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Mating behavior and factors affecting mating success of males were studied using wild Anastrepha ludens on a fieldcaged host tree. The most common courtship sequence had five components: (1) male calls from the underside of a leaf, (2) female arrives to the maleoccupied leaf, (3) male orients to female and stops calling, (4) one or both approach to a face-to-face position 1–3 cm apart, and (5) male mounts female after 1–2 s. Courtship behavior was almost identical to that of laboratoryculture flies observed previously under laboratory conditions. Most malefemale encounters occurred at a height of 1–2m, well inside the outer canopy of the tree. Differential mating success by males occurred. No male mated more than once per day, owing possibly to a very short sexual activity period. Factors favoring mating success of males were survival ability and tendency to join male aggregations and to fight other males. Thorax length and age (9–11 days difference) had no effects on male copulatory success. Overall win/loss percentage was not related to mating success because the males that were most successful at mating fought mostly among themselves, driving their win/loss percentage down. However, these successful males (at mating) won most of their fights against less successful males. Results confirmed a lek mating system: males aggregated, called, and defended territories; territories did not contain femalerequired resources; and females exercised mate choice, apparently through selection of sites within leks.

The application of insecticides is an essential component for eradication or management of fruit fly pests. Impact on nontarget organisms and public rejection of areawide pesticide applications have been major concerns in managing these programs. Bait stations have been proposed as alternative treatments in areas where broadcast insecticides are not acceptable. In this study, we defined bait stations as discrete containers of attractants and toxins, which are targeted at specific pests. Tests were carried out using the Mexican fruit fly, Anastrepha ludens (Loew), as the experimental insect. Our first bait station design was a sheet of sponge material fastened to a plastic peaked cover. Liquid bait consisting of protein hydrolyzate, sugar, adjuvants, a photoactive dye toxicant, and other additives was applied to the sponge. This station, when tested in an orchard, reduced sterile released adult populations by 70–90% in 4 d compared with check plots. Other tests in field cages showed that the bait station was ≈ap;22% less effective in killing adults compared with spot sprays on trees. We formulated a gelled bait by using a more refined hydrolyzed protein, supplemental attractants, feeding stimulants, and additives to protect the bait from drying. A series of experiments were carried out in field cages by using a cylindrical bait station that provided improved protection of the bait. These tests showed that there is a gradual decline in bait effectiveness with age.

The efficacy of photo active dyes as insecticides depends on the ingestion of the dye by the target insect and the activity of the dye at sensitive sites or on essential chemical functions. The site of this activity in insects is not understood, but we have found that certain chemical additives enhance the toxicity of phloxine B in the Mexican fruit fly. A series of tests with commercial adjuvants was performed under laboratory conditions that demonstrated a multifold decrease in the LD50 of phloxine B concentration and a decrease in the time required for photodynamic action to kill the flies. A total of 22 commercial adjuvants was tested. Of these, six were selected for evaluation under field cage conditions in comparison with a non-insecticide control bait (no treatment) and a phloxine B check bait with no adjuvant. Mortality was estimated by counting dead flies, feeding was estimated by fly counts at feeding stations, survival was estimated by trapping flies after the treatment period. In all cases the adjuvants increased the rate of mortality and decreased numbers surviving the treatment. Significant differences between adjuvants and both check and control were observed for mortality rates and the three best adjuvants, SM-9, Kinetic, and Tween60, induced significantly more mortality than the other adjuvants, the control, or the check. Feeding rates and survival rates indicated that the adjuvants increase the effectiveness of phloxine B in a predictable manner. The adjuvants appear to be active inside the insect rather than increasing the solubility of the dye in the bait medium. We propose that the addition of 1% vol:vol of the best adjuvant, Tween60 to the proteinaceous bait with 0.5% phloxine B will enhance toxicity as well as improve mixing and other characteristics of the bait.

The efficacy of photo active dyes as insecticides depends on the ingestion of the dye by the target insect and the activity of the dye at sensitive sites or on essential chemical functions. The site of this activity in insects is not understood, but we have found that certain chemical additives enhance the toxicity of phloxine B in the Mexican fruit fly. A series of tests with commercial adjuvants was performed under laboratory conditions that demonstrated a multifold decrease in the LD50 of phloxine B concentration and a decrease in the time required for photodynamic action to kill the flies. A total of 22 commercial adjuvants was tested. Of these, six were selected for evaluation under field cage conditions in comparison with a non-insecticide control bait (no treatment) and a phloxine B check bait with no adjuvant. Mortality was estimated by counting dead flies, feeding was estimated by fly counts at feeding stations, survival was estimated by trapping flies after the treatment period. In all cases the adjuvants increased the rate of mortality and decreased numbers surviving the treatment. Significant differences between adjuvants and both check and control were observed for mortality rates and the three best adjuvants, SM-9, Kinetic, and Tween60, induced significantly more mortality than the other adjuvants, the control, or the check. Feeding rates and survival rates indicated that the adjuvants increase the effectiveness of phloxine B in a predictable manner. The adjuvants appear to be active inside the insect rather than increasing the solubility of the dye in the bait medium. We propose that the addition of 1% vol:vol of the best adjuvant, Tween60 to the proteinaceous bait with 0.5% phloxine B will enhance toxicity as well as improve mixing and other characteristics of the bait.

