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Simple Summary: Female black soldier flies perch on artificial plants much more often than males, especially early in the day and early in their reproductive lives, times when males are competing with one another in aerial swarms. Artificial perches are implemented by many companies that mass-rear the black soldier fly (BSF), to emulate a natural breeding environment or provide additional surface area for flies to rest; however, basic information about perching behavior is lacking. This experiment tested the effect of adding 0.00, 0.04, 0.26, or 0.34 m2 of surface area to 0.93 m3 cages, each supplied with 90 male and 90 female adults. Female thoraxes marked with acrylic paint, and the number of perching flies of each sex were recorded over 6 d. A time-series analysis revealed the following: (a) females utilized perches 1.42 times more often than males across two trials; (b) especially in the morning where the difference could be as high as 2.56 times as great; (c) this decreased to 0.20–1.57 times more females than males by 1600 h; and (d) this cyclical pattern repeated each day throughout the week with a decreasing female-bias, starting from 2.41-times more females on day 1, which fell to 0.88–1.98-times more females than males on day 6. These dynamics are likely due to the presence of male flies engaging in aerial contests near ultraviolet lamps required for mating, especially during the early hours and early adulthood, aligning with and expanding prior knowledge of black soldier fly mating behavior. [ABSTRACT FROM AUTHOR]

Phytoseiid predatory mites are one of the most important groups of biocontrol agents, commonly used in biological control. The ability to produce these predatory mites economically, at high density on cheap factitious food sources, is a major contributor to their success. Astigmatid mites are the most widely used factitious food for this purpose. In this study, we investigated the potential application of the leaf-dwelling astigmatid mite Czenspinskia transversostriata (Oudemans) (Acari: Winterschmidtiidae) as a prey mite in biological control. We tested whether C. transversostriata is a suitable food source for the predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), both in the laboratory and on cucumber plants. Based on a reproduction trial, C. transversostriata proved to be an equally good food source compared to both pollen of Typha angustifolia L. (Poales: Typhaceae) and a frequently used prey mite Carpoglyphus lactis L. (Acari: Carpoglyphidae). In a pre-establishment trial on cucumber plants, populations of A. swirskii reached equally high densities when supplemented with C. transversostriata, compared to C. lactis. Lastly, we show that C. transversostriata is capable of feeding and reproducing on powdery mildew growing on cucumber plants, thereby slowing down the development of the pathogenic fungus. Results derived from this study show that C. transversostriata may have multiple potential applications in biological control programs. [ABSTRACT FROM AUTHOR]

Understanding the biology and ecology of parasitoids can have direct implications for their evaluation as biological control agents, as well as for the development and implementation of mass-rearing techniques. Nonetheless, our current knowledge of the possible influence of lateralized displays (i.e. the asymmetric expression of cognitive functions) on their reproductive behavior is scarce. Herein, we characterized the behavioral elements involved in courtship, and quantified the durations of 2 important aphid parasitoids, Aphidius ervi Haliday and Aphidius matricariae Haliday (Hymenoptera: Braconidae: Aphidiinae). We quantified the main indicators of copulation and examined the occurrence of lateralized traits at population level. Results indicated that A. matricariae exhibited longer durations of wing fanning, antennal tapping, pre-copula and copula phases compared to A. ervi. Postcopulatory behavior was observed only in A. matricariae. Unlike other parasitoid species, the duration of wing fanning, chasing, and antennal tapping did not affect the success of the mating of male A. ervi and A. matricariae. Both species exhibited a right-biased female kicking behavior at the population level during the pre-copula. Our study provides insights into the fundamental biology of aphidiine parasitoids and reports the presence of population-level lateralized mating displays, which can serve as useful benchmarks to evaluate the quality of mass-rearing systems. [ABSTRACT FROM AUTHOR]

Orius laevigatus (Fieber 1860) (Hemiptera: Anthocoridae) is a commercially used predator against soft-bodied pests in greenhouses. Many researchers have done studies on oviposition preference and hatching rate of O. laevigatus which are essential components for the mass-rearing studies of biocontrol agents. In addition, the effects of succulent plants and their potential to use for mass-rearing of O. laevigatus have not fully examined. This study has been done to determine the most suitable host plant for the oviposition preference of O. laevigatus at laboratory conditons between the year 2021 and 2022. No-choice and choice experiments were conducted for the five different succulent plants (Sedum nussbaumerianum Bitter, Kalanchoe daigremontiana Raym.-Hamet & H.Perrier, Kalanchoe blossfeldiana Poelln. (Saxifragales: Crassulaceae), Senecio barbertonicus Klatt. (Asterales: Asteraceae) and Aptenia cordifolia (L.f.) N.E.Br. (Caryophyllales: Aizoaceae) at 25ºC ± 2. %65 ± 10 relative humidity, and 16:8 L: D in climate rooms; According to the results of the No-choice experiment, Kalonchoe blossfeldiana, A. cordifolia, and S. barbertonicus were found the most successful host plant in terms of daily (5.14 ± 0.33, 6.73 ± 0.43, 6.19 ± 0.43) and total laid eggs (74.24 ± 5.70, 61.64 ± 4.51, 84.67 ± 5.50) and hatching ratio (75.01 ± 3.45, 74.40 ± 2.06, 64.26 ± 3.00). Out of these three host plants used for the choice experiment, Kalonchoe blossfeldiana was determined as the most suitable host plant in terms of daily and total laid eggs (3.42 ± 0.38, 33.28 ± 3.98), and hatching rate (22 72.40 ± 2.80 per cent). Consequently, K. blossfeldiana was found to be the most suitable host plant in terms of oviposition and hatching performance for the mas-rearing of O. laevigatus. [ABSTRACT FROM AUTHOR]

Abstract Background Crop residues and agro-industrial by-products constitute an enormous pool of unused and often neglected resources that could be productively utilized for rearing edible insects to meet the global demand for animal-based protein. Utilizing such products as feedstocks can lower the cost of edible insect production and reduce associated environmental pollution. Methods We evaluated the biology (survival, developmental duration, and adult fresh weight) of Ruspolia differens reared on eleven locally available agricultural by-products in Uganda, namely; dry maize cob, waste from a locally brewed finger millet drink, cotton seed cake, soybean hull meal, sunflower cake, pumpkin pulp, peelings of unripe banana, cassava, sweet potato, pineapple and pumpkin. Germinated finger millet was used as a control. Newly hatched (1 day old) nymphs were reared individually on each diet until 14 days post adult emergence. The nutritional profiles of the by-products were also determined. General linear models were fitted to analyse whether R. differens performance differed between sexes and among diets. The relationship between R. differens performance and the nutritional profiles of the diets were tested by Pearson correlation coefficient. Results Only three test diets (soybean hull meal, dry maize cob, and the local brew waste) supported survival till the adult stage. Nymphal survival negatively correlated with diets’ crude fibre content (r = − 0.96, p = 0.042). Nymphal development duration significantly differed among the diets, with the shortest duration under soybean hull meal (approx. 138 days) and the longest under the local brew waste (205 days). Nymphal development duration positively correlated with diets’ crude fibre content (r = 0.95, p = 0.022). Adult fresh weight at emergence and 14 days post emergence did not differ across the test diets. Female individuals were ~ 1.3 times heavier than males 14 days post emergence, although both sexes had similar weights at adult emergence. The levels of secondary metabolites in the diets were not associated with any growth performance parameters of R. differens. Conclusions Our findings suggest that R. differens can thrive and develop on some agricultural by-products. The results could guide the design of R. differens mass-rearing programs using locally available agricultural by-products.

