In vitro rearing of Ooencyrtus nezarae (Hymenoptera: Encyrtidae), an egg parasitoid of Riptortus pedestris (Hemiptera: Alydidae)

Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae) is a polyphagous egg parasitoid of various true bugs, including Riptortus pedestris (Fabricius) (Hemiptera: Alydidae), a major pest of soybean and fruit trees in northeastern Asia. This study was conducted to develop artificial host eggs containing insect haemolymph for mass rearing of O. nezarae. The haemolymph of Chinese oak silkworm (Antheraea pernyi Guérin-Méneville) pupae was found to be most suitable for artificial eggs for the complete development of O. nezarae. Among 764 parasitoid eggs laid in artificial eggs, 49.2% successfully developed to adult parasitoids. The developmental time in artificial eggs was delayed by 3–5 days relative to that observed in natural host eggs; however there was no significant difference in the length of hind tibia between adults that emerged from artificial and natural host eggs. Moreover, new generations that emerged from artificial eggs reproduced on all egg types offered (either natural or artificial eggs). We propose that the artificial eggs developed herein can therefore be an effective means for mass rearing O. nezarae.     

Ovipositional Synergists and Artificial Diets for Trichogramma australicum Girault (Hymenoptera: Trichogrammatidae)

We studied ovipositional synergists and artificial diets for rearing Trichogramma australicum. Artificial "diet A" included 40% haemolymph of Helicoverpa armigera (Hübner) final instar larvae, 30% of a 10% malt solution in deionised water, 20% chicken egg yolk and 10% Neisenheimer's salt solution with 76 units Penicillin and 76 units Streptomycin/ml diet. Artificial "diet B" was identical except Grace's insect medium® replaced Neisenheimer's salt solution. the number of T. australicum larvae in artificial eggs filled with diet A and diet B was not significantly different (P > 0.05). Significantly fewer (P < 0.05) larvae developed to pupae and adults in artificial eggs filled with diet A. Quantity and quality of artificial diet affected the mortality of T. australicum larvae reared in vitro. Ovipositional synergists included 10% gelatine solution, 10% polyvinyl alcohol solution or 1% agar solution in deionised water. Synergist test-solutions were individually smeared on the external surface of artificial eggs (hemispherical depressions in plastic membrane). Eggs laid and number of T. australicum larvae produced were significantly higher in artificial eggs smeared with gelatine than artificial eggs smeared with polyvinyl alcohol, agar or non-smeared (control) eggs.     

Effect of bait formulation and number of traps on detection of navel orangeworm (Lepidoptera: Pyralidae) oviposition using egg traps

Egg traps are the primary tool for monitoring egg deposition of the navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), and for timing treatments for this pest in almonds, Prunus amygdalus Batsch, and pistachios, Pistacia vera L. We compared, in almond and pistachio orchards, the number of eggs per trap in traps baited with almond meal, pistachio meal, or the current standard commercial bait. When considering cumulative eggs captured over an extended period, traps baited with pistachio meal prepared from previous-crop nuts generally captured a similar number of eggs compared with the commercial bait, and more eggs than those baited with almond meal prepared from previous-crop nuts. However, differences in eggs per trap between bait formulations were not as evident when examining individual weeks, particularly in weeks with few eggs per trap, as is typical when treatment decisions are made. The variance in eggs per trap was generally greater than the mean and increased with the mean and, when mean eggs per trap was low, most traps did not have eggs. We discuss implications of these findings for the relative importance of bait type and trap numbers for monitoring, and for experiments comparing egg trap performance.     