The copulatory behavior of the male citrus mealybug, Planococcus citri (Risso), encompasses a complex hierarchy of responses elicited by sex pheromone and possibly other cues. The male is an early morning flier with a flight range of at least 183 m. The male's morning activity is influenced by a scotophase period; flight and response to females were curtailed when exposed to 6 h of light before testing. The response of males to females was partially resumed when kept in constant light for > 24 h. In the field, male phenology was restricted to periods when monthly mean temperatures exceeded 5°C.

One- to two-day-old Mexican fruit fly adults, Anastrepha ludens (Loew), were not deterred from feeding continuously or Jor periods of 1, 3, and 5 d on diet containing either 1 x 103 or 1 x 104 ppm cyromazine. Although flies behaved normally after feeding, egg production was significantly reduced. Cyromazine did not appear to affect males. Those females fed a single meal containing >1.5 x 103 ppm cyromazine had significantly fewer eggs compared with the control.

Aphytis melinus DeBach responded significantly more to green and yellow traps than to white, blue, fluorescent yellow, clear, black, or red; Scirtothrlps citri (Moulton) responded significantly more to fluorescent yellow, than to any of the other colored polyvinyl rectangular traps. A. melinus did not distinguish between opaque and translucent colored rectangles nor between different trap shapes. S. citri responded significantly more to translucent yellow and green than to opaque yellow and green. S. citri also preferred triangular, elliptical, and rectangular shapes over circular and square ones. Smaller traps were significantly more efficient in trapping A. melinus than the 386.1-cm2 rectangular traps; however, there was no significant difference between S. citri catches on the basis of number per unit area.

The pheromone glands of Aonidiella citrina (Coquillett) and A. aurantii (Maskell) do not appear until completion of the 2nd molt. The gross morphology of the glands is the same in the 2 species, but the glands differ cytologically.

Aonidiella aurantii (Maskell) infestations on ‘Navel’ and ‘Valencia’ orange fruit at the end of the calendar year were successfully predicted in the San Joaquin Valley based on data developed from catches of male scales in traps, female scales on twigs, and fruit infestations. Fruit infestations at harvest were regressed on the number of males trapped in the first, second, or fourth male scale flights or on the number of adult females on twigs. The equation that best explained the percentage of infested fruit as a function of male catches was a polynomial of the second degree. If the number of trapped males is known for the first, second, or fourth flights, the percentage of fruit infestation (≥1 scale per fruit) at the end of the season can be predicted. By regressing the percentage of fruit with ≥1 scale on that with ≥11 scales per fruit, a direct relationship to the flights was established. The citriculturist can select an acceptable action threshold by either recording total fruits with ≥:1 scale or patchy fruits with ≥:11 scales. Thus, the red scale pheromone trap can be incorporated as a valuable tool in the management of red scale populations.

Green and yellow were the most attractive colors to male and female Mexican fruit flies, Anastrepha ludens (Loew), followed by amber, orange, and fluorescent yellow, on colored rectangles in the laboratory and as colored solutions in McPhail traps in the field. The most attractive wavelengths were in the green and yellow spectral regions from 500–580 nm. Black, red, blue, and white were not more attractive than colorless control traps. Attractiveness of red, orange, and yellow doubled from spring to autumn in the field, whereas attractiveness of green and amber did not change. Yeast hydrolysate was significantly more attractive than any of the colors. Combinations of green or yellow with yeast hydrolysate in McPhail traps did not enhance the attractiveness of yeast hydrolysate. More flies were captured at 1 and 2 m above the ground than at 0.1 or 3 m (tree tops). More flies were captured on the north side of trees than on the south side, whereas east and west were not significantly different from each other.

