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This laboratory study reports the ability of Formosan subterranean termite, Coptotermes formosanus Shiraki, colonies to survive for at least 9 yr while restricted to a sweater box. Colonies survived by limiting queen size and worker numbers, allowing these bonsai colonies to thrive. Queen physogastry appeared to plateau with 9-yr-old queens not larger than 6-yr-old queens, but nearly triple the size of 2-yr-old queens. Nine-year-old colony worker numbers were not greater than 6-yr-old colonies, but worker numbers were greater than in 2-yr-old colonies. Such colony survival under conditions of restricted resources provides a mechanism for re-infestation of areas following extensive area-wide control efforts. “Bonsai” colonies are relevant to the ability of marginalized colonies to avoid detection and then expand and invade into areas once the large, mature colonies are eliminated, and their potential to produce alates to start new C. formosanus colonies in areas which have been subjected to colony elimination programs impacts termite management strategies.

Experiments were conducted to determine the response of female oriental fruit flies, Bactrocera dorsalis (Hendel), and 2 fruit fly parasitoids, Fopius arisanus (Sonan) and Diachasmimorpha longicaudata (Ashmead), to the color, shape, and size of visual sticky traps. Numbers of females captured on yellow spheres increased as sphere size increased with diameters of 5–11 cm. Preference of females for yellow spheres over green and red spheres was positively correlated with sphere size. Yellow-colored spheres and rectangular blocks of equivalent surface area were equally attractive to females; however, females were more attracted to red spheres than to red blocks of equivalent surface area. The influence of background colors on the attractiveness of spheres was investigated by comparing the response of flies to 8 color combinations of the panels and spheres of Ladd traps. Standard Ladd traps, with red spheres attached to the center of yellow panels, captured more females than any other trap tested and could be used to monitor populations of oriental fruit flies in orchards. Female oriental fruit flies may be attracted to standard Ladd traps because of the visual contrast of red spheres against a light background.

Bioassays were performed to test the responses of the Formosan subteranean termite, Coptotermes formosanus Shiraki, to dichloromethane extracts of whole Iridomyrmex glaber (Mayr) workers. Termite workers were strongly repelled by filter papers treated with I. glaber extracts. In a choice test, termite workers fed significantly less on filter papers treated with I. glaber extract compared with solvent-treated controls within a 24-h period. Bioassays also were performed to evaluate the effect of different concentrations of ant extract on termite tunneling behavior. The rate at which termites penetrated the treated sand was concentration dependent. In 10 d, termites failed to penetrate any of the sand barriers treated with either 250 or 500 ant equivalents per gram of sand. Our results suggest that ant semiochemicals are a potential source of natural products that could prove useful for termite control.

Field shldies were conducted during 1983-1986 to determine damage thresholds for western corn rootworm, Diabrotica virgifera virgifera LeConte, adults feeding on silks of inbred lines of dent corn, Zea mays L., grown under seed-production field conditions. Three inbred genotypes were used as pollen sources and three others as female plant material to assess beetle impacts. Beetle densities of one to three beetles per ear reduced kernels per hectare and kernels per kilogram, increased round kernel fractions, and decreased flat fractions for all genotypes. With simulated seed-production field conditions, effects due to distance between male pollen source and receptive female ear (row effects) did not influence beetle damage thresholds across blocks of female corn. Environmental stress and plant genotype influenced impacts of beetle density. Conditions of moishue or heat stress during pollination magnified beetle feeding effects. Abundant pollen levels also reduced impacts of beetle feeding. Regression equations for prediction of kernels per hectare as influenced by beetle density were calculated.

Inheritance of resistance in maize, Zea mays L., to oviposition by the maize weevil, Sitophilus zeamais Motschulsky, was investigated by first crossing 10 inbred lines (A619, B37, B68, B73, H9S, Mo17, N28, Pa91, R80S, and T220) in all possible combinations (full diallel) in two environments (Florida and Kentucky). Resulting F1 seed was evaluated for resistance to the maize weevil. Remnant F1 seed was then planted, and the F2seed was evaluated for resistance as before. A significant environmental influence occurred on the expression of resistance; maize grown in Florida was consistently more susceptible to maize weevil attack than that grown in Kentucky. Generally, however, the most resistant genotypes in one environment were among the most resistant in the other. Other findings indicated that general combining ability and, to a lesser extent, specific combining ability were important in the heritability of resistance to the maize weevil. A significant maternal effect occurred on resistance in the F1 but it generally was not present in the F2. seed. Conclusions are that, using these genotypes, development of hybrids with significant maize weevil resistance should be possible because the resistance factors were principally influenced by general combining ability and maternal effects were not expressed past the F1 generation.

Monoterpenoids are potentially useful for the development of new insecticides because of their low mammalian toxicity. Different monoterpenoids differ significantly in their toxicity to particular insects. We evaluated the toxicity of 6 monoterpenoids, 2 alkaloids, and 1 hydrocarbon that are plant or ant semiochemicals to the Formosan subterranean termite, Coptotermes formosanus. Bioassays were performed to determine the effects of the semiochemicals on the mortality and tunneling behavior of termites and the fumigant activity of 3 monoterpenoids, citral, geraniol, and eugenol. We also tested the effect of the monoterpenoid alcohol eugenol, as a feeding deterrent. We found significant differences in the termiticidal activity of the different compounds tested. Monoterpenoid alcohols, particularly eugenol, were the most effective as termiticides against C. formosanus. Eugenol was also more effective as a fumigant than citral and geraniol. In addition, termites did not tunnel through eugenol and geraniol-treated sand barriers for at least 5 d. However, eugenol was not effective as a feeding deterrent when applied directly to blocks of wood, except at the relatively high concentration of 100,000 ppm.

Ixodid ticks collected by the junior author (White 1949) incidental to a survey in Jackson County, Mississippi, were forwarded to the Rocky Mountain Laboratory, Hamilton, Montana, for examination for disease agents. Jackson County is the most eastward of the three coastal counties of Mississippi. In all, five species of Ixodidae were collected between 25 August 1947 and 28 May 1949, but disease agents were recovered in only the two most prevalent species in collections, namely, Amblyomma americanum (L.) and A. maculatum Koch. The results of these tick tests are the subject of this report. 4