Development and reproduction of Geocoris varius (Hemiptera: Geocoridae) on two types of artificial diet

Biological control using the polyphagous predator big-eyed bug Geocoris varius (Uhler) (Hemiptera: Geocoridae) is currently being investigated in Japan. However, the production costs of G. varius are relatively high because the eggs of Ephestia kuehniella Zeller (Lepidoptera; Pyralidae) are used as the major food source for mass rearing. Development time and reproductive fitness were therefore examined for G. varius fed two types of artificial diet based on liver and ground pork. The diets were administered either by wrapping in Parafilm^® or by presenting the food in lyophilized form. The results were compared with those obtained by rearing G. varius on E. kuehniella eggs. Although development time of Geocoris varius fed the artificial diets was significantly delayed compared with G. varius fed on E. kuehniella eggs, delays are slight and not serious for mass rearing projects. The findings suggested that both artificial diets could be used to reduce the costs associated with mass rearing of G. varius.     

Occurrence of the mite Pyemotes sp. (Acari: Pyemotidae) in insect rearing in laboratory

Pyemotidae mites have been reported as ectoparasites of a large number of arthropods, especially of insects. These mites are frequently found attacking insects in different habitats, including insect rearing. This paper reports the occurrence of Pyemotes sp., ventricosus group, in colonies of Tuta absoluta (Meyerick) (Lepidoptera: Gelechiidae), Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) and Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), in the insect rearing laboratory of ESALQ-USP, in Piracicaba, State of S?o Paulo, provoking dematitis in those involved with the rearing. This is the first report of a Pyemotes species parasitizing T. absoluta and S. zeamais. Considering the capacity of Pyemotes to cause dermatitis in human beings, demonstrated by other authors, the direct use of the Pyemotes species found in this work for the control of the reported insect species may not be promising.     

Oil-soluble dyes for marking Spodoptera frugiperda (Lepidoptera: Noctuidae)

Although various biological aspects of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) have been examined, adult movement and dispersal of this insect pest is not well understood. Release-recapture techniques by using marked insects is a useful approach for dispersal studies; however, the marking technique should not significantly affect insect biology or behavior. Therefore, the effect of different concentrations of oil-soluble dyes (Solvent Blue 35 [C.I. 61554], Sudan Red 7B [C.I. 26050], Sudan Black B [26150], Sudan Orange G [C.I. 11920], and Sudan I 103624 [C.I. 12055]) on development, mortality, and fecundity of S. frugiperda was evaluated. Dyes were added to artificial diet used to feed larvae. Larval and pupal development and mortality, adult longevity, and female fecundity were evaluated. High concentrations (400 and 600 ppm) of all dyes led to longer larval and pupal stages. Adult life span and number of eggs were not affected by the dyes. Sudan Red 7B marked both adults and eggs very well. Solvent Blue 35 marked both adults and eggs, but the blue-marked eggs could not be distinguished from some bluish eggs laid by nonlabeled females. Adults and eggs were not adequately marked by the Sudan Black B, Sudan Orange G, and Sudan I 103624 (a yellow dye).     

Comparative Development and Performance of Artificially Reared versus Host-RearedDiapetimorpha introita(Cresson) (Hymenoptera: Ichneumonidae) Wasps

Diapetimorpha introita(Cresson) (Hymenoptera: Ichneumonidae), a native ectoparasitoid ofSpodopteraspp. pupae, was reared in the laboratory on an artificial diet devoid of any insect host components. Diet-reared wasps demonstrated a propensity to search for and parasitize natural hosts in a field cage trial. Longevity of the diet-reared wasps was comparable with the longevity of wasps reared on host pupae. Survival rate ofD. introitawas 61.3% when reared on diet and 76.3% when reared on host pupae. Wasps reared on the artificial diet had longer developmental times, reduced fecundity, and reduced adult weights compared to wasps reared on host pupae. These studies suggest that future research efforts should focus on increasing fecundity and weight of diet-reared wasps and decreasing the mortality and developmental time of wasps reared on the artificial diet. The ability to rearD. introitaon an inexpensive, artificial diet significantly enhances the potential of mass rearing this parasitoid for inundative releases againstSpodopteraspp.     

