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Foliage of the potato, Solanum tuberosum (L.), was analyzed previously to determine its nutritional content. This information was used to help develop a meridic diet for rearing the Colorado potato beetle, Leptinotarsa decemlineata Say. Various test diets were prepared, and types and concentrations of proteins, amino acids, carbohydrates, and ascorbic acid were tested for their influence on growth and weight gain of larvae reared from the egg stage on diet. At 2.8% protein or less, neither egg albumin nor casein produced adult beetles. Adults were reared with casein concentrations of 3.0 and 4.2%, but not at 5% casein. An abbreviated list of foliar amino acids was as effective as the complete foliar complement in the rearing of adults. Oat flour or potato flakes were suitable carbohydrate sources for rearing to the adult stage. The composition of a meridic diet is presented which was used for rearing the Colorado potato beetle from the egg to the adult stage, in the absence of host plant material.

Three mark–recapture experiments were conducted to determine patterns of movement in the Colorado potato beetle, Leptinotarsa decemlineata (Say), over an agricultural landscape in Maryland. In the 1st experiment, beetles were released from a central point and recaptured 5–20 d afterward in potato trap fields extending outward in 4 compass directions to a maximum distance of 0.65 km. Approximately 30% of released beetles were recaptured. Recaptures declined rapidly with distance, and a few beetles were recaptured 0.65 km from the release point after 5 d. A stream and a dense winter cover crop may have acted as impediments to movement over part of the experimental area. In the 2nd and 3rd experiments, beetles were released at various distances in 4 compass directions from a central “trap” field and recaptured 5 d later. Recapture rates were = 20% when beetles were released at 50 and 100 m and 6.5% when released at 300 m. Direction of release was a significant variable in the recapture rate in one of these experiments but not in the other. The results suggest that effective field rotation to reduce beetle population densities from year to year will require a distance of ≥0.5 km.

The glycoalkaloids solanine, chaconine, leptine I, leptine II, solasonine, solamargine, and tomatine, synthesized in the foliage of variousSolanum species, were tested in synthetic diets for their effects on potato leafhopper adults,Empoasca fabae (Harris), at concentrations of 0.03%, 0.09%, and 0.27%. Percent mortality was recorded after a 72 hr feeding period. At the lowest concentration (0.03%), tomatine in the diet resulted in the highest adult mortality (95%) with mortalities ranging from 10% to 41% in the other glycoalkaloid diets. At the highest concentration (0.27%) mortalities ranged from 69% to 100% with no significant (P>.05) differences among the diets. Mortality varied the most among the glycoalkaloid diets at the 0.09% concentration. Chaconine, ubiquitously found with solanine inSolanum tuberosum L., caused significantly (P≤.05) higher mortality (59%) than did solanine (8%). Mortalities with solasonine and solamargine in the diets (55% and 54%, respectively) were not significantly (P>.05) different from the mortality with chaconine in the diet. Including leptines I and II in diets resulted in lower mortalities (28% and 30%, respectively). Mortality was significantly (P≤.05) the highest (97%) with tomatine in the diet.

The foliage of the potato Solanum tuberosum (L.)was analyzed to gain understanding of the within-plant distribution of the Colorado potato beetle, Leptinotarsa decemlineata Say, and to develop a synthetic diet useful for rearing of this insect for experimental purposes. Foliage from three age classes was analyzed for protein, amino acid composition of protein, free amino acids, sugar, starch, nonstarch polysaccharides, dietary fiber, and trace elements. Concentrations of the amino acids glutamine, serine, asparagine, glutamic acid, proline, histidine, and arginine were higher in the youngest foliage than in the two older categories. Protein content was highest in the youngest foliage. With the exceptions of copper and phosphorus, the oldest foliage had the highest mineral levels. Concentrations of sugars were highest in the oldest foliage. The concentrations ofnonstarch polysaccharides tended to be lowest in the youngest foliage.

