Hot water immersion to ensure quarantine security for Cryptophlebia spp. (Lepidoptera: Tortricidae) in lychee and longan exported from Hawaii.

We determined whether immersion in 49 degrees C water for 20 min, a quarantine treatment developed for disinfestation of fruit flies in lychee, Litchi chinensis Sonn., and longan, Dimocarpus longan (Lourd.) Steud., exported from Hawaii, would also disinfest fruit of two species of Cryptophlebia. The pattern of tolerance to heat in Cryptophlebia illepida (Butler) was generally eggs < neonates < early instars = late instars < pupae. No C. illepida survived immersion for 16 or 20 min. Late fourth and fifth instars were determined to be the most tolerant stage that occurs in harvested fruit. Late instars of Cryptophlebia ombrodelta (Lower) were more tolerant of hot-water immersion than those of C. illepida, but no C. ombrodelta late instars survived immersion for 16 or 20 min. The hot water immersion quarantine treatment for fruit flies should effectively disinfest lychees and longans of any Cryptophlebia.     

DNA diagnostics to identify internal feeders (Lepidoptera: Tortricidae) of pome fruits of quarantine importance

A diagnostic polymerase chain reaction (PCR) method is presented for differentiating among the North American internal apple-feeding pests codling moth, Cydia pomonella (L.); oriental fruit moth, Grapholita molesta (Busck); lesser appleworm, Grapholita prunivora (Walsh); and cherry fruitworm, Grapholita packardi Zeller. An approximately 470-bp fragment of mitochondrial cytochrome oxidase subunit I (COI) was sequenced in three to six specimens of each species. Consistent and diagnostic differences were observed among the species in two regions of COI from which forward and reverse primers were designed to amplify a 112-116-bp segment of the gene. The primer sets were used to selectively amplify DNA from specimens of diverse geographic origin for each corresponding target species. Protocols were adapted for conventional and quantitative PCR, the latter being substantially faster. The method was validated as a decision-making tool for quarantine identifications for Mexico by representatives of their phytosanitary agency (Sanidad Vegetal). The method can facilitate identification of intercepted internal feeding Lepidoptera in apple and pear for many other importing nations.     

Ionizing irradiation quarantine treatment against oriental fruit moth (Lepidoptera: Tortricidae) in ambient and hypoxic atmospheres

Oriental fruit moth, Grapholita molesta (Busck), is a pest of many rosaceous temperate fruits, including pomes, Malus spp., and stone fruits, Prunus spp., in much of the world. However, some areas are free of the pest, and shipments of fruit hosts from infested to noninfested areas may be regulated. Current quarantine treatments for oriental fruit moth include methyl bromide fumigation and cold storage for several weeks. Methyl bromide use is being restricted because it is a stratospheric ozone-depleting substance, and alternatives are sought. Cold is not tolerated by many hosts of oriental fruit moth. The objective of this research was to develop irradiation quarantine treatments against the pest under ambient and hypoxic storage conditions because some hosts of oriental fruit moth are stored in hypoxic atmospheres, and hypoxia is known to lessen the effects of irradiation. In ambient atmospheres, no adults emerged from 58,779 fifth instars (the most radiotolerant stage present in fruit) irradiated with a target dose of 200 Gy (195-232 Gy measured). In atmospheres flushed with nitrogen, 5.3% of adults emerged from 44,050 fifth instars irradiated with a target dose of 200 Gy (194-230 Gy measured), but they died at a faster rate than control adults and without laying eggs. A dose of 232 Gy (the maximum recorded when 200 Gy was targeted) is recommended to disinfest any fruit of oriental fruit moth under ambient and hypoxic atmospheres.     