Influence of predator density,diet and living substrate on developmental fitness of Orius laevigatus

Mass rearing of Orius laevigatus on non‐insect foods could substantially increase the cost‐effectiveness of the production of this biological control agent which is largely based on the use of expensive eggs of the Mediterranean flour moth Ephestia kuehniella. In this study, the effect of substrate quality and predator density on nymphal development of O. laevigatus fed on E. kuehniella eggs, honeybee pollen or an egg yolk based artificial diet was assessed using several types of substrates as shelter materials in the rearing containers (wax paper, bean pod or no extra substrate). In general, E. kuehniella eggs proved to be a nutritionally superior food compared to pollen and artificial diet. Pollen supported nymphal development of O. laevigatus better than the artificial diet. Overall, increasing nymphal density resulted in higher mortality, which may be due in part to cannibalism. The addition of a bean pod compensated for the nutritionally suboptimal artificial, but had a negative effect when O. laevigatus was fed on pollen. The non‐insect foods tested could not adequately replace lepidopteran eggs as a food source for O. laevigatus but they may be useful as an alternative food or in a part of the rearing process.     

Thermal requirements of Galleria mellonella L. (Lepidoptera: Pyralidae) immature stages

The rearing of Galleria mellonella L. in laboratory is important for multiplication of entomopathogenic nematodes, mandatory for biological control studies. The objective of this study was to evaluate the effect of three thermal profiles on development stages of this insect, allowing synchronization of cycle production. Two distinct rearing phases were done: firstly, using nucleous of incubation for development of eggs and, secondly, using circular-aluminum manifolds for development of larvae and pupae. The time necessary for development of the immature stages decreased with higher temperatures. Incubation periods lasted 13.4 days at 22 degrees C, 8.3 at 27 degrees C and 6.8 days at 32 degrees C, while periods for larvae development lasted 40.4, 27.2, and 23.4 days, respectively, for the same temperatures. Development to pupal stage was observed 18.2, 15.0, and 12.2 days, respectively, for the same temperatures. Larval survival was higher at 32 degrees C, however embryonic stages and pupae survival were higher at 27 degrees C. and 22 degrees C, respectively. The threshold temperature was 11.209167 degrees C for the embryonic development stage, 7.695869 degrees C for larval stage, and 1.943050 degrees C for pupal stage of G. mellonella. Thermal constants were 138.380533 DG (degree day) for egg, 554.968830 DG for larvae, and 369.054080 DG for pupae.     

Rearing technique and biological traits of Atheloca subrufella (Hulst) (Lepidoptera: Phycitidae) in coconut fruits

Rearing Technique and Biological Traits of Atheloca subrufella (Hulst) (Lepidoptera: Phycitidae) in Coconut Fruits. Larvae of the coconut moth Atheloca subrufella (Hulst) develop in flowers and fruits of coconut, Cocos nucifera, causing precocious abscission of these structures and, hence, yield decrease. This work studied a feasible and suitable rearing technique for A. subrufella using fruits of coconut. We first determined the appropriate density of larvae to be reared per coconut fruit (among two, three, four or five larvae) and later tested the suitability of this rearing technique for three successive generations. The storage of egg and pupal stages during 0, 5, 10 and 20 days was also studied at 12oC. Based on the fertility life table parameters, the best results were achieved by rearing two or three larvae per fruit as they yielded the best net reproductive rate and intrinsic rate of population increase. In addition, eggs and pupae of A. subrufella can be stored at 12oC up to five days with viability higher than 90%. Adult moths emerged from pupae stored for five days at 12oC produced an average of 219.4 eggs and lived 18.8 days. Storage periods for eggs and pupae over 10 days significantly reduced egg viability and adult fecundity, respectively. Thus, the technique in here described was shown to be suitable for the continuous rearing of A. subrufella in laboratory conditions.     

Platynota rostrana (Walker) (Tortricidae) AND Phidotricha erigens Raganot (Pyralidae): artificial diet effects on biological cycle.