Artificial perches are implemented by many companies that mass-rear the black soldier fly (BSF), to emulate a natural breeding environment or provide additional surface area for flies to rest; however, basic information about perching behavior is lacking. This experiment tested the effect of adding 0.00, 0.04, 0.26, or 0.34 m2 of surface area to 0.93 m3 cages, each supplied with 90 male and 90 female adults. Female thoraxes marked with acrylic paint, and the number of perching flies of each sex were recorded over 6 d. A time-series analysis revealed the following: (a) females utilized perches 1.42 times more often than males across two trials; (b) especially in the morning where the difference could be as high as 2.56 times as great; (c) this decreased to 0.20–1.57 times more females than males by 1600 h; and (d) this cyclical pattern repeated each day throughout the week with a decreasing female-bias, starting from 2.41-times more females on day 1, which fell to 0.88–1.98-times more females than males on day 6. These dynamics are likely due to the presence of male flies engaging in aerial contests near ultraviolet lamps required for mating, especially during the early hours and early adulthood, aligning with and expanding prior knowledge of black soldier fly mating behavior.

The rearing of fall armyworm, Spodoptera frugiperda larvae in cohorts is usually associated with high levels of cannibalism-induced mortalities especially in the later instar larvae. To avoid this problem, rearing is done using an individual-based method that often requires relatively more man-hours, man power and laboratory space. To substantially reduce cannibalism-induced mortalities in cohort-based laboratory cultures of S. frugiperda, the primary factors influencing intra-instar cannibalism must be properly elucidated. In this study, the effect of food quantity, number of larvae reared (larval population density) and size of rearing container on cannibalism-induced mortalities was investigated at the fifth, early sixth and late sixth (fully mature) instar stages of S. frugiperda. Results showed that at each instar stage, larval population density rather than food quantity, significantly (p < 0.0001) influenced cannibalism-induced mortalities. In addition, no significant interactions (p > 0.11) were observed between both factors. At the late sixth instar, the highest cannibalism-induced mortality (74.67%) occurred when 15-larvae fed only two grams of food were reared together. However, when food quantity increased to five grams, observed mortality was 52.00%. While higher mortalities were generally observed in small rearing containers, the size of larval-rearing container was not a significant (p = 0.01) factor influencing cannibalism-induced mortalities at the three instar stages. The foregoing suggests that while food quantity may not be the most important factor influencing intra-instar cannibalism in S. frugiperda, it nonetheless plays a synergistic role with the number of larvae being reared, and is more important than the size of rearing container. [ABSTRACT FROM AUTHOR]

Larval diet is one of the key factors in establishing a mass-rearing/production system for Wolbachia-based approaches that promotes high-quality and high-performance adult mosquitoes at a low/reasonable cost. To identify a suitable larval diet for Aedes aegypti infected with the Wolbachia line (wMID) and wild-type lab-established line (MID), four diets with different protein sources (ranging from 42 to 75%) were compared: fish food (TIL), bovine liver powder (COW), porcine powder meal (PIG), and a mix standard laboratory diet (MFOOD). The COW diet for wMID and MID (without affecting survival to the pupal stage) showed a shorter time to pupation, and the average time was 6 to 7 days, respectively. No significant differences were observed on pupation for wMID and MID, which ranged between 92 and 95% and 96–98%, respectively. A larger pupae size was observed among the TIL, COW, and MFOOD diets for wMID; no differences were recorded for MID. With the COW diet, wMID (7.90 ± 0.06) and MID (7.76 ± 0.10) males had shorter development times from LI to emergence. The stability of the Wolbachia infection was not affected by the diets evaluated. Independently of the Wolbachia infection, all diets are suitable for mass-production and maintenance of Ae. aegypti. Overall, no negative impact was observed on the life history traits evaluated. Considering these results, along with the relative costs of the four diets, PIG and TIL are viable choices given their affordability, accessibility of ingredients in the area. These two low-cost and suitable diets could be used for the Ae. aegypti mass-rearing system in Mexico. [ABSTRACT FROM AUTHOR]

Abstract Background Telenomus remus Nixon is an important egg parasitoid of Spodoptera spp. pests and, as such, has potential as a biological control agent. Spodoptera litura (Fabricius) is a significant pest of many economically important crops worldwide. This study was conducted to evaluate the demographic parameters and functional response of T. remus on the S. litura eggs. Results T. remus can lay 186.90 eggs/female in the lifetime, adult preoviposition period was 0 days, total preoviposition period was 10.03 days, and the ratio of female and male offspring was 0.495 and 0.421, respectively. In addition, most females emerged from 24 h-old eggs, whereas most males emerged from 48 h-old eggs. The intrinsic rate of increase, finite rate of increase, net reproductive rate, mean generation time, and population doubling time were 0.3506 d–1 1.4199 d–1 92.45 offspring/individua, 12.91 days and 1.98 days, respectively. The net killing rate of T. remus on S. litura was 101.49 eggs/female, indicating the high capacity of T. remus to parasitize S. litura eggs. Moreover, the higher the egg density, the higher the parasitism rate by female T. remus, although there was a trend of parasitism stabilization at an egg density of 100, indicating a type II functional response curve for this parasitoid. Conclusion Overall, these findings suggest that T. remus can be efficiently reared on S. litura eggs and shows potential as biocontrol agent for this economically important pest species.