Toxicity and residual activity of methoxyfenozide and tebufenozide to codling moth (Lepidoptera: Tortricidae) and oriental fruit moth (Lepidoptera: Tortricidae)

A series of studies were conducted to examine the residual activity and toxicity of the ecdysone agonists tebufenozide and methoxyfenozide to codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck), in North Carolina apple systems. Methoxyfenozide exhibited greater activity than tebufenozide against codling moth eggs in dose-response bioassays, with a 4.5- and 5.3-fold lower LC50 value to eggs laid on fruit treated before or after oviposition, respectively. Oriental fruit moth eggs were 57- and 12-fold less sensitive to methoxyfenozide than were codling moth eggs on fruit treated before and after oviposition, respectively. Methoxyfenozide was effective in reducing larval entries of both codling moth and oriental fruit moth in field residual activity bioassays, exhibiting activity for at least 28 d after application. Residue breakdown on fruit was approximately 80% at 28 d after treatment for both methoxyfenozide and tebufenozide, with the most rapid residue decline (60%) occurring during the first 14 d after application. Two applications of methoxyfenozide applied at 14-d intervals provided better canopy coverage and higher residue levels than one application. Spray volume (683 versus 2,057 liters/ha) did not affect the efficacy of methoxyfenozide. Leaf and fruit expansion during the season was measured to determine potential plant-growth dilution effects on residual activity. There was very little increase in leaf area after mid May, but increase in fruit surface area over the season was described by a second order polynomial regression. Implications for codling moth and oriental fruit moth management programs are discussed.     

A practical rearing method for leafrollers (Lepidoptera: Tortricidae)

Abstract

A colony maintenance system is described. This method allowed development of neonate larvae through to the adult stage, to be completed in the container without changing the diet or handling of various stages. It reduced larval inoculation time by c. 85% (as compared with rearing larvae individually). This reduced overall rearing costs.     

Irradiation of adult Epiphyas postvittana (Lepidoptera: Tortricidae): egg sterility in parental and F1 generations

Adult Epiphyas postvittana Walker were irradiated using a Cobalt 60 source to determine the dose needed to achieve complete egg sterility of mated female moths, and egg sterility of female moths mated to F1 generation males. Adult male and female E. postvittana were irradiated at 100, 200, 250, and 300 Gy and their fertility (when crossed with normal moths) was compared with nonirradiated moths. Viable progeny (determined by egg hatch) were found at doses of 100 and 200 Gy, but very little at 250 and 300 Gy. In particular, there was no survival of female progeny into the F1 generation. Males irradiated at 250 and 300 Gy had very low egg eclosion rates (2.25 and 1.86% at 250 and 300 Gy, respectively) when mated with normal females. The F2 generation from those male progeny had a mean percent hatched of < 1.02%. Based on our results, a dose of 250-300 Gy is recommended for irradiation of E. postvittana adults used for sterile insect technique (SIT) if sterility of parental moths is the desired outcome. Our data also suggests that inclusion of F1 hybrid sterility rather than parental generation sterility into programs using the SIT may allow for doses lower than what we have reported, especially during initial phases of an eradication program where increase fitness of moths might be desirable. Further research is needed to verify the use of F1 hybrid sterility in light brown apple moth SIT programs.     

Potential for mating disruption of Sparganothis sulfureana (Lepidoptera: Tortricidae) in cranberries.

The feasibility of disrupting mating of Sparganothis fruitworm with a sprayable microencapsulated formulation of (E)-11-tetradecenyl acetate (E11-14:Ac), the major pheromone component, was evaluated in New Jersey during 1996 and 1997 seasons. In both years, application of encapsulated E11-14:Ac, at 25-187.5 g (AI)/ha, reduced the incidence of mating of virgin females placed in treated plots relative to those placed in control plots. Pheromone trap catches were lower in pheromone treated plots, indicating that fewer male moths were able to locate the traps in treated plots. Larval density and fruit damage were significantly lower in plots treated with 62.5,125, or 187.5 g (AI)/ha of pheromone than in the untreated control. Air and foliage samples were collected to determine the air titers and foliage residuals of E11-14:Ac throughout the adult flight during 1996 and 1997. E11-14:Ac levels in air and foliage samples, declined sharply one wk after the pheromone application. However, detectable levels of E11-14:Ac were present in both air and foliage samples throughout the 3- to 4-wk period after the pheromone application. Multiple applications of pheromone at lower rates may be more effective in maintaining pheromone levels than a single dose at higher rates. These results suggest that mating disruption is a promising strategy to manage Sparganothis fruitworm in cranberries.     