The Colorado potato beetle spiroplasma, a helical wall-less bacterium, attaches to the midgut of larval and adult Leptinotarsa decemlineata (Say). Despite its lack of pathogenicity to the beetle, its host specificity and ease of transmission may prove useful in biological control if insecticidal genes (e.g. the Bacillus thuringiensis subsp. tenebrionis δ-endotoxin gene) can be incorporated into its genome. Toward this goal, Colorado potato beetles were collected from various sites in North America and examined for spiroplasmas. Spiroplasmas were observed in the gut contents of L. decemlineata adults collected in Canada (Alberta and Quebec) and the United States (Arizona, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Jersey, New Mexico, New York, North Carolina, Utah, and Washington) and from L. texana Schaeffer adults collected in Texas. None were naturally associated with adults of the related species, Doryphora quadrasignata Germar, collected in Brazil. Seven isolates adapted to insect cell-free media are now available for molecular studies.

Controlled environment experiments were used to determine the effect of light intensity on levels of glycoalkaloids and resistance to the Colorado potato beetle (CPB),Leptinotarsa decemlineata Say, inSolanum chacoense Bitter clones that synthesized acetylated glycoalkaloids, the leptines. Plants were grown under two light intensities, 50 or 250 ώmol m-2S-1, and bioassayed for CPB resistance by placing neonate larvae on excised foliage. Larval development stage and mortality were recorded after four days. The leptine-synthesizing clones responded to the increase in light intensity with a 2–4 fold increase in level of foliar leptines. Larval development rate on foliage from plants grown under high light intensity was reduced and larval mortality increased. Results showed a significant (p>0.05) effect of light on glycoalkaloid synthesis and CPB resistance.

Knowledge of the location of Lycoriella mali (Fitch) in mushroom-growing medium throughout the insect’s life cycle may enable mushroom growers to direct control efforts where the insects are concentrated, thus reducing control costs and insecticide usage. Compost and casing, exposed to a laboratory colony of L. mali , were divided into several horizontal layers by nylon netting that did not inhibit insect movement. At regular intervals (3-5 d) after exposure to L. mali , each layer of medium was extracted to determine the number and stage of insects in the layer. Insects were extracted from the medium by screening, differential sucrose densities, and centrifugation. Females penetrated the compost to a depth of 5.7 cm to oviposit, but most eggs were laid at 1.9-3.8 cm. As larvae hatched and matured, most moved deeper into the compost. Late fourth instars or pupae migrated to the upper level of the compost. Very little movement into casing occurred when the compost was infested before casing was added; infestation of casing resulted from exposure of the medium to flies after the casing was added. Results indicate that directing control efforts to the upper few cm of compost would provide the greatest return for the effort.

When diazinon was incorporated into compost used to grow mushrooms at rates of 0, 12.5, 25, 50, and 100 ppm, control of Lycoriella multiseta (Felt) averaged 0, 37, 67, 89, and 95%, respectively, and control of Megaselia halterata (Wood) averaged 0, 95, 98, 99, and 100%, respectively. Yield of mushrooms from beds treated with 0, 25, 50, 100, and 200 ppm of dlazlnon were not affected significantly, but the size of an individual mushroom increased with increasing doses to 100 ppm. Residues of diazinon in the mushroom averaged 0.01 ppm or less, and no differences in flavor between treated and untreated mushrooms were detected.

Comparisons were made between uninfested adult Mexican bean beetles and those infested with the ectoparasitic mite Coccipolipus epilachnae Smiley. No significant differences were found based on longevity, fecundity, or food consumption of beetles fed lima beans and held at 22°C on a 16 hr light - 8 hr dark day.

Lycoriella mali (Fitch) populations were exposed to mushroom compost that contained mushroom mycelium growth of various ages to determine whether the suitability of the compost for fly development was affected. It was found that unspawned compost was infested by flies and other invertebrate pests and that the more the compost was colonized by mushroom mycelium, the fewer the L. mali produced. The reduction in flies was greatest after 12 days of mycelium growth. The type of compost apparently affected its suitability for fly development. Also, freshly made compost was less suitable for L. mali than aged compost. Large numbers of mites and nematodes were associated with fly infestations. This demonstration of the vulnerability of uncolonized mushroom compost to invertebrate pest attack could explain the variation in pest populations among different mushroom-growing facilities.

