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Relative-density estimates from two insect-sampling devices (sweep-net and shake cloth) were compared with absolute-density estimates for three size classes of the corn earworm, Heliothis zea (Boddie) (Lepidoptera: Noctuidae), and the fall armyworm, Spodaptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), in peanuts. Linear regression analysis indicated that medium and large larvae of corn earworm and all size classes of fall armyworm were consistently recovered by both devices (r2 ≥ 0.80). Small corn earworm estimates were poor for both devices (r2 ≤ 0.38).

Cultures of three soil plant pathogens were tested for their influence on transformation of hypopodes ofRhizoglyphus robini Claparede to the tritonymphal stage. Potato-dextrose agar (PDA) substrate was used to growBotrytis gladiolorum Timmermans,Curvularia trifolii f. sp.gladioli Parmelee and Latterell, andFusarium oxysporum f. sp.perniciosum (Hepting) Toole. Hypopodes were placed directly on the agar cultures of these fungi and on plain PDA. No significant differences were found in total number of hypopodes transformed or in rate of transformation.

The oviposition site selection of Tetranychus urticae Koch in response to fenvalerate and permethrin residues on soybeans was examined in the laboratory. Five leaf treatment regimes were evaluated on potted soybeans (half-area vs. whole area and partial coverage vs. complete coverage) plus a distilled water control. Over 95% of the eggs were deposited on untreated halves of leaflets on which the other half was treated with either fenvalerate or permethin. Similar oviposition behavior was observed for both partial spray coverage, ca. 10% of the leaf area, or total coverage of the treated half leaflet. Over 95% of the eggs were observed on the leaf surface in the control, whereas, 40% and 30% of the eggs were suspended off the leaf surface that was totally covered with permethrin and fenvalerate, respectively. No differences were observed in the vertical distributions of eggs between control, and the permethrin and fenvalerate half-leaf treatments. More than 95% of the total eggs were observed on the leaf surface; however, few eggs were laid on the leaflet half containing the pyrethroid residue.

Three replicated field experiments were conducted during 1972–73 to find insecticides or combinations of insecticides to control Keiferia lycopersicella (Walsingham) on tomato. Granular insecticides in general did not perform as well as most spray materials for reduction of tomato pinworm mines and larvae in tomato transplants. Acephate, diazinon, endosulfan, and methomyl kept seedlings nearly mine-free but greatest larval mortality was observed with azinphosmethyl, demeton, and phosalone. Chlordimeform was phytotoxic to seedlings but when sprayed alone or combined with Bacillus thuringiensis Berliner gave good pinworm control without phytotoxicity to field plants. In general, all insecticides applied as tank mixes reduced fruit loss by pinworm when compared to the check. Combinations containing acephate, leptophos, or methomyl provided superior control to combinations containing B. thuringiensis or carbaryl. No correlation was evident among leaves mined, presence of larvae, and fruit lost. Due to the larval habit of movement to new foliage and fruit, an active insecticide residue appeared essential to sustain damage free fruit.

Defoliation experiments were performed in order to provide information for development of a pest management simulation model for peanuts (Arachis hypogaea L.). ‘Florunner’ peanut plants were defoliated uniformly and nonuniformly at 9, 12, and 16 weeks after planting and harvested 2, 4, or 6 weeks following treatment. All defoliations resulted in lower stem weight to length ratios, lower pod numbers and weights, and equal or higher leaf numbers and weights. Defoliation altered the normal partitioning of photosynthate between plant parts. The location of defoliation damage (either uniform throughout the canopy or confined to the outer portion of the canopy) affected plant response in that plants defoliated nonuniformly grew more leaves in the 2 weeks following treatment than those defoliated uniformly

Two insect growth regulators (IGR's), ZR-619 (ethylin-methoxy-3,7,11-trimethyl-(2E, 4E)-2,4-dodecadienethiolate), and ZR-777 (Prop-2 ynyl 3,7,11-trimethyl-(2E, 4E)-dodecadienoate) were tested for potential use against the tomato pinworm,Keiferia lycopersicella (Walsh.) The IGR's were applied to cocoons and to soil where cocoons were formed. Both IGR's, alone and in combination, suppressed pinworn adult emergence from 23 to 7% when applied direct but were ineffective when applied to the soil. All treatments of IGR's in both methods of application reduced emergence of the parasitoApanteles sp. to 0% from levels as high as 61%. Use of the IGR's in this situation resulted in greater harm to potential biological control agents than in benefit to pest control.

Winter survival of pupae of the fall armyworm, Spodoplera frugiperda (J. E. Smith), was studied in relation to temperature and rainfall at 4 locations in Peninsular Florida. Moth emergence was greatest (51.0%) at Homestead, intermediate (27.5%) at Bradenton, and lowest (11.6%) at Sanford and Gainesville. The number of days required for emergence ranged from 15–35 and generally was greater for northern locations. Emergence of adults was positively correlated with mean soil temperature, and respective centigrade soil and air degree day values for emergence were 170 and 143.