The invasive tree Tecoma stans (L.) Juss. ex Kunth var stans (Bignoniaceae) has been targeted for biological control in South Africa since 2003. Plant nutrients contained in fertilizers typically improve host-plant quality, thereby enhancing the fitness of insect herbivores deployed as weed biocontrol agents. We investigated the effect of increasing nutrient levels (fertilizer treatments) on the growth of potted T. stans plants and on the subsequent performance of the root-feeding beetle Heikertingerella sp. (Chrysomelidae). Enhanced performance of Heikertingerella sp. in culture will improve mass-rearing initiatives for releases in South Africa. Ten newly emerged mating pairs of Heikertingerella sp. were exposed under glasshouse conditions to caged plants that were treated with four regimes of nitrogen: phosphorus: potassium 2:3:2 (14%) + carbon (8%) fertilizer, namely zero (control), low (5.6 g/m2), medium (9.4 g/m2) and high (13.2 g/m2). Increasing nutrient levels significantly increased leaf production and above – and below-ground biomass accumulation in T. stans plants. Similarly, the performance of Heikertingerella sp. was improved substantially, with significantly and progressively higher levels of P1 adult feeding and F1 progeny production, and significantly and progressively reduced F1 developmental times, under increasing nutrient levels. While F1 adult size was significantly increased by fertilizer application relative to the controls, there were no significant differences between the three nutrient levels. Although the high fertilizer application rates were the most suitable for the culturing and mass-rearing of Heikertingerella sp. adults, medium fertilizer applications may prove more economical to improve host-plant quality and boost beetle numbers for release. [ABSTRACT FROM AUTHOR]

Abstract Background Aphidophagous syrphid, Ischiodon scutellaris (Fabricius) (Diptera: Syrphidae) is an effective predator of aphids that infest many agricultural and horticultural crops. Cowpea aphid, Aphis craccivora Koch (Hemiptera: Aphididae), is the natural host for culturing syrphid predator, I. scutellaris. The present study was conducted to evaluate the feeding and development of I. scutellaris on seven species of aphid hosts viz., A. craccivora, Aphis fabae Scopoli, Aphis gossypii Glover (from cotton), Schoutedenia emblica (Patel & Kulkarni), Brevicoryne brassicae (L.), Aphis gossypii (from okra) and Hyperomyzus carduellinus (Theobald) and to identify an alternative aphid host to maintain the culture of I. scutellaris during the situation of non-availability/loss of the culture of A. craccivora. Results Aphis fabae was not accepted for feeding by the larvae of I. scutellaris. The larvae of I. scutellaris did not survive on S. emblica. The descending order of feeding potential of aphids by I. scutellaris was A. craccivora > H. carduellinus > B.brassicae > A. gossypii (from cotton) > A. gossypii (from okra) > S. emblica. The larva of I. suctellaris completed its development in combination of the aphid prey (A. craccivora + H. carduellinus). The net reproductive rates (R 0) of I. scutellaris when fed on A. craccivora and H. carduellinus were 308.28 and 302.33, respectively. The intrinsic rate of increase (r) of I. scutellaris was significantly higher when reared on H. carduellinus (0.155 ± 0.003) than on A. craccivora (0.143 ± 0.004). Conclusion The results confirmed that H. carduellinus reared on Lactuca virosa could serve as an alternate host for the mass production of I. scutellaris.

Background: The coconut black-headed caterpillar, Opisina arenosella Walker (Lepidoptera: Xyloryctidae) has been a serious defoliator of coconut plants in many coconut producing countries including Vietnam. Trichospilus pupivorus Ferrière (Hymenoptera: Eulophidae) is pupal endo-parasitoid of O. arenosella with high percent parasitism and abundance in the coconut fields and appears to be a good biological control agent against the coconut black-headed caterpillar in Vietnam. The objective of this study was to investigate the developmental biology of T. pupivorus on O. arenosella. Methods: The experiment was carried out at the Faculty of Agronomy, Nong Lam University, Viet Nam during 2020 and 2021. The developmental biology of T. pupivorus on O. arenosella was studied in the laboratory at a constant temperature of 28°C and a photoperiod of 12L: 8D. Result: Total developmental time from egg to adult emergence was 14.0 days. The females laid a mean of 124.2 eggs during an average lifespan of 9.4 days. The number of progenies emergence from a single pupa of O. arenosella was 103.8. The offspring sex ratio was female-biased (8.0%). The results would contribute to the knowledge of the biology of this parasitoid to optimize a mass rearing system for a biological control program against O. arenosella. [ABSTRACT FROM AUTHOR]

Mass-rearing procedures of insect species, often used in biological control and Sterile Insect Technique, can reduce the insects competitiveness in foraging, dispersal, and mating. The evocation of certain behaviours responsible to induce specific neuroendocrine products may restore or improve the competitiveness of mass-reared individuals. Herein, we used a mass-reared strain of Ceratitis capitata as model organism. C. capitata is a polyphagous pest exhibiting territorial displays that are closely related to its reproductive performance. We tested if the behaviour of C. capitata males could be altered by hybrid aggressive interactions with a conspecific-mimicking robotic fly, leading to more competitive individuals in subsequent mating events. Aggressive interactions with the robotic fly had a notable effect on subsequent courtship and mating sequences of males that performed longer courtship displays compared to naïve individuals. Furthermore, previous interactions with the robotic fly produced a higher mating success of males. Reproductive performances of C. capitata males may be improved by specific octopaminergic neurones activated during previous aggressive interactions with the robotic fly. This study adds fundamental knowledge on the potential role of specific neuro-behavioural processes in the ecology of tephritid species and paves the way to innovative biotechnological control methods based on robotics and bionics. [ABSTRACT FROM AUTHOR]

Background: Aphidophagous syrphid, Ischiodon scutellaris (Fabricius) (Diptera: Syrphidae) is an effective predator of aphids that infest many agricultural and horticultural crops. Cowpea aphid, Aphis craccivora Koch (Hemiptera: Aphididae), is the natural host for culturing syrphid predator, I. scutellaris. The present study was conducted to evaluate the feeding and development of I. scutellaris on seven species of aphid hosts viz., A. craccivora, Aphis fabae Scopoli, Aphis gossypii Glover (from cotton), Schoutedenia emblica (Patel & Kulkarni), Brevicoryne brassicae (L.), Aphis gossypii (from okra) and Hyperomyzus carduellinus (Theobald) and to identify an alternative aphid host to maintain the culture of I. scutellaris during the situation of non-availability/loss of the culture of A. craccivora. Results: Aphis fabae was not accepted for feeding by the larvae of I. scutellaris. The larvae of I. scutellaris did not survive on S. emblica. The descending order of feeding potential of aphids by I. scutellaris was A. craccivora > H. carduellinus > B.brassicae > A. gossypii (from cotton) > A. gossypii (from okra) > S. emblica. The larva of I. suctellaris completed its development in combination of the aphid prey (A. craccivora + H. carduellinus). The net reproductive rates (R0) of I. scutellaris when fed on A. craccivora and H. carduellinus were 308.28 and 302.33, respectively. The intrinsic rate of increase (r) of I. scutellaris was significantly higher when reared on H. carduellinus (0.155 ± 0.003) than on A. craccivora (0.143 ± 0.004). Conclusion: The results confirmed that H. carduellinus reared on Lactuca virosa could serve as an alternate host for the mass production of I. scutellaris. [ABSTRACT FROM AUTHOR]