Field tests were conducted to determine the effectiveness of an experimental preparation ofBacillus thuringiensis var.thuringiensis against Colorado potato beetle infestations on potatoes and tomatoes. Applications were made weekly with a tractor-towed commercial sprayer at the rates of either 473, 946, or 2,838 ml. ofB.t.t. in 378.41 of water per 0.4 hectare. Significant reductions were observed in treated plots of all stages of the beetle. All untreated plants were completely defoliated by the end of the test due to beetle feeding. No significant differences were observed among the different treatment levels.

In laboratory tests conducted to determine the effectiveness of the exotoxin ofBacillus thuringiensis against the Colorado potato beetle,Leptinotarsa decemlineata (Say), applications sprayed on tomato foliage at dilutions ranging from 10−1 through 10−4 killed 90% of the 1st and 2nd stage beetle larvae. As the dosage decreased, the time to achieve this level of mortality increased from 4 to 9 days. Adult beetles were not killed by these treatments; however they did cease feeding. In field tests, the highest dosages ofB. t. sprayed on either tomato or potato plants provided adequate or nearly complete protection when applied weekly. Young larvae that ingested sub-lethal doses developed into adults with atrophied mouthparts and antennae, transformations of the paired parts of the labial palps into an unpaired part, the appearance of a tarsal-like claw on a palp, and malformation of the cranial sclerities.

The volatile components (ppm of total solids) emitted by corn silk were found to be l‐butanol (1), 1‐pentanol (7), 1‐hexanol (1), (E)‐4‐hexen‐1‐ol (4), 3‐methyl‐1‐butanol (1), acetaldehyde (5), hexanal (4), 2‐furancarboxaldehyde (furfural) (2), and phenylacetaldehyde (12). Phenylacetaldehyde was found to attract the corn earworm, European corn borer, soybean looper, tarnished plant bug, Cisseps fulvicollis, and forage looper. Combining phenylacetaldehyde with butanol or acetaldehyde increased attractiveness to some species; other combinations reduced attractiveness.

The role of leptine glycoalkaloids in resistance to Leptinotarsa decemlineata (Say) was studied with Solanum chacoense Bitt. clones that had been selected for extremes of leptine level. Three high-leptine (120–306 mg/100 g fresh weight) clones, one from each of three accessions, were compared with three low-leptine (0–51 mg/100 g) sib-clones for number of adults and feeding damage in the field, adult feeding rate on leaf disks, and larval development on detached foliage. Number of adults per plant on the six clones ranged from 1.5 for the clone with the highest leptine level (306 mg/100 g) to 37.5 for a clone lacking even a trace of these rare glycoalkaloids. There were also wide and significant differences among the six clones for adult feeding damage, adult feeding on leaf disks, larval development rate on detached foliage, and survival to adult eclosion. Differences between the high- and low-leptine clone from each accession were significant for all five resistance parameters, and these differences appeared to be directly related to the concentration of foliar leptines.

The fragrant chemical compound volatilized by the bladder flower, Araujia sericofera Brot., was identified as phenylacetaldehyde. It attracted many economically important species of moths, and when it was used with a blacklight trap, it increased trap collections of pest moth species by 48%.

Blacklight traps were operated for 43 months at a density of 3 per square mile on an isolated tropical island, St. Croix, U. S. Virgin Islands, to determine the effect on populations of 25 insect species. Subsequently, the density of traps was reduced to 0.3 per square mile for 18 months, and changes in the collections were noted. The test species were: Agrius cingulatus (F.), Callionima ramsdeni (Clark), Eumorpha vitis (L.), Hyles lineata (F.), Manduca rustica harterti (Rothschild), Manduca sexta (L.), Xylophanes pluto (F.), X. tersa (L.), Heliothis virescens (F.), H. zea (Boddie), Ecpantheria icasia (Cramer), Gryllus assimilis (F.), Microcentrum triangulatum Brunner, Neoconocephalus triops (L.), Schistocerca pallens (Thunberg), Acrosternum marginatum (Palisot De Beauvois), Loxa pilipes Horvath, Nezara viridula (L.), Jadera rufofusca Barber, Bothynus cuniculus (F.), Phyllophaga microphylla Moser, P. portoricensis (Smyth), Calosoma alternans alternans (F.), Conoderus sp. and Lacon subcostatus (Candeze). Many species had decreased populations as measured by BL trap collections during the 43 months, and within a year after the trap density was reduced most had surges to population levels as high or higher than those recorded during masstrapping. Lepidopteran population indices were more affected than indices of other orders. Generally, most decreases and increases in populations appeared to be related to the trapping, but the numbers of some species that were removed by the traps were so low that any effect was indirect. Blacklight traps have a potential as a supplement for other control measures or possibly as a control themselves if the trap area is sufficiently large or sufficiently isolated.

