the pheromone traps (1.321) but they were more expensive and_more difficult to set up and maintain. The pheromone traps placed at high levels caught action.

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