Age influences host-plant quality, which is a key determinant of the fitness of herbivorous insects and hence biological control agents of invasive plants. We assessed the effect of host-plant age on the performance of the root-feeding flea beetle Heikertingerella sp. (Coleoptera: Chrysomelidae: Galerucinae), which was recently approved for release against the invasive tree Tecoma stans (L.) Juss ex Kunth var. stans (Bignoniaceae) in South Africa. Using similar-sized plants that were aged from one to three years, our aim was to determine an optimal host-plant age to facilitate mass-rearing of the beetle for impending releases. While significantly more F1 progeny were produced with increasing plant age, presumably due to larger root masses in progressively older plants, plant age did not influence the size of the F1 adults. There was no significant effect of plant age on the survival and percentage of leaves damaged by the P1 adults. Tecoma stans plants of all ages produced significantly fewer leaves when exposed to feeding by Heikertingerella sp. adults and their larval progeny, relative to the unexposed control plants. Irrespective of plant age, adults displayed higher feeding intensity on the younger leaves at the top sections of the plants than on the older leaves on the middle and bottom sections. Although plants of all three ages were suitable for adult feeding and survival in quarantine cultures, progressively older plants are best suited for F1 progeny production and therefore for the mass-rearing of Heikertingerella sp. for releases. [ABSTRACT FROM AUTHOR]

The melon fly, Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae), is a pest of many important cucurbit crops. The sterile insect technique (SIT) has been used to control the species and involves the release of mass-reared, sterile males to obtain matings with wild females. The ability of released males to compete successfully against wild males is key to the success of the SIT. Artificial selection acting under mass-rearing conditions may alter male behavior in ways that decrease acceptance by wild females. A pupal-color sexing strain of melon fly (termed T1) was developed in Hawaii, and males of this strain appear equal to wild males in mating competition. In the present study, trials conducted in both laboratory and field cages showed that T1 and wild females mate indiscriminately among T1 and wild males. Trials conducted in field cages also assessed the impact of two elements—overflooding ratio (i.e., ratio of mass-reared to wild males) and use of male-only vs. bisexual releases—on the mating success of T1 males. Observations of individual male–female pairs further revealed that the incidence of male mounting and the proportion of successful mounts (i.e., copulations) were independent of the strain identities of the paired flies. [ABSTRACT FROM AUTHOR]

With the potential to process the world's agricultural and food waste, provide sustainable fodder for livestock, aquaculture, and pet animals, as well as act as a source of novel biomolecules, the black soldier fly, Hermetia illucens, has been launched into the leading position within the insects as feed industry. Fulfilment of these goals, however, requires mass‐rearing facilities to have a steady supply of neonate larvae, which in‐turn requires an efficient mating process to yield fertile eggs; yet, little is known about adult reproductive behavior, nor what physiological factors lead to its emergence. Moreover, fertile egg production tends to be highly variable in colony. Therefore, this review brings together what is currently known of the organismal biology of H. illucens, compiling information on adult morphology, physiology, biogeography, genomics, and behavioral ecology. As a holistic synthesis, it highlights several directions of interest for research to follow. [ABSTRACT FROM AUTHOR]

The coconut black-headed caterpillar, Opisina arenosella Walker (Lepidoptera: Xyloryctidae) has been one of the most serious defoliators of coconut plants in Vietnam. Brachymeria kamijoi Habu (Hymenoptera: Chalcididae) is a pupal parasitoid of O. arenosella with high percent parasitism and abundance in the coconut fields and appears to be a good biological control agent against the coconut black-headed caterpillar in Vietnam. This study was carried out at Entomology Laboratory, Faculty of Agronomy, Nong Lam University, Vietnam during 2020 - 2021 to determine some biological characteristics of B. kamijoi on O. arenosella at a constant temperature of 28 °C and a photoperiod of 12L: 8D. Total developmental time from egg to adult emergence was 13.8 days. The females laid a mean of 98.1 eggs during an average lifespan of 30.7 days. Fecundity peaked at a large range of age 7-29 days. The results would contribute to the knowledge of the biology of B. kamijoi to optimize a mass-rearing system for a biological control programme against O. arenosella. [ABSTRACT FROM AUTHOR]

Integrated Pest Management (IPM) is a pest control approach that considers all available strategies and their subsequent integration for pest control. The Biological Control (BC) of pests through the use of natural enemies is an outstanding strategy. Biological control by generalist predators has had a highlighted relevance in the last decade. This strategy by augmentation demands mass rearing of these organisms. In the Neotropical Region Chrysoperla externa (Neuroptera: Chrysopidae) is of great importance for its high voracity and its wide range of hosts. The aim of this study was to describe the external changes of the eggs, especially in colour and shape, associated with the intrachorionic development of C. externa embryos, to characterize them morpho-colorimetrically. A practical key from its embryonic development determination was constructed as a tool for mass rearing technique, providing valuable information that could facilitate BC implementation for IPM programs in developing regions. [ABSTRACT FROM AUTHOR]

Body size is one of the most determining traits in the fitness of insects. For fruit fly (Diptera: Tephritidae) control programs using sterile insect technique, size is a valuable indicator of the quality of the mass-reared insects. However, laboratory colonization and mass-rearing conditions can contribute to the disparity in phenotypic traits between laboratory and wild populations, reducing the performance of sterile males and the effectiveness of the sterile insect technique. Hence the relevance of evaluating the possible variations in body size (size and shape) in 2 economically important species: Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart) (both Diptera: Tephritidae). In this study, we compared pupal size distribution of wild and laboratory populations, using 3 parameters: pupal length, width, and weight. Additionally, we recorded the sex of the emerged adults to determine the sexual dimorphism related to pupae size. In A. ludens, male and female wild pupae were longer than pupae of their laboratory congeners, while laboratory pupae were wider and heavier than the wild pupae. In A. obliqua, male and female wild pupae were significantly larger than pupae of their laboratory congeners in all size parameters. We confirmed the sexual dimorphism in pupal size in both species and both populations. Females were bigger than males in all pupal size parameters. This study provides useful information about size distributions and dimorphism from pupal size, providing baseline data with potential implications and applications in mass rearing of A. ludens and A. obliqua for the application of the sterile insect technique. El tamaño corporal es uno de los rasgos más determinantes en la aptitud de los insectos. Para los programas de control de moscas de la fruta (Diptera: Tephritidae) que utilizan la técnica del insecto estéril, el tamaño es un indicador valioso de la calidad de los insectos de cría masiva. Sin embargo, la colonización en laboratorio y las condiciones de cría masiva pueden contribuir a la disparidad en los rasgos fenotípicos entre las poblaciones silvestres y de laboratorio, reduciendo el desempeño de los machos estériles y la efectividad de la técnica del insecto estéril. De aquí la relevancia de evaluar las posibles variaciones en el tamaño corporal (tamaño y forma) en dos especies económicamente importantes: Anastrepha ludens (Loew) y Anastrepha obliqua (Macquart). En este estudio, comparamos la distribución del tamaño de pupas de una población silvestre y de laboratorio, utilizando 3 parámetros: longitud, ancho y peso de pupas. Además, registramos el sexo de los adultos emergidos para determinar el dimorfismo sexual relacionado con el tamaño de la pupa. En A. ludens, las pupas de machos y hembras silvestres fueron más largas que las pupas de sus congéneres de laboratorio, mientras que las pupas de laboratorio fueron más anchas y pesadas que las pupas silvestres. En A. obliqua, las pupas de machos y hembras silvestres fueron significativamente más grandes que las pupas de sus congéneres de laboratorio en todos los parámetros de tamaño. Confirmamos el dimorfismo sexual en el tamaño de las pupas en ambas especies y en ambas poblaciones. Las hembras fueron más grandes que los machos en todos los parámetros de tamaño de pupa. Este estudio proporciona información útil acerca de las distribuciones del tamaño y el dimorfismo del tamaño de la pupa proporcionando datos de referencia con potenciales implicaciones y aplicaciones en la cría masiva de A. ludens y A. obliqua para la aplicación de la técnica del insecto estéril. [ABSTRACT FROM AUTHOR]