The strong phototactic response of many insect species to blacklight (BL) has encouraged considerable study of means to use this phenomenon to control insect pests. This paper lists and provides references for all of the known published efforts to control natural populations of insects with black light traps. The usual approach in a control effort has been to combine the BL lamp with a collection device to form a trap. Many designs have been used for control and survey purposes (Hollingsworth et al. 1963, Hollingsworth 1967, Tashiro et al. 1967) but most are similar to that described by Harding et al. (1966). Occasionally the attraction of the lamp is supplemented with pheromone (Gentry et al. 1971, Cantelo et al. 1972) or the efficiency of the trap is increased by using an electrically charged grid around the lamp (Taylor and Deay, 1950, Beaty et al. 1951, Noble et al. 1956). The results of the control experiments have been variable, as can be seen from the table.

A sensitive test was sought that could be used to detect small differences in resistance to the Colorado potato beetle (CPB) in Solanum species. Three tests were evaluated and compared. One test compared adult CPB foliage consumption of leaf disks from a susceptible potato cv, S. tuberosum, with disks from two S. chacoense clones. The second test compared weight gain on foliage from the three plants by 4th instar larvae and the third test compared larval development rate and mortality. With sufficient replication all three of the tests could detect significant differences between each of the test clones. The most sensitive test measured the stage of development of neonate larvae after feeding on test plants four days. This test required only four replicates to detect a 50% difference from the overall mean assuming an alpha level of 0.05 and a beta level of 0.10.

Methods used in breeding and selecting potatoes for resistance to Colorado potato beetle, green peach aphid, potato aphid, and potato leafhopper are reviewed. Sources of resistant germplasm, the nature of resistance, breeding behavior of resistance factors, and methods used to measure resistance are discussed. Specific problems encountered in breeding insect-resistant potatoes are discussed in relation to early-generation selection procedures.

In tests conducted to determine the stability of selected insecticides in compost used to grow mushrooms, 3 ureide insecticides, diflubenzuron (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide), BAY SIR 8514 (2-chloro-N-[[(4-trifluoromethoxyphenyl)amino]carbonyl]benzamide), and Lilly 7063 (N-[[[5-(4-bromophenyl)-6-methyl-2-pyrazinyl]amino]carbonyl]-2-chlorobenzamide), were much more stable than the 3 phosphorus-containing insecticides tested, diazinon, ethoprop, and chlorpyrifos, although chlorpyrifos provided up to 80% fly control for 6 weeks. Residues were assayed by means of both an established bioassay with a sciarid fly, Lycoriella mali (Fitch), and with a newly developed chemical method based on high performance liquid chromatography.

Sprays of Bacillus thuringiensis subsp. thuringiensis (B.t.t.), which contained the beta-exotoxin, were applied to small-scale field plots of tomatoes infested with the Colorado potato beetle [Leptinotarsa decemlineata (Say)] and to bean plots infested with the Mexican bean beetle (Epilachna varivestis Mulsant). Two parasitic wasps of the family Eulophidae were used in conjunction with the B.t.t. in an effort to reduce beetle populations. Treatments on tomatoes consisted of either B.t.t. alone, B.t.t. plus releases of the egg parasite Edovum puttleri Grissell, E. puttleri releases alone, or untreated controls. Treatments on beans were similar except the larval parasite Pediobius foveolatus (Crawford) was released instead of E. puttleri. Treatments in which B.t.t. was used, either alone or in combination with the parasite, significantly reduced adults and 3rd and 4th instar larvae of both species of beetles. The egg parasite, E. puttleri, was unable to significantly reduce the CPB population by itself, however P. foveolatus was able to significantly reduce both 3rd and 4th instar larval and adult populations of the MBB.