The dispersal response of the twospotted spider mite, Tetranychus urticae Koch, to fenvalerate and permethrin residues on soybeans was examined in the laboratory. Both fenvalerate and permethrin elicited a significant dispersal response compared to dispersal of cohorts exposed to distilled water. Similar results were obtained with both whole - plant and excised leaf techniques. Dispersal was partitioned into walkoff and spindown responses. Spindown was the most frequent dispersal behavior (58%) of T. urticae exposed to fenvalerate, while both spindown (33%) and walkoff (23%) were observed at about the same frequency with permethrin residues. An inexpensive petri dish assay technique was developed which allowed numerous observations with limited input of labor.

Populations of Neoseiulus fallacis (Garman) and Phytoseiulus persimilis Athias-Henriot, predators of Tetranychus urticae Koch, were reared under homogeneous environmental conditions by inbreeding without introducing new germ plasm.Mites from 1-year-old inbred cultures had high mortality in all stadia and generally lower viability. Oviposition was reduced and a high percentage of eggs failed to hatch. Further inbreeding resulted in the production of only sterile female mites. These data cast serious doubt on the possibility of genetically improving populations of predaceous mites with only limited germ plasm resources.

A program for control of a leafminer, Liriomyza sativae Blanchard, on tomato was evaluated for its effect on crop yield and the target species in the spring and fall of 1974. Although populations of leafminers were much higher than is usually tolerated by producers, there was no evidence from regression model analysis of the data that leafminers directly affect yield. Consequently, in seasons when leafminer damage is less than complete foliage loss, applications of chemicals may be unnecessary.

The influence of larval host age on the levels of mortality and parasitization of the vegetable leafminer, Liriomyza sativae Blanchard, by Chrysonotomyia formosa (Westwood) and Opius dimidiatus (Ashmead) was determined by exposing separately host larvae of 3 ages (24, 72, and 120 h) in bean plant ( Phaseolus sp.) foliage to C. formosa and O. dimidiatus females for 24 h in the greenhouse. Host mortality and parasitization by C. formosa were significantly greater in 120-h-old larvae than in 24, and 72-h-old hosts. Host age and mortality were linearly correlated. Host age did not significantly affect parasitization by O. dimidiatus although higher levels were recorded for the 72-h-old host larvae.

Suppression of Tetranychus urticae Koch populations on strawberries by acaricides was studied during the 1969, 1970, and 1971 seasons. Classes of compounds used were cyclic carbonate, organic phosphate, chlorinated hydrocarbon, carbamate, formamidine, sulfite, and Organotin. Superior population suppression was achieved with cyclic carbonate, sulfite, and organotin compounds at 4 ounces active ingredient per acre. The poor performance of chlorinated hydrocarbon and Organic phosphate compounds in suppressing populations suggests field resistance is present in the mites.

Three fungicides (Daconil 2787® 75W, Difolatan® 4F, and Polyram® 80W) and 4 insecticides (carbaryl 4 LS, methomyl 90W, parathion 8E, and dimethoate 2.67E) were tank mixed in all combinations and sprayed on randomized plots of ‘Homestead 24’ tomatoes. In addition, 1 set of 4 plots was sprayed with Difolatan + parathion + TDE. Daconil 2787 gave the best control of gray leafspot. Dimethoate was superior to parathion for leaf miner control. Larval populations failed to reach levels where significant difference between the carbaryl and methomyl could be established. Considerable fruit damage was caused by the Difolatan + parathion + TDE combination. All other combinations were compatable physically. Carbaryl 4 LS caused slight foliage injury but neither fruit nor yields were affected significantly.

Carnation cuttings, set through 6X8 wire mesh in raised 3 ft wide beds of Leon sand ammended with peat, were grown under 25% natural saran shade cloth similar to commercial production. Plants were set and losses reset the first week of February. Weekly treatments by M-45 fungicide was applied for disease control. Populations of spidermites were allowed to develop until March 27 when acaricides were applied with a compressed air hand sprayer. Plots consisted of 36 plants or 12 sq ft of bed; each treatment was replicated 6 times. Samples consisted of 5 leaves/plot taken from the lower portions of the plant. Mites and eggs were counted under 10 x magnification on March 29, April 12, 24 and May 9. Five flowers were pulled from stems in each plot, placed in plastic bags, and mites extracted by shaking the flower heads in warm detergent water.

Tomato leaves soaked in solutions of 7 antimetabolite compounds were offered to larvae of Spodoptera eridania (Cramer) to determine whether these materials affect larval feeding and development. Thiouracil-treated leaves were not appreciably consumed by larvae, weight gain was poor, and only 1 adult was produced from 54 larvae fed this diet. Thiouracil apparently acts as a deterrent to larval feeding.

Six species of potted nursery plants infested with Rhizoecus americanus (Hambleton) were treated with 5 chemicals by dip, drench, foliar spray, and granular application to determine effective safe materials and the best method of application. Dip, drench, and granular treatments were superior to foliar sprays in reducing the population of mealybugs. Dimethoate, phorate, and methomyl were effective but phytotoxic to most species. Monocrotophos was effective and least phytotoxic.