Aims: A wide range of vector control programmes rely on the efficient production and release of male mosquito. Asaia bacteria are described as potential symbionts of several mosquito species but their relationship with Aedes aegypti has never been rigorously tested. Here, we aimed to quantify the benefits of three Asaia species on host development in Ae. aegypti, and the ability of these bacteria to form a stable symbiotic association with growing larvae., Methods and Results: In order to disentangle direct and indirect effects of Asaia inoculation on host development, experiments used insects with an intact microbiome and those reared in near-aseptic conditions, while we characterized bacterial communities and Asaia densities with culture dependent and independent methods (16S rRNA amplicon sequencing). Neonate larvae were inoculated with Asaia spp. for 24 h, or left as uninoculated controls, all were reared on sterile food. Aseptic larvae were produced by surface sterilization of eggs. Although all Asaia were transient members of the gut community, two species accelerated larval development relative to controls. The two mutualistic species had lasting impacts on the larval microbiome, largely by altering the relative abundance of dominant bacteria, namely Klebsiella and Pseudomonas. Axenic larvae were dominated by Asaia when inoculated with this species but showed slower development than conventionally reared insects, indicating that Asaia alone could not restore normal development., Conclusions: Our results reveal Asaia as a poor mutualist for Ae. aegypti, but with a species-specific positive effect on improving host performance mediated by interactions with other bacteria., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Successful implementation of the sterile insect technique (SIT) against Aedes aegypti and Aedes albopictus relies on maintaining a consistent release of high-quality sterile males. Affordable, rapid, practical quality control tools based on the male’s flight ability (ability to escape from a flight device) may contribute to meeting this requirement. Therefore, this study aims to standardize the use of the original FAO/IAEA rapid quality control flight test device (FTD) (version 1.0), while improving handling conditions and reducing the device’s overall cost by assessing factors that could impact the subsequent flight ability of Aedes mosquitoes. The new FTD (version 1.1) is easier to use. The most important factors affecting escape rates were found to be tube color (or “shade”), the combined use of a lure and fan, mosquito species, and mosquito age and density (25; 50; 75; 100 males). Other factors measured but found to be less important were the duration of the test (30, 60, 90, 120 min), fan speed (normal 3000 rpm vs. high 6000 rpm), and mosquito strain origin. In addition, a cheaper version of the FTD (version 2.0) that holds eight individual tubes instead of 40 was designed and successfully validated against the new FTD (version 1.1). It was sensitive enough to distinguish between the effects of cold stress and high irradiation dose. Therefore, the eight-tube FTD may be used to assess Aedes’ flight ability. This study demonstrated that the new designs (versions 1.1 and 2.0) of the FTD could be used for standard routine quality assessments of Aedes mosquitoes required for an SIT and other male release-based programs.

• Bridging the research-implementation gap requires engagement with affected communities. • Implementing biological control in a system with a history of chemical and mechanical control can be challenging. • Augmentative biological control was implemented on a nutrient-enriched impoundment by fostering a community of practice. • Nearly half a million biological control agents were released between 2018 and 2023 through the collective efforts of professional and private stakeholders. • Bridging the boundaries between the research and public sector has strengthened biological control efforts, enabling successful and sustainable management of water hyacinth on Hartbeespoort Dam. Water hyacinth has been present on Hartbeespoort Dam since the 1960s. Historical weed management consisted of herbicide and mechanical/manual removal. However, due to funding constraints, biological control was implemented as a cost-effective and environmentally friendly alternative. The impoundment receives excessive phosphorus and nitrogen due to its location downstream from densely populated cities, which includes one of the capital cities of South Africa, Pretoria. Considering that Hartbeespoort Dam is in a temperate region, with cool winters, we embarked on an augmentative biological control approach. To increase our biological control efforts, we had to bridge the research-implementation gap. We fostered a community of practice, by creating a space for the affected community to actively participate in the programme. This would give us the opportunity to share scientific knowledge to affected stakeholders, gauge the public perception, and align potential goals. Social media, in-person meetings and training sessions were used to engage with the public. To increase the availability of the water hyacinth biological control agent, Megamelus scutellaris , community members (i.e. private stakeholders) were offered the opportunity to manage satellite rearing stations. Between 2018 and 2023, nearly half a million Megamelus scutellaris individuals, sourced from both the Centre for Biological Control's mass-rearing facility and satellite rearing stations around Hartbeespoort Dam, have been released into the dam. Water hyacinth cover on the dam drastically declined every year following a build-up of Megamelus scutellaris. Over the course of the programme, private stakeholders that were actively involved grew from two (2018) to 16 (2023). Analysing the participation of private stakeholders using a framework that looks at the level of value gained from our interactions, two partners reached a value chain phase that led to an expansion of biological control implementation. Longer-term private stakeholders generated increased interest for biological control implementation in their community, which resulted in recruitment of new private stakeholders. We also evaluated the knowledge of the affected community in 2023 through an online questionnaire. Out of 132 respondents, 51 % had knowledge of what biological control entails, with 56 % acknowledging that biological control has had a positive impact on the management of water hyacinth. Bridging the research-implementation boundary has strengthened biological control efforts, enabling a more sustainable approach to the management of water hyacinth on Hartbeespoort Dam. However, continued community engagement is necessary to increase the public's knowledge about the practice of biological control. [ABSTRACT FROM AUTHOR]

The mealworm Tenebrio molitor (Coleoptera: Tenebrionidae) is the most consumed insect in the world. This study aims to optimize the space in the mass-rearing facilities of this insect, as well as to evaluate the effect of photoperiod on the reproduction and growth of the larvae. The two cross-over factors studied were photoperiods regimes (8L:16D and 0L:24D) and four density treatments (0.25; 0.75; 1; 1.5 ind/cm2) under rearing conditions of 28 ± 1 °C and 70 ± 5%relative humidity. Statistical analysis showed that density and photoperiod (P > 0.05) had no effect on pupal development. Moreover, population density and photoperiod had no effect on pupal development and adult survival. However, average fertility was affected by population density and the optimal population density was 0.25 adults/cm2.Photoperiod had no effect on the fertility of T. molitor. Regarding total fecundity, there is no interaction between the two factors. The fecundity of T. molitor was significantly affected by population density. The highest fecundity was obtained at 1.5 adult/cm2. The optimal combination of photoperiod and density for larval development was of 0.25 ind/cm2 with 8 h of light per day. The conversion rate was not affected by the factors studied. These findings enable to optimize the mass-rearing of T. molitor and reduce the cost and environmental impact of these facilities. [ABSTRACT FROM AUTHOR]