The lepidopterans Platynota rostrana (Walker) (Tortricidae) and Phidotricha erigens Raganot (Pyralidae) have been found frequently in citrus groves in S?o Paulo State in recent years. Since in Brazil, the fertility cycle of these two species is largely unknown, as are details of the damage wrought by them in crops, this research studied these aspects of the two species, which were kept under laboratory conditions (temperature 25 +/- 2 degrees C, 70 +/- 10% RH, 14 h photophase) and on an artificial diet. The duration of the biological cycle (egg-adult) for P. rostrana was 38.3 days and total viability was 44.0%; for P. erigens these values were 32.5 days and 63.6%, respectively. Both species showed five larval instars. Females of P. rostrana laid an average of 308 eggs, whereas those of P. erigens laid an average of 106 eggs. In both species, female pupae were heavier than males. Male and female longevity for both species was nearly 10 days. Based on the data obtained, the artificial diet produced better results in P. rostrana than in P. erigens. If these species, which have the potential to reach pest status in the citrus groves of S?o Paulo State, could be reared on an artificial diet, research on their control by alternative methods would be easier.     

Multispectral imaging for quality control of laboratory‐reared Anastrepha fraterculus (Diptera: Tephritidae) pupae

The sterile insect technique (SIT) has been widely used to suppress several fruit fly species. In southern Brazil, millions of sterile flies of the South American fruit fly, Anastrepha fraterculus Wiedemann (Dipetra: Tephritidae), will be produced in a mass‐rearing facility called MOSCASUL to suppress wild populations from commercial apple orchards. In spite of standard rearing conditions, the quality of pupal batches can be inconsistent due to various factors. The quantification of poor quality material (e.g. empty pupae, dead pupae or larvae) is necessary to track down rearing issues, and pupal samples must be taken randomly and evaluated individually. To speed up the inspection of pupal samples by replacing the manual testing with the mechanized one, this study assessed a multispectral imaging (MSI) system to distinguish the variations in quality of A. fraterculus pupae and to quantify the variations based on reflectance patterns. Image acquisition and analyses were performed by the VideometerLab4 system on 7‐d‐old pupae by using 19 wavelengths ranging from 375 to 970 nm. The image representing the near infrared wavelength of 880 nm clearly distinguished among high‐quality pupae and the other four classes (i.e. low‐quality pupae, empty pupae, dead pupae and larvae). The blind validation test indicated that the MSI system can classify the fruit fly pupae with high accuracy. Therefore, MSI‐based classification of A. fraterculus pupae can be used for future pupal quality assessments of fruit flies in mass‐rearing facilities.     

Development and reproduction of the predatory mite Amblyseius swirskii on artificial diets

Development, survival and reproduction of the predatory mite Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) were assessed when fed on cattail pollen (Typha latifolia L.), dried fruit mite (Carpoglyphus lactis L.), or on two artificial diets. The basic artificial diet (AD1) was composed of honey, sucrose, tryptone, yeast extract, and egg yolk. This diet was enriched (AD2) by adding hemolymph from oak silkworm pupae (Antheraea pernyi (Guérin-Méneville)). Mites fed on C. lactis and AD2 had shorter immature and preoviposition periods than those fed on the other diets. The total number of deposited eggs was significantly higher for females fed on AD2 than for those maintained on the other diets. The intrinsic rate of increase (r_m) of A. swirskii was highest on AD2 and C. lactis, followed by T. latifolia pollen, and AD1. In conclusion, the artificial diet AD2 supported development and reproduction of A. swirskii to the same extent as a factitious prey which is routinely used in the mass rearing of the phytoseiid. Our findings indicate the potential of artificial diets for the mass production of this economically important predatory mite.     