The potential bacterial mutagenicity of the beta-exotoxin of Bacillus thuringiensis var. thuringiensis was detennined by the Salmollella-microsomal assay (Ames test) and found to be nonmutagenic. The activity of three experimental preparations of B. thuringiensis var. thuringiensis were determined by feeding the preparations to house fly larvae and to neonateColorado potato beetle larvae, Leplinotarsa decemlineala (Say). Comparisons with controls were made as to food consumption and mortality rates, and the LDIOthrough LDQ, were calculated. In field tests of 0.05-ha plots of potatoes, an experimental preparation of B. lhuringiensis var. lhurillgiellsis provided excellent control of the Colorado potato beetle when applied weekly at the rate of 1,892 ml/O.4 ha.

Significant differences were found in larval development rate and mortality of Colorado potato beetle,Leptinotarsa decemlineata (Say), among nine wild, tuber-bearingSolatium species by placing neonate larvae on detached leaves.S. pinnatisectum Hawkes, 5.polyadenium Greenm., andS. trifidum Corn restricted development the most, 5.berthaultii Hawkes was intermediate, andS. canasense Hawkes,S. demissum Lindl.,S. megistacrolobum Bitt.,S. spegazzinii Bitt., andS. tarijense Hawkes restricted development the least. All tested species restricted development more than did the cultivar Kennebec. The measure of larval development rate and mortality was weakly correlated with foliar defoliation in field tests based on species-accession means (r= + 0.6, P

For chemical control of the sciarid fly, Lycoriella mali (Fitch), attacking the commercial mushroom crop only methoprene or malathion can be used as a treatment of the casing. Twenty-four chemicals were evaluated to find more effective materials and to determine lengths of activity and effects on a mushroom crop when used in commercial conditions. The LD95 of the more effective materials, based on ppm of dry weight of casing, was chlorpyrifos-56, diflubenzuron-120, dimethoate-88, ethoprop-81, methoprene-104, and SIR 8514-5. Methoprene, diflubenzuron, and SIR 8514 did not reduce yields as casing treatments whereas chlorpyrifos and ethoprop did. Diflubenzuron and SIR 8514 when used at several times efficacious dosages had no deleterious effect on mushroom yield. A treatment of the casing with diflubenzuron or SIR 8514 should eliminate fly infestations from the casing for the entire cropping period.

This study was designed to determine if results of insecticide tests were affected by size and location of field plots used. Population density of insects in plots treated with carbaryl varied with plot size. Feeding damage by the potato leafhopper, Empoasca fabae (Harris), to potato foliage dropped rapidly as the treated plot size increased from 4 to 99 m2 and then continued to decline gradually to 1,000-m2 plots. Thus, a plot of ca. 100 m2 may be the minimum size to accurately determine insecticidal effect on the potato leafhopper. Corn earworm, Heliothis zea (Boddie), egg numbers changed the most sharply as plot size increased from 3 to 31 m2. Larval numbers dropped most sharply when plot size was increased from 3 to 14 m2. A minimum plot size of ca. 30 m2 appears to be necessary for corn earworm infesting sweet corn for tests done under similar conditions. Taylor’s index of aggregation and Lloyd’s mean crowding index and patchiness index were calculated for potato leafhopper injury in potatoes, caterpillar feeding damage in sweet corn ears, and numbers in sweet corn plots of Orius insidiosus (Say), Coleomegilla maculata (De Geer), corn earworm eggs and larvae, and European cornborer larvae, Ostrinia nubilalis (Hubner), in treated and untreated areas of plots.

A natural population of corn earworm, Heliothis zea (Boddie), larvae was labeled with P32 as they developed on corn injected with the isotope. The movement and distribution of emerging adults was then studied through the use of a series of virgin-female traps and light traps. The labeled adults dispersed themselves in a non-random manner, seeking out and concentrating themselves in and near small plots of corn which was in a suitable stage for attack. Population estimates based on the recapture of labeled insects indicate that St. Croix is a suitable location for suppression programs.

The rate of disappearance of a 0.1% aqueous sodium Fluoresce in solution after being sprayed on adult male and female Manduca sexta (L.) and subsequently exposed in the laboratory, in the field, and in light traps was compared by spectroflnorometry. Also, when 1710 similarly marked male moths were released over a 2-month period on the island of St. Croix, 4.3% were recaptured in light traps. The fluorescein tagging proved effective and more sensitive than oil paint as a marker for the tobacco hornworm.