Simple Summary: In insects, it is known that the diet during the larval stage affects traits in the adult stage. However, it is still unclear how it affects reproductive traits such as ejaculation. The ejaculate contains many proteins and therefore requires much nutrition, so the larval diet strongly influences it. Males of the West Indian sweet potato weevil Euscepes postfasciatus use accessory gland substances to inhibit remating by females. Crossing experiments were conducted using lines reared on artificial diets or sweet potato tubers during the larval stage, and the refractory period was examined. The results showed that the larval stage diet had a significant effect on the refractory period of females. We also found one protein of approximately 15 kDa in size expressed only in the treatments reared on sweet potatoes. To our knowledge, this is the first study to show that larval diet qualitatively influences male ejaculate and female refractory period. Larval diet significantly affects adult traits, although less is known about how they affect reproductive traits. Males of West Indian sweet potato weevil Euscepes postfasciatus deliver a remating inhibitor along with sperm to their mates during mating, leading to a refractory period (the period before females mate again). Crossing experiments were conducted using lines reared on artificial diets, including sweet potato powder (AD) or sweet potato tubers (SP) during the larval stage, and the refractory period was examined. We also examined whether the larval diet qualitatively or quantitatively altered male ejaculate. The results showed that the refractory period was significantly longer in the SP treatment than in the AD treatment for males and females. There was no significant difference in ejaculate volume. However, the number of sperm in the testes-seminal vesicles complex was significantly higher in the SP treatment. Additionally, SDS-PAGE revealed that the ejaculate was qualitatively different depending on the larval diet, and one protein of approximately 15 kDa in size was expressed only in the SP treatments. Revealing how larval diet affects reproductive traits in adult males will help shed light on the diverse evolution of insect mating systems and reproductive behavior. [ABSTRACT FROM AUTHOR]

Blattisocius mali (Oudemans), known as a predator of some species of storage pest mites, was reared on frozen eggs of Tyrophagus putrescentiae (Schrank) alone (Tp) but also supplemented with cattail (Tp + cattail) and olive (Tp + olive) pollen. Life table parameters of B. mali were evaluated in the first (G1), eighth (G8) and sixteenth (G16) generation on the three different diets. Survival of the immatures of the predator was not affected by the tested diets, whereas it significantly differed among generations. The highest and lowest mortality was observed in the G8 and G1 generations, respectively, on all diets. Except for the total pre-oviposition period (TPOP) and the adult pre-oviposition period (APOP), all life table parameters of B. mali were affected by the different diets; In G1, supplementation of (Tp) with both pollens significantly increased the fecundity, oviposition period and female life span of B. mali. Population growth parameters of the predator like intrinsic rate of increase (r), net reproductive rate (R0) and finite rate of increase (λ) significantly increased with the supplementation of (Tp) with cattail pollen. However, in G8 and G16, B. mali reared on the two combinations significantly showed the lowest values of oviposition period, female and male life span and mean generation time (T) (only F8). Except for female and male developmental times and TPOP, other biological parameters of B. mali significantly differ across generations. Adding both pollens to the frozen eggs of the prey mite, significantly decreased fecundity, oviposition period, female and male life span and population parameters such as (r), (T), (λ) of B. mali in G16 compared with G1. With comparison of the effects of diet through the generations on biological and population parameters of B. mali, it is concluded that frozen eggs of T. putrescentiae is strongly advisable for mass-rearing of the predator and mixed frozen diets (containing pollen) is suggested as supplemental diet for establishment of the predator after release. [ABSTRACT FROM AUTHOR]

The thistle biocontrol beetle, Cassida rubiginosa is established in New Zealand, but often not sufficiently abundant to achieve control of the weed, Cirsium arvense (Californian thistle). Mass production of the beetle could enhance biocontrol efforts through supplemental and inundative releases. We carried out an initial test of a semiartificial diet (containing host plant material) designed for laboratory mass production of the beetle. Larval survival rates were tested on diets with three different concentrations of preservatives (full, half, and no preservative), and compared to a positive control (leaf disc of Cirsium arvense), and a negative control (water). Only larvae on the leaf disc developed to the adult stage. Of the diets, the longest survival time was on the full preservative diet, with a mean mortality time of 8.8 ± 0.6 days, and a maximum survival time of 21 days. Although no larvae completed development on the diets, some important progress was achieved: (1) Neonate larvae were mobile on the diet; (2) larvae fed on the diet; and (3) there was adequate control of microbial contamination without being acutely toxic to the larvae. Further development of a diet for Cassida rubiginosa should focus on nutritional components for larval development. [ABSTRACT FROM AUTHOR]

Cactaceae are among the most problematic invasive alien plants in South Africa, posing serious negative consequences to agriculture and natural ecosystems. Fortunately, South Africa has a long and successful history of controlling cactus weeds using biological control (biocontrol). This paper reviews all the biocontrol programmes against invasive alien Cactaceae in South Africa, focusing on the decade since the last review published in 2011, up to, and including 2020. Biocontrol programmes against 16 target weeds are summarised, all of which rely on either the galling mealybug, Hypogeococcus sp. (Pseudococcidae), or various species or intraspecific lineages of cochineal insects (Dactylopius spp., Dactylopiidae) as agents. New agents are being considered for the three target weed species, Opuntia elata Salm-Dyck, Opuntia megapotamica Arechav. and Trichocereus spachianus (Lem.) Riccob., while permission to release a new agent against Cylindropuntia pallida (Rose) F.M. Knuth has recently been granted. The biocontrol agent, Dactylopius opuntiae (Cockrell) 'stricta', which has been utilised for the successful control of Opuntia stricta Haw., has shown some promise as an agent against one of the worst cactus weeds in the country, the North Cape/Free State variety of Opuntia engelmannii Salm-Dyck. Post-release monitoring and recent observations of the status of control for the 11 other cactus weeds, all of which have well-established agents, are provided. Taxonomic uncertainties and misidentifications of both target weeds and agents has been a constraint to biocontrol efforts, but this has been partially overcome through the use of genetic techniques. Biocontrol is particularly successful in controlling cactus weeds compared to most other taxonomic groups, and it is likely that past successes can be repeated with new target weeds. Mass-rearing and redistribution of agents are essential to gain the maximum possible benefit from cactus biocontrol agents, and recent increases in mass-rearing outputs have been beneficial. [ABSTRACT FROM AUTHOR]