Despite >40 yr of ecological and behavioral research on reproductive interactions involved in sterile insect release programs, experimental measurement of the intensity of intermale competition for mates and the role of sterile females in these programs has rarely been addressed. Experiments described in this study were designed to evaluate these factors. Virgin females from a mass-rearing strain (mass reared for 36 yr) of the Mexican fruit fly, Anastrepha ludens (Loew), were released and subsequently recaptured along with native Mexican fruit flies in natural habitats in Nuevo Leon, Mexico. Tests were carried out at six locations and replicated four times. Recaptured females were dissected to determine mating status. Data were analysed to determine whether the released females mated with native males, and to evaluate the influence of test site, test date, and wild male and female density on rates of recapture of the released females and their mating status. Results showed that 5–50% of the recaptured females mated with native males. This indicates that released females (even from a strain adapted to mass rearing) may occupy a significant amount of native male reproductive effort and that males in native populations have excess reproductive capacity. Number of native males captured per test was significantly correlated with the percentage of mated females. Plots of percent mating versus number of native males captured showed that when number of captured males was high, percent females mated was always high, but when numbers of males captured was low, percent mating could still be high. A severe freeze during the fourth test greatly reduced the native population. Released females were recaptured up to 7 wk after release and 4 wk after the freeze, indicating that the mass-reared strain had sufficient physiological-behavioral tolerance to survive extreme environmental stress.

An automatic applicator was developed to apply thixotropic adhesive to cards used in the detection, survey, and monitoring of small insects. One operator can prepare an average of 350 sticky cards per hour, which is 3.5-fold faster than using a hand wringer developed for the same purpose.

Two artificial larval diets were developed for the West Indian fruit fly Anastrepha oblique (Macquart). One was a papaya diet containing torula yeast, com flour, fresh papaya pulp, and sugar; this diet provided essential nutrients needed for larval development and produced sufficient numbers of flies for further testing. The other, a casein diet, included torula yeast, com flour, casein, sugar, minerals, and vitamins. The use of casein was a suitable replacement for papaya; pupal production increased 1.5 times. We reared A. oblique for 24 generations in papaya diet and 39 generations in the casein diet without loss of fecundity. Two other diets containing defatted soy flour or dehydrated pea powder in place of casein, produced similar numbers of pupae as the papaya diet. Raw or stabilized wheat germ inhibited larval development. When crude lipids were removed from wheat germ, recoveries of larvae, pupae, and adults were similar as in the casein diet. Addition of low amounts of Beck's salt mixture to casein diet increased adult recovery compared with the control, but salt concentrations >0.1% significantly decreased recoveries of larvae, pupae, and adults. Addition of vitamins to casein diet were not proven essential in the generation tested.

The effects of cyromazine on the adult Mexican fruit fly, Anastrepha ludens (Loew), include mortality and reduced fecundity and survival of the F1 generation. Dosage-dependent mortality was recorded for concentrations from 0.125 to 16%. Neonate to 2-d-old females fed an artificial diet with 5% cyromazine were incapable of laying eggs in fruit with a resistance of penetration >11 newtons. Laboratory observations showed that treated females could not insert their ovipositor into grapefruit rind. When the same females were given a soft substrate (parafilm membrane), they laid significantly fewer eggs than control females. The F1 generation of treated females developed significantly less in an artificial larval diet and in grapefruit in the field. A field test showed that grapefruit from treatments made with 5% cyromazine-NuLure mixture had significantly fewer larvae per fruit than the control. This difference did not occur with fruit from a 5% malathion treatment.

dross fragmented parts and cryostatic sections of female yellow scale, Aonidiella citrina (Coquillett), and the California red scale, A. aurantii (Maskell), were presented to males of the respective species. The pygidium of both females was the attractive area. Bioassays of dissected pygidial glands showed that these glands were the site of pheromone production.

The sex pheromones of the female yellow scale, Aonidiella cilrina (Coquillett), and the California red scale, A. auranlii (Maskell), were bioassayed for cross attraction in the labmatory by exposing live females and extracts of females of each species on the rotating wheel olfactometer. In the field, live females were exposecd in ice cream carton traps. In all tests, the 2 pheromones were specific, based on the response of the males.

Laboratory-reared adult males of Aonidiella aurantii (Maskell) (Homoptera: Diaspididae) were tagged by dusting the host lemons with Calco® oil blue RA dye just before emergence of the insects. Emerged males picked up the powdered dye on their bodies while they walked on the surface of the lemons before their initial flight. Tagged males released in the field were recaptured on cards coated with a 1:1 mixture of Stickem® and mineral oil and placed on traps baited with the sex pheromone produced by virgin red scale females. Each tagged male landing on the traps deposited dye which dissolved in the mineral oil on the cards, resulting in the formation of a distinct blue spot. The dye apparently had no effect on male emergence but did somewhat affect the flight and mobility of the insects. This technique offers several advantages over previously reported methods of marking small insects.