Incorporating diazinon into the compost media in which mushrooms are grown is widely practiced to control three dipteran pests, namely, Lycoriella mali (Fitch) and L. multiseta (Felt) (Sciaridae) and Megaselia halterata (Wood) (Phoridae). However, there were indications at times that diazinon-treated compost had lower yields than untreated compost. To determine if the lowered yields were due to differences in sensitivity to diazinon of the different strains, eight commonly used strains were grown in treated and in untreated compost, and the yields were compared. Four strains had significantly lower weights when treated with diazinon, and three of these had significantly fewer mushrooms. The weight of the most sensitive strain was reduced by 30% and the number by 26%. The treatment also delayed the appearance of the growth flushes in sensitive strains. Poor cultural practices tended to result in increased phytotoxicity. There was no difference among the strains in the quantity of diazinon translocated from the compost to the fruiting bodies. The maximum recorded was 0.027 ppm, and most samples contained less than 0.01 ppm.

Six of 29 chemicals evaluated against a sciarid fly Lycoriella mali (Fitch), the major insect pest of commercial mushrooms, gave control equal to that of diazinon at lower doses. Those found to require less and their LD95 and LD50 (ppm), respectively, were: BAY SIR 8514 (2-chloro- N -[[[4-(trifluoromethoxy) phenyl]amino]-carbonyl]benzamide) (0.4, 0.001); chlorpyrifos (11.0, 1.5); Lilly L-7063 ( N -[[[5-(4-bromophenyl)-6-methylpyrazinyl] amino] carbonyl]2-chlorobenzamide (21.2, 3.8); ethoprop (25.1, 12.3); dimethoate (37.9, 7.3), and diflubenzuron (49.2, 4.9).

Ethanol extracts of the glandular hairs, leaves, or fruit of the tomato plant were found to contain materials repellent to the adult female and the immature forms of Tetranychus urticae Koch and T. cinnabarinus (Boisduval), but not to the adult males of these species, nor to the adult females of T. turkestani Ugarov and Nikolski. The repellent had a half-life of ca. 1.7 h.

Chemical methodology based on liquid chromatography was developed to measure trace amounts of two insect chitin synthesis inhibitors in mushrooms that are effective for control of a sciarid fly, Lycoriella mali (Fitch). No residues (

An experimental preparation of Bacillus thuringiensis Berliner var. israelensis (Goldberg) tested against a sciarid fly Lycoriella mali (Fitch) in mushroom compost gave over 90% control. The LC95 was one part B. thuringiensis var. israelensis to 696 parts water (wt/wt); the L95 was one part B. thuringiensis var. israelensis to 64 parts water. With a 1:60 dilution, the mortality exceeded 99.5%. Two commercial preparations containing B. thuringiensis var. israelensis tested at a dilution of 1:100 produced mortality rates of either 79.2 or 94.4%.

A preparation of Bacillus thuringiensis Berliner, which contained a heat-stable-exotoxin, was effectivein controlling larvae of Epilachna varivestis Mulsant in both laboratory and field trials. At a dilution of 10−2, nearly 100% kill was attained in 6 days, and over 60% kill was obtained with a dilution of 10−3. In field tests, a dilution of 5 × 10−2 provided adequate protection to bean plants, resulting in significant increases in plant yield.

This study was designed to determine how the preference of an insect for a plant line is affected by the proximity of less or more attractive lines. The test insects and their host crops were the potato leafhopper, Empoasca fabae (Harris), on potatoes; the imported cabbageworm, Pieris rapae (L.), on cabbage; and the Mexican bean beetle, Epilachna varivestis Mulsant, on lima beans. Comparisons were made between infestations in previously reported resistant and susceptible crop cultivars or lines. Field plots were planted all in a resistant cultivar or line, all in a susceptible cultivar or line, or the two cultivars or lines intermixed. The plant array did not have a significant effect on the size of the Mexican bean beetle population in the resistant or susceptible cultivars. A mixed planting of cultivars preferred and nonpreferred by the imported cabbageworm accentuated the differences between the two cultivars, although an unknown character of the preferred cultivar reduced the differences. Nonpreference was more apparent in isolated pure stands of potato lines than when the preferred and nonpreferred lines were in the same plot.