In the mass‐rearing of insects for sterile insect technique (SIT), it is important to maintain the quality of mass‐reared males so that they can compete with wild males in mating with wild females. Mass‐reared insects sometimes have shorter pre‐mating periods and higher mating frequencies than their wild conspecifics. Indeed, this was the case for mass‐reared individuals of the melon fly, Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae), used in the SIT program to eradicate the melon fly on the Southwest Islands of Japan. Therefore, I hypothesized that divergent artificial selection for age at reproduction altered these traits in the melon fly as well. To examine the effects of eggs produced by younger parents on each generation, six artificially selected lines were established, for which eggs were collected from young (Y lines) and old (O lines) females. Then, the pre‐mating periods and mating frequencies in males and females of the selected lines were compared. The results show a decreased pre‐mating period and an increased mating frequency in younger lines compared to older lines, which was driven by males rather than females. These traits ensure efficient offspring production in mass‐rearing, and are likely advantageous to the success of SIT programs. The impact of artificially selecting for these traits, especially in males, on insect quality and the efficiency of SIT is discussed. [ABSTRACT FROM AUTHOR]

In Sterile Insect Technique (SIT) programs, massive numbers of insects are reared, sterilized, and released in the field to impede reproduction of pest populations. The domestication and rearing processes used to produce insects for SIT programs may have significant evolutionary impacts on life history and reproductive biology. We assessed the effects of domestication on sexual performance of laboratory reared Queensland fruit fly, Bactrocera tryoni, by comparing an old (49 generations) and a young colony (5 generations). We evaluated mating propensity, mating latency, copula duration, sperm transfer, and ability to induce sexual inhibition in mates. Overall, both males and females from the old colony had greater mating propensity than those from the young colony. Copula duration was longer when females were from the old colony. There was no evidence of sexual isolation between the colonies as males and females from the two colonies had similar propensity to mate with flies from either colony. Males from the old colony transferred more sperm regardless of which colony their mate was from. Finally, males from both colonies were similarly able to induce sexual inhibition in their mates and were also similarly able to secure copulations with already‐mated females. Positive effects of domestication on sperm transfer, coupled with maintained ability to induce sexual inhibition in mates and to secure copulations with previously mated females, highlights that domestication may have little effect, or even positive effects, on some aspects of sexual performance that may advantage mass‐reared B. tryoni in SIT programs. [ABSTRACT FROM AUTHOR]

The endosymbiotic bacterium Wolbachia is being developed as a tool to suppress mosquito populations and their transmitted pathogens, with successful field trials in multiple countries having resulted in efforts to scale up the capacity to mass-produce mosquitoes for release. However, major challenges exist to achieving this goal, including concerns that mass-reared mosquitoes will adapt to laboratory conditions during long-term maintenance and experience inbreeding depression, resulting in poor performance of the released mosquitoes in the field. Here, we assessed the performance of the Aedes albopictus HC line infected with a triple-strain Wolbachia after mass-rearing at scaled-up densities of up to 15 million mosquitoes per week for over 50 generations. In comparison with the wild-type GUA line, the HC mosquitoes had desirable characteristics for mass-rearing and release, including robust male mating competitiveness, high female reproductive capacity, reduced vector competence for dengue virus, and increased Wolbachia density. Although the larval survival rate of the HC and GUA lines was similar, the HC larvae developed significantly faster, possibly because of up-regulation of the molting hormone 20-hydroxyecdysone-related gene E75 in the HC larvae. Our results indicate that over many generations mass-reared mosquito lines can retain their quality if large effective population sizes with sufficient genetic heterogeneity are maintained under optimized rearing conditions and demonstrate the long-term feasibility of deploying Wolbachia-based approaches for area-wide management of mosquito vectors for disease control. [ABSTRACT FROM AUTHOR]

Five separate diets – beeswax (BW), glycerol (Gly), and three types of dog croquettes (DC1, DC2, and DC3) – were used to rear larvae of the greater wax moth, Galleria mellonella. The larvae were later inoculated with five different isolates of entomopathogenic nematodes (EPN) emerging from the insect larvae reared on the five diets. Insect cadavers were then conserved for 1, 2, 3, and 4 wks (T1, T2, T3, and T4, respectively) to evaluate the nematodes’ progeny production and to assess the pathogenicity of emerging nematodes to G. mellonella larvae. Larvae fed on DC1 weighed the least (0.18 ± 0.03 g) and those fed on Gly weighed the most (0.22 ± 0.04 g). Gly was effective for insect development but was the most expensive to produce at 6.30 US dollars/kg. No significant difference (P = 0.851) was observed between mortality rates of larvae for nematode isolates for the three best diets (Gly, BW, and DC1) during 1 wk (T1) and 3 wks (T3) after processing at 3 d post-inoculation. All nematode isolates emerged and had the highest population density per insect larva at T1 for isolate Ze4 (Heterorhabditis sonorensis) on BW (553.63 ± 311.97 infective juveniles (IJs)/50 μ l of suspension, 276,815 IJs/larva) and at T2 on DC1 (488.63 ± 321.37 IJs/50 μ l, 244,315 IJs/larva) and for isolate Aglali (H. sonorensis) at T1 on Gly (615.18 ± 309.63 IJs/50 μ l, 307,590 IJs/larva). This study shows the costs and effectiveness of different diets on development and production of G. mellonella larvae and the EPN produced in vivo.

Phytoseiid predatory mites are the most important group of biocontrol agents currently used in protected cultivations worldwide. The possibility to produce these predators at high densities on factitious prey mites is a crucial factor for their success. Commonly used factitious prey mites comprise mainly species belonging to the cohort of Astigmatina. In the present study, we investigated the potential of tarsonemid prey mites as a food source for the spider mite predator Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). The oviposition of N. californicus on mixed stages of Tarsonemus fusarii Cooreman (Acari: Tarsonemidae) was similar to that on its natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). As most tarsonemids are specialized fungus-feeders, we tested the effect of different fungal species on the growth of T. fusarii. Subsequently, we analysed the impact on the fungal growing medium on the oviposition of N. californicus. The fungal growing medium of T. fusarii had a significant negative effect on the reproductive output of the predatory mite. When T. fusarii was separated from the rearing medium, these detrimental effects were not observed. The present study shows the potential of using tarsonemid prey mites in the production of phytoseiid predatory mites. [ABSTRACT FROM AUTHOR]

Larval diet significantly affects adult traits, although less is known about how they affect reproductive traits. Males of West Indian sweet potato weevil Euscepes postfasciatus deliver a remating inhibitor along with sperm to their mates during mating, leading to a refractory period (the period before females mate again). Crossing experiments were conducted using lines reared on artificial diets, including sweet potato powder (AD) or sweet potato tubers (SP) during the larval stage, and the refractory period was examined. We also examined whether the larval diet qualitatively or quantitatively altered male ejaculate. The results showed that the refractory period was significantly longer in the SP treatment than in the AD treatment for males and females. There was no significant difference in ejaculate volume. However, the number of sperm in the testes-seminal vesicles complex was significantly higher in the SP treatment. Additionally, SDS-PAGE revealed that the ejaculate was qualitatively different depending on the larval diet, and one protein of approximately 15 kDa in size was expressed only in the SP treatments. Revealing how larval diet affects reproductive traits in adult males will help shed light on the diverse evolution of insect mating systems and reproductive behavior.