Laboratory rearing of lesser appleworm (Lepidoptera: Tortricidae)

The lesser appleworm, Cydia prunivora (Walsh), was reared successfully in the laboratory. Larvae of various instars were collected in the field from hawthorn fruit, Crataegus spp. Initially, immature apples served as the food source for the larvae in the laboratory. Rearing was conducted in a greenhouse and later in combination with a controlled environment room at 25 degrees C, 50-60% RH, and a photoperiod of 18:6 (L:D) h. Under these conditions, a generation required approximately 30 d. Fifty-six adult lesser appleworm moths emerged from the original field collected hawthorn fruits. After a decline in the number of the F1 generation to 39 moths, the colony on mature apples, increased to in excess of 10,000 moths by the fifth generation with a mean survival rate to adult of 68.0%. When production on immature apples was compared with that on four artificial diets, the most promising of the artificial diets was the lima bean-based diet currently used to rear the oriental fruit moth, Cydia molesta (Busck), with a mean survival rate of 46.4%. The other bean-based diets tested were not as satisfactory. Pear foliage was the preferred oviposition substrate of those tested, including apple and hawthorn foliage. No eggs were deposited on plain waxed paper or glass microscope slides; however, large numbers of eggs were deposited on waxed paper treated with a water extract of pear foliage and immature apples.     

Characterization of a Granulovirus Isolated from Epinotia aporema Wals. (Lepidoptera: Tortricidae) Larvae

A granulovirus (GV) isolated from Epinotia aporema (Lepidoptera: Tortricidae)—a major soybean pest—was studied in terms of its main morphological, biochemical, and biological properties. The ovoidal occlusion bodies were 466 by 296 nm in size, and their most prominent protein had an apparent molecular mass of 29 kDa. Its amino-terminal sequence was remarkably homologous to that of the granulins of other GVs. The DNA genome size was estimated to be 120 kbp. The high specificity and pathogenicity of this newly described granulovirus (EpapGV) indicate that it is indeed a good candidate for the biological control of this pest.     

Characterization of a granulovirus isolated from Epinotia aporema Wals. (Lepidoptera: Tortricidae) larvae

A granulovirus (GV) isolated from Epinotia aporema (Lepidoptera: Tortricidae)-a major soybean pest-was studied in terms of its main morphological, biochemical, and biological properties. The ovoidal occlusion bodies were 466 by 296 nm in size, and their most prominent protein had an apparent molecular mass of 29 kDa. Its amino-terminal sequence was remarkably homologous to that of the granulins of other GVs. The DNA genome size was estimated to be 120 kbp. The high specificity and pathogenicity of this newly described granulovirus (EpapGV) indicate that it is indeed a good candidate for the biological control of this pest.     

Molecular approach to the systematics of European Tortricini (Lepidoptera: Tortricidae)

Tortricini is a cosmopolitan tribe of the subfamily Tortricinae of the lepidopteran family Tortricidae. The most recent systematic of Tortricini are based on the external morphology of imagines and the structure of their genital organs. The present paper is the first comparative molecular study of the representatives of this tribe. We examined DNA variation in a 606 bp fragment of COI mtDNA obtained from 23 species of Tortricini and two representatives of other tribes (Archips podanus of Archipini and Aethes hartmanniana of Cochylini). The position of Spatalistis, Tortrix, Aleimma and Acleris, and some groupings of species within Acleris were confirmed by molecular data, including the synonymization of Croesia and Phylacophora with Acleris. The positions of a few groupings of the Acleris species remain unresolved.     

Developing the sterile insect technique for Cryptophlebia leucotreta (Lepidoptera: Tortricidae): influence of radiation dose and release ratio on fruit damage and population growth in field cages