Laboratory and field tests established that the adult tomato pinworm, Keiferia lycopersicella (Walsingham), is crepuscular (evening) in its mating habits. Approximately 75% of males captured in traps baited with female pheromone extracts and placed in tomato fields in February were caught during the twilight period (5-8 PM EST). Females exposed to an abrupt-transition photoperiod in the laboratory exhibited maximum calling activity 0.5 after lights-out, but males were responsive to female extracts throughout the night. Virgin pairs mated only during hours 1-3 of the laboratory scotophase. Females called most and males were most responsive to the pheromone in a laboratory olfactometer during the third night after eclosion. Males were more responsive when bioassayed with dim light both above and below the olfactometer than when there was light only from below.

Experiments were conducted on a commercial vegetable and ornamental transplant range in Sun City, FL during the 1977 fall and winter to determine attraction of various trap colors and to monitor leafminer dispersal into the range. Significantly more adult flies were captured on yellow traps than on yellow-green, orange, green and blue. Use of a protective transparent plastic bag on the yellow poster board traps had no significant affect on the number of adult flies trapped. Significantly more flies were trapped on cards located on the periphery of the range nearest the prevailing wind and within 100 ft of commercial tomato farms. Fly movement onto the transplant production range and infestation within production houses reflected both proximity of source and prevailing wind direction.

Phytoseiulus macropilis (Banks) was studied in the laboratory to determine its potential rate of population increase when fed on eggs of Tetranychus urticae Koch. The shortest developmental period was 4.7 days for males, and 5.8 days for females reared at 27 + 2?C and 90% + 5% RH under 12L:12D. Mean generation duration was 14.2 days with an average reproductive rate of 1.89 eggs per female per day. Predation of P. macropilis, expressed as the number of prey eggs consumed per individual, was 5.9 eggs for the immature stages and 194.1 eggs for the adult or 7.9 eggs consumed per adult per day. Mean adult longevity was 25.3 days. For each predator egg produced, 4.3 prey eggs were consumed. The intrinsic rate of predator population increase (r1,) was calculated as 0.27 individuals per female per day.

Seven foliar applied insecticides were evaluated for their effects on hemispherical scale on Ardisia. Four replications of each insecticide were applied with a hand sprayer to ca 10 inch high potted greenhouse grown plants infested with all stages of scales. Counts of live scale nymphs were made on two leaves per plant before treatment and at 7 and 14 days after treatment.

Seed heads of `DeKalb E-57' sorghum, planted on 26 April, 16 May, and 1 June 1976, were harvested in the soft dough stage and placed in emergence cages to determine the temporal pattern of emergence for the sorghum midge, Contarinia sorghicola (Coquillet), and its parasite, Aprostocetus diplosidis Crawford. Midge emergence began at the end of the milky stage, peaked 5-6 days later, and was complete in 10-11 days. Parasite emergence began 7-8 days after the end of the milky stage, peaked at 12-14 days, and was completed in 18-19 days. The emergence of the 2 insects overlapped from the 7th to 11th day after the end of the soft dough stage, Toxic residues of insecticides, applied to kill emerging adult midges, could be present for 7 days after the end of the soft dough without harming the adult parasites.

Three acaricides were tested for their effect on the twospotted spider mite population infesting neanthe bella palms in 3 in.pots in a greenhouse. Sprays were applied by handspraying until foliage was thoroughly wet. Five replicates were treated with each material and compared to an untreated check. Counts of eggs and mites were made on a 1 cm square of an infested leaflet. These counts were made before treatment and 1, 7, and 14 days after treatment.

Seasonal populations of the fall armyworm, Spodoptera frugiperda (J. E. Smith) and the velvetbean caterpillar, Anticarsia gemmatalis Hubner were surveyed during 1975-77 at Gainesville, Sanford, Bradenton, and Homestead, Florida. S. frugiperda was most abundant at Homestead during the spring and fall, and tended to be more numerous at the other locations during the summer and fall. A. gemmatalis larvae were present on soybeans at Homestead during all except 3 months of the study; populations peaked in the fall at all 4 sites.

Foliage mealybugs Phenacoccussolani group infesting purple passion plants were treated with five insecticides and numbers compared to those of untreated plants before and three, seven and 14 days after treatment. Counts were made on three leaves and the two internodal regions between them from each of five, one plant replicates. Insecticides were applied to foliage with a hand sprayer to the point of runoff. Plants were grown in containers under greenhouse conditions.

The population of beet armyworms, Spodoptera exigua (Hubner), in a chrysanthemum range near Ft. Myers, Florida, was simulated by a model based on the insect life history, the maximum and minimum temperatures, and light trap records. The increase in population with no treatments was similar to that observed at Red Rock, Arizona, and at Gainesville, Florida. Then the effect of insecticides on the life stages was superimposed in the model. With treatments, the populations could not be sustained at the original level. However, when migrant adults were added, the original populations were approximated. Thus, eggs from migrant moths place an unceasing demand upon the control program to insure plant protection and to maintain production.