Rearing of Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae) on Artificial Diet

An artificial rearing method was designed for the generalist predator, Chrysopa pallens (Rambur). The rearing media were formulated based on, Orius strigicollis diets for feeding larvae, and two diets for adults were prepared with insect source and non‐insect as their main components. Development of the predators was successfully obtained with the diets for both larval and adult stages. The impact of these diets was recorded for growth during the larval stage and oviposition rates by the females. Total development period and mortality rate of, C. pallens were about 26.9 days and 11%, respectively. The females showed better reproduction with average of 2019 eggs over their life span of 89 days when the artificial diet with non‐insect source was provided. On overall basis the life expectancy and fecundity was better when compared with previous findings.     

Pollen as a source of food for egg parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae)

The value of corn pollen as a food source for Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae) was assessed in the laboratory by testing the effect of different pollen diets on the longevity, capacity of parasitism and other life-table parameters. T. brassicae females that fed on corn pollen and water (wet filter paper dusted with pollen) lived significantly longer (4.97 days) than females that fed on water alone (2.67 days), but significantly shorter than those feeding on honey alone (8.37 days) or corn pollen and honey (8.23 days), respectively, in the absence of host eggs. The presence of European corn borer eggs (Ostrinia nubilalis Huebner, Lepidoptera: Pyralidae) significantly increased longevity. With host eggs available, female T. brassicae that fed on corn pollen and water lived significantly longer (4.9 days) than on water alone (2.60 days), but significantly shorter than on honey alone (12.33 days) or corn pollen and honey (12.17 days), respectively. The cumulative lifetime fecundity was 82.53 offspring pupae when fed on pollen and water, which was significantly higher than 61.70 for water alone but lower than feeding on honey alone (95.70) or corn pollen and honey (99.97), respectively. Compared to water alone, corn pollen and water increased the net reproduction rate (R₀), intrinsic rate of increase (r_m), and finite rate of increase (λ), and reduced the doubling time (T₂), but had no effects on the emergence rate, sex ratio, and mean generation time (T_c). In another set of experiments, 13 out of 30 females reduced the number of pollen grains offered to them. The average number of pollen grains utilized per female in this 48-h test 2.46±0.40 (mean±SE). Hence, T. brassicae used corn pollen as food that significantly increased longevity and fecundity of the tested females. Pollen and honey supplied a complete diet for T. brassicae, compared to pollen and water or water alone.     

A key to larvae and pupae of Sericostoma personatum (Spence) and Notidobia ciliaris (Linné) (Sericostomatidae : Trichoptera) in Britain

SUMMARY. Certain larvae and pupae have been identified as Notidobia ciliaris (Linné) by rearing field-collected larvae to the adult stage and by rearing larvae from eggs laid by a female in captivity. The larvae differ in many important respects from larvae of this species described by earlier workers. Characters are provided to distinguish these larvae and their associated pupae from those of Sericostoma personatum (Spence). The habitat and distribution of both species in Britain is outlined.     

Changes in Biological Characteristics of Trichogramma pretiosum (Hym.: Trichogrammatidae) Reared on Eggs of Anagasta kuehniella (Lep.: Pyralidae) for 23 Generations

Possible changes in biological characteristics of Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae) were monitored during 23 generations reared on eggs of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae), to determine quality control parameters in rearing procedures of this parasitoid. Parasitism rates (percent of eggs parasitized) of T. pretiosum varied from 10 to 76%, with lower values for the first four generations. From the 17th generation, the variability in the parasitism rate was lower. Viability (percent adult emergence rate) of T. pretiosum in eggs of A. kuehniella varied from 22 to 100%, again with lower values in earlier generations. Adult longevity of T. pretiosum varied from 5.3 to 15.9 days, and showed a reduced longevity with increasing number of generations. Sex ratio of the offspring of this parasitoid was not affected by the timing of parasitism on eggs of A. kuehniella.     