The effect of radiation dose and different release ratios of treated (T) to untreated (U) Cryptophlebia leucotreta (Meyrick) (Lepidoptera: Tortricidae), on the incidence of fruit damage, the competitiveness of the treated males, and population growth was examined inside field cages. Navel orange trees were individually enclosed in large nylon mesh cages. Newly emerged adult moths treated with either 150 or 200 Gy of gamma radiation were released into the cages at ratios of 5T:1U or 10T:1U. The fruit was collected after 4 wk, and the number of damaged fruit and larval entries per cage were recorded for each treatment. Infested fruit was maintained in the laboratory until all emerging F1 progeny were collected and outcrossed to untreated moths of the opposite sex. Treatment had a significant effect on the mean number of larval entries and on the number of undamaged fruit per cage. The number of larval entries as well as the number of F1 progeny per cage decreased as the overflooding ratio increased. A significant reduction in egg hatch was observed in the progeny of crosses between F1 females or F1 males originating from the treatment cages compared with crosses of F1 moths originating from the control cages. The lowest mean number of fertile F1 adult females and males was obtained from the 150 Gy and 10T:1U ratio treatment. This treatment also showed the lowest per generation rate of increase (< 1 from the parental [P1] to the F1 generation), suggesting that growth in the fertile population would have been prevented if releases of treated moths at this dose and ratio were maintained in the field.     

A chemically defined medium for rearing Epiphyas postvittana (Lepidoptera: Tortricidae)

Abstract

The endemic New Zealand genus Neolimnia is redescribed, and a key is given to the 14 species now included. Four new species are described - Neolimnia raiti, N. pepekeiti, N. ura, and N. repo. Two new synonymies are proposed; N. ocellata Tonnoir &; Malloch with N. castanea (Hutton); and N. dubiosa Tonnoir &; Malloch with N. irrorata Tonnoir &; Malloch. Lectotypes are designated for N. tranquilla (Hutton), N. castanea (Hutton), N. obscura (Hutton), and N. striata (Hutton). Male postabdomens of all species are illustrated. Character variation and generic, subgeneric, and species relationships are discussed briefly.     

Costs of insecticide resistance in Cydia pomonella (Lepidoptera: Tortricidae)

The obvious benefits associated with insecticide resistance for pest species may come at a cost to other life-history traits. In this study, we compared the larval and pupal developmental times, pupal mass wing surface area and wing fluctuating asymmetry (FA) in insecticide resistant and control strains of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), collected from apple (Malus spp.) orchards in central Canada. Resistant strains had significantly longer larval developmental times and lower pupal masses compared with the susceptible strain. Although the forewings of resistant moths were smaller in resistant than control strain, no difference in wing FA was detected. Longer developmental times could increase exposure time to natural enemies, and reduced adult size could affect longevity and total reproductive output.     

Physiological factors regulating polyandry in Lobesia botrana (Lepidoptera: Tortricidae)

Abstract. The effects of several physiological factors related to female multiple mating in the monandrous Lobesia botrana Denis and Schiffermuller (Lepidoptera: Tortricidae) were studied under laboratory conditions. Polyandry was assessed observing the induction of re-calling in previously once-mated females. Female age at first mating had no effect on induction of re-calling during practically the whole of the female lifetime, but in older females it was significantly lower. The percentage of re-calling was negatively correlated with the volume of the spermatophore received, ranging from ≅ 23% with the largest spermatophores to ≅ 75% with the smallest ones. Furthermore, the smaller the spermatophore volume, the earlier the re-calling was induced, significantly reducing die female refractory period after the first mating. Heavy females showed a significantly higher rate of re-calling (52.8%) than light ones (37.0%), but no differences were observed when females received only small spermatophores. This finding was explained by die allometric relationship between me female weight and the size of its reproductive system that affects relative replenishment by the spermatophore. Females with a supply of water displayed a significantly higher rate of re-calling (41.2%) than control females (22.8%), highlighting the effect of adult feeding (or drinking) status on the re-calling behaviour. The short-distance presence of virgin males with once-mated females promoted a re-calling rate (and subsequent matings) close to 37%, significantly higher than that of isolated females (20%). It is concluded mat re-calling and polyandry in L. botrana are controlled, as expected, by a number of mating-derived stimuli, but also to a great extent by other physiological stimuli unrelated to mating. The reproductive strategies in relation to polyandry and the mechanisms controlling female sexual inhibition are discussed.     