Insecticides were applied by 3 methods to the root area of the rice plant to control the rice gall midge pachydiplosis oryzac (Wood-Mason). With the 1st method, the seedlings were dipped in systemic insecticides for 5 minutes and transplanted after 12 hours. None of the 4 chemicals tested reduced the infestation. Granular formulations were applied to the fields in the 2nd method. Two applications of several chemicals produced excellent control with the dithiolane iminophosphates and phorate being the most effective up to 98% reduction of the infestation was achieved. One phorate treatment applied 2 weeks after transplanting was superior to 1 or 2 later applications. The 3rd method involved draining the water off the rice field, spraying the soil surface around the plants, and reflooding after 24 hours. This method was used 2 and 4 weeks after transplanting. Carbaryl, phorate, and azinphosmethyl were the most effective, with the carbaryl treatments reducing the infestation by 63%. These tests were conducted in Thailand.

Solanum chacoense is a wild potato species resistant to the Colorado potato beetle,Leptinotarsa decemlineata. Most genotypes ofS. chacoense synthesize the glycoalkaloids solanine (sol) and chaconine (chac) and are hosts of the beetle. A few rare genotypes have a gene(s) for acetylation of carbon-23 of the steroid aglycone of sol and chac. Laboratory bioassays and replicated field tests of clones differing in the presence or absence of the acetyl moiety showed that acetylation of sol and chac markedly affects the response of both adults and larvae to the foliage. Adult feeding deterrency conferred by acetylated forms of sol and chac (leptines) in leaf-disk preference tests was consistent with the degree of antixenosis measured in the field. Development of larvae on foliage of clones with leptines was also inhibited. The studies support the validity of using laboratory bioassays of plants segregating for levels of a suspected defense compound to determine the role the compound has in defending the plant from attack by an insect predator in the field.

Collections of male tobacco horn worms, Manduca sexta (L.), in blacklight (BL) traps can be increased 10 or more times by baiting the traps with virgin female moths (Hoffman et al. 1966, Cantelo and Smith 1971). However. the rearing of these females is expensive and time consuming, and a synthetic female pheromone is not available. Therefore, we hoped to find a substitute material that could be used to increase collections. Isoamyl salicylate was chosen for evaluation because when it was used to bait relatively inefficient screen traps in Tennessee, it caught as many as 925 tobacco hornworms in a season. Also, 16 other species of sphingids were caught, but only Byles lineata (F.) and Xylophanes tersa (L.) were caught “in numbers” (Morgan and Lyon 1928). Moreover, at Oxford, N. C., collections in 12 similar-type traps (Stahl 1954) baited with isoamyl salicylate plus simulated jimson weed flowers averaged 112 M. sexta and 155 tomato hornworms, M. quinquemaculata (Haworth), each year from 1942 through 1953 with peak yearly collections of 414 M. sexta and 218 M. quinquemaculata . (However, in 1949, unbaited BL traps collected 15 × as many hornworm moths (both species) and in 1952–53 7–9× as many as the baited screen traps.)

Blacklight (BL) traps baited with virgin female tobacco hornworms, Manduca sexta (L.), collect appreciably more males than unbaited traps because of the attraction to the pheromone produced by the females (Hoffman et al. 1966). A test is planned in which baited traps will be used in an attempt to suppress populations of hornworms over an entire area. However, a necessary prerequisite for such a test is a container that will hold the female moths at the trap. Also, we wished to keep them alive as long as possible, since they produce the pheromone for at least the 1st 5 days of life (Cantelo and Smith 1971), and we would benefit greatly if they would not have to be replaced often. Ideally, such a container should be designed to permit them to feed and thus live their full life expectancy; however, this moth feeds only while it hovers in flight and, because of its 4-in.-long proboscis, must be substantially above the feeding site. Since it was not practicable to construct and install containers of sufficient size to permit feeding activity at each of the 250 traps that are to be used in the suppression experiment, we designed a cage that would permit them to live as long as possible without feeding.