A semi-artificial rearing system for the specialist predatory ladybird Cryptolaemus montrouzieri

In the present study a semi-artificial rearing system for the Australian ladybird Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), a specialist predator of mealybugs, was developed. In a first step, a rearing system using eggs of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) as a food and synthetic polyester wadding as an oviposition substrate was compared with a natural rearing system using the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae), as to its effects on the predator’s developmental and reproductive parameters. In a second series of experiments the performance of C. montrouzieri on bee pollen or on a mixture of E. kuehniella eggs and bee pollen was assessed. E. kuehniella eggs proved to be a suitable food to support larval development of the predator. Ladybird larvae reared on flour moth eggs developed two days faster and weighed approximately 10 % more than their counterparts reared on mealybugs. Despite a prolongation of the preoviposition period with ca. eight days and a decrease in egg hatch by about 10 %, C. montrouzieri females fed moth eggs accepted the synthetic wadding as an oviposition substrate and deposited the same number of eggs their counterparts maintained on mealybugs. A mixture of E. kuehniella eggs with pollen yielded similar developmental and reproductive rates as E. kuehniella eggs alone, but a diet of bee pollen alone was not adequate for the predator. Our findings indicate the potential of a rearing system using E. kuehniella eggs as a factitious food and synthetic wadding as an artificial oviposition substrate for the mass production of C. montrouzieri.     

Survival of indianmeal moth and navel orangeworm (Lepidoptera: Pyralidae) at low temperatures

Concerns over insect resistance, regulatory action, and the needs of organic processors have generated renewed interest in developing nonchemical alternative postharvest treatments to fumigants used on dried fruits and nuts. Low-temperature storage has been identified as one alternative for the Indianmeal moth, Plodia interpunctella (Hiibner), and navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), common postharvest pests in California dried fruits and nuts. The response of eggs, nondiapausing larvae, and pupae of both species to exposure to low temperatures (0, 5, and 10 degrees C) was evaluated. Eggs of both species were the least tolerant of low temperatures. At 0 and 5 degrees C, pupae were most tolerant, but at 10 degrees C, nondiapausing larvae of both species were most tolerant, with lethal time (LT)95 values of 127 and 100 d for Indianmeal moth and navel orangeworm, respectively. The response of diapausing Indianmeal moth larvae to subfreezing temperatures also was evaluated. Diapausing larvae were very cold tolerant at -10 degrees C, with LT95 values of 20 and 17 d for long-term laboratory and recently isolated cultures, respectively. Diapausing larvae were far less tolerant at lower temperatures. At -15 degrees C, LT95 values for both cultures were <23 h, and at -20 degrees C, LT95 values were <7 h. Refrigeration temperatures of 0-5 degrees C should be useful in disinfesting product contaminated with nondiapausing insects, with storage times of 3 wk needed for adequate control. Relatively brief storage in commercial freezers, provided that the temperature throughout the product was below -15 degrees C for at least 48 h, also shows potential as a disinfestation treatment, and it is necessary when diapausing Indianmeal moth larvae are present.     

Lethal and sublethal effects of methoxyfenozide on the development, survival and reproduction of the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)

The lethal and sublethal effects of the ecdysone agonist methoxyfenozide on the fall armyworm, Spodoptera frugiperda (J. E. Smith), were investigated by feeding a methoxyfenozide-treated diet to fifth instars until pupation in doses corresponding to the LC10 and LC25 for the compound. Larval mortality reached 8% and 26% in the low and high concentration groups, respectively, on the seventh day of the experiment. A progressive larval mortality of 12% for the LC10 and 60% for the LC25 was observed before pupation. Treated larvae exhibited lower pupal weights, higher pupal mortality, presence of deformed pupae, and more deformed adults than untreated larvae. The incorporation of methoxyfenozide into the diet had a significant effect on the timing of larval development. The development period for males and females was about seven days longer than the controls for both concentrations tested. In contrast, the compound affected neither pupae nor adult longevity. Finally, S. frugiperda adults that resulted from fifth instars treated with methoxyfenozide were not affected in their mean cumulative number of eggs laid per female (fecundity), nor percentages of eggs hatched (fertility), or the sex ratio. Our results suggest that the combination of lethal and sublethal effects of methoxyfenozide may have important implications for the population dynamics of the fall armyworm.