A new genus of Grapholitini from Africa related to Thaumatotibia (Lepidoptera,Tortricidae)

Thaumatovalva gen. n. is described and illustrated from the Afrotropical region. As currently defined the genus includes four species: T. deprinsorum sp. n. from the Democratic Republic of Congo; T. albolineana sp. n. (type species) from the Democratic Republic of Congo; T. spinai (Razowski & Trematerra), comb. n., from Ethiopia and Nigeria; and T. limbata (Diakonoff), comb. n., from the Seychelles and Kenya. Thaumatovalva limbata has been reared from the fruit of Cordia somaliensis Baker and C. monoica Roxb. (Boraginaceae) in Kenya. Although structures of the male and female genitalia are extremely similar among three of the four species, male secondary scales on the under surface of the hindwing easily distinguish them.     

Ionizing radiation for quarantine control of Opogona sacchari (Lepidoptera: Tineidae)

A discriminating irradiation dose of 150 gray (Gy) was used to determine the most tolerant immature stages of Opogona sacchari (Bojer) (Lepidoptera: Tineidae). Based on adult emergence, early and late pupae were determined to be the most tolerant stages, and they were significantly more tolerant than eggs, neonate larvae, and larvae that were 1, 2, or 3 wk old. Irradiation treatment of eggs, neonates, 1-wk-old larvae, 2-wk-old larvae, 3-wk-old larvae, early pupae, and late pupae at 150 Gy resulted in a 96, 96, 95, 73, 61, 8, and 9% reduction in adult emergence, respectively. Pupae were treated with irradiation doses between 60 and 400 Gy. Emergence to the adult stage was significantly reduced by irradiation, averaging 90% in experimental controls and 29% in the 400-Gy treatment. Egg production was also reduced by irradiation, although the average age of pupae at the time of irradiation had a larger effect on fecundity. In total, 2,527 pupae treated with 120 Gy eclosed and produced 47,221 eggs and three F1 larvae. In the 150-Gy treatment, 2,927 adults in total emerged from the 4,626 insects treated as pupae. These adults laid 62,878 eggs, none of which hatched. We conclude that a minimum dose of 150 Gy should be sufficient for sterilization of immature O. sacchari infesting export commodities.     

Large-scale, on-site confirmatory, and varietal testing of a methyl bromide quarantine treatment to control codling moth (Lepidoptera: Tortricidae) in nectarines exported to Japan

In total, 30,491 codling moth, Cydia pomonella (L.), 1-d-old eggs on May Grand nectarines in two large-scale tests, and 17,410 eggs on Royal Giant nectarines in four on-site confirmatory tests were controlled with 100% mortality after fumigation with a methyl bromide quarantine treatment (48 g3 for 2 h at > or = 21 degrees C and 50% volume chamber load) on fruit in shipping containers for export to Japan. Ranges (mean +/- SEM) were for percentage sorption 34.7 +/- 6.2 to 46.5 +/- 2.5, and for concentration multiplied by time products 54.3 +/- 0.9 to 74.5 +/- 0.6 g.h/m3 in all tests. In large-scale tests with May Grand nectarines, inorganic bromide residues 48 h after fumigation ranged from 6.8 +/- 0.7 to 6.9 +/- 0.5 ppm, which were below the U.S. Environmental Protection Agency tolerance of 20 ppm; and, organic bromide residues were < 0.01 ppm after 1 d and < 0.001 ppm after 3 d in storage at 0-1 degree C. After completion of larger-scale and on-site confirmatory test requirements, fumigation of 10 nectarine cultivars in shipping containers for export to Japan was approved in 1995. Comparison of LD50s developed for methyl bromide on 1-d-old codling moth eggs on May Grand and Summer Grand nectarines in 1997 versus those developed for nine cultivars in the previous 11 yr showed no significant differences in codling moth response among the cultivars.     

Four newly recorded species of subfamily Olethreutinae (Lepidoptera: Tortricidae) from North Korea

Four species of the subfamily Olethreutinae based on the materials in the Hungarian Natural History Museum are added to the North Korean fauna: Ancylis melanostigma Kuznetsov, Ancylis sativa Liu, Eucoenogenes japonica Kawabe and Eucosma glebana (Snellen). Photographs of adults and genitalia are provided with brief comments on the distribution.