The yellow mealworm, Tenebrio molitor L. is one of the most significant insect species of economic importance for producing protein-rich food and feed. The larvae are a promising fishmeal substitute for fish feed, and a good alternative source for human nutrition. In this study, the effect of behavioral asymmetries on male mating success of T. molitor was evaluated. Males performing antennal waving (63%) when detecting a female approached the apex of the female abdomen in a comparable manner from both sides (32% from left side vs 31% from right side). Fewer males showed antennal waving and also raised the anterior part of their body (37%) during mate recognition; 14% of them approached on the apex of female abdomen from the left side, and 23% of them approached from the right side of female body. The duration of mate recognition, antennal tapping, rubbing behavior, and the whole mating sequence of males that moved on the apex of the abdomen from the left side of females was significantly lower over that of males approaching from the right side (10.7, 12.6, 16.4, and 126.1 s for left-biased males vs 12.2, 14.8, 18.6, and 139.6 s for right-biased males, respectively). Concerning mounting side, left-biased males showed a shorter duration of rubbing behavior and the whole mating sequence (15.5 and 123.2 s) over right-biased (18.9 and 138.3 s) and backside approaching males (19.4 and 144.1 s). The duration of mate recognition, antennal tapping, and copula was not affected by the presence of a male laterality bias. Overall, this study sheds light on how laterality affects mating traits and the male success of this important edible insect species. [ABSTRACT FROM AUTHOR]

BACKGROUND Like numerous other animals, biocontrol agents (BCAs) of arthropod pests carry various microorganisms that may have diverse effects on the biology of their eukaryote hosts. We postulated that it is possible to improve the efficacy of BCAs by manipulating the composition of their associated microbiota. The parasitoid wasp Anagyrus vladimiri (Hymenoptera: Encyrtidae) from a mass‐rearing facility was chosen for testing this hypothesis. RESULTS: High‐throughput sequencing analysis indicated that fungal abundance in A. vladimiri was low and variable, whereas the bacterial community was dominated by the endosymbiont Wolbachia. Wolbachia was fixed in the mass‐rearing population, whereas in field‐collected A. vladimiri Wolbachia's prevalence was only approximately 20%. Identification of Wolbachia strains from the two populations by Multi Locus Sequence Typing, revealed two closely related but unique strains. A series of bioassays with the mass‐rearing Wolbachia‐fixed (W+) and a derived antibiotic‐treated Wolbachia‐free (W–) lines revealed that: (i) Wolbachia does not induce reproductive manipulations; (ii) W– females have higher fecundity when reared individually, but not when reared with conspecifics; (iii) W+ females outcompete W– when they share hosts for oviposition; (iv) longevity and developmental time were similar in both lines. CONCLUSIONS: The findings suggest that W+A. vladimiri have no clear fitness benefit under mass‐rearing conditions and may be disadvantageous under lab‐controlled conditions. In a broader view, the results suggest that augmentative biological control can benefit from manipulation of the microbiome of natural enemies. [ABSTRACT FROM AUTHOR]

Campoplex capitator is an ichneumonid parasitoid with a narrow host range, comprising grapevine moth pests. Despite being considered one of the possible candidates for biocontrol of Lobesia botrana, knowledge about its biology is limited and mass‐rearing for commercial purposes is still lacking. This research provides a quantitative analysis of the C. capitator courtship and mating behavior. C. capitator mating sequence was analyzed by high‐speed video recordings. Main behavioral parameters, with special reference to male wing fanning and antennal tapping, were quantified and linked with mating success. Furthermore, we analyzed the occurrence of population‐level behavioral asymmetries during C. capitator sexual interactions and their impact on male success. Results showed that male wing fanning was crucial to successfully approach the female. Males achieving higher mating success performed wing‐fanning at higher frequencies over unsuccessful ones. After wing fanning, most of males palpated the female's body with their antennae, before attempting copulation. The overall mating success was >70%, with a rather long copula duration (254.76 ± 14.21 s). Male wing‐fanning was lateralized on the left at population level, while antennal tapping displays were right‐biased. Side‐biased male displays do not differ in terms of frequency and duration of their main features. This research adds basic knowledge to the C. capitator behavioral ecology. Since rearing protocols for C. capitator are being developed, male wing fanning frequency may represent a useful benchmark for monitoring mate quality over time, tackling mating success reductions due to prolonged mass‐rearing. [ABSTRACT FROM AUTHOR]

• The development and reproductivity of C. sasakii on two apple varieties was studied. • C. sasakii on Golden Delicious apple has higher harvest rate and potential harm. • Golden Delicious apple is the better economical choice for the mass-rearing system. Carposina sasakii Matsumura (Lepidoptera: Carposinidae), is one of the most serious fruit-boring pests in over ten species of fruit trees, and is especially damaging apples in the northern of China. The application of new planting systems, i.e., high-density and dwarfing rootstock orchard systems with mixed apple varieties, makes it important to study the fitness of C. sasakii on these apple varieties to gain fundamental knowledge for use in pest management involving this insect. In this study, life table data of C. sasakii were collected using Golden Delicious and Red Fuji apples as hosts. The egg-larva duration of male C. sasakii reared on Golden Delicious apples (22.81 d) was significantly shorter than that reared on Red Fuji apples (24.27 d). The egg-larva mortality in Golden Delicious apples (59.00%) was lower than that in Red Fuji apples (72.49%). The mortality of the pupal stage, however, was higher in Golden Delicious (10.51%) than in Red Fuji (0%). The total oviposition period (TPOP) on Golden Delicious apples (32.94 d) was significantly shorter than in individuals reared on Red Fuji apples (34.19 d). The intrinsic rate of increase (r = 0.0581 d−1), net reproductive rate (R 0 = 7.57 offspring), and finite rate of increase (λ = 1.0598 d−1) were all higher on Golden Delicious than those on Red Fuji. When the net reproductive rate (R 0) was used, the harvest rate of pupae was higher (0.8678) when reared on Golden Delicious apples than when reared on Red Fuji apples (0.8398). When a large cohort size (n = 200) was used for effective bootstrap sample, the P E values for C. sasakii reared on Golden Delicious apples and Red Fuji apples were both almost equal to 1. For C. sasakii culturing purposes, Golden Delicious apples would be more productive than Red Fuji. [ABSTRACT FROM AUTHOR]

Abstract Background In a context of increasing resistance of both vectors toward main classes of insecticides used in public health and parasites toward anti-malarial drugs, development of new and complementary molecules or control approaches is fundamental to achieve the objective of controlling or even eliminating malaria. Concerning vector control, the sterile insect technique and other genetic control approaches are among promising complementary tools in an integrated management strategy for malaria control. These approaches rely not only on a good understanding of vector biology (especially during larval stages), but also on the availability of adequate supplies and protocols for efficient mosquito rearing. The aim of this study was to assess the factors impacting the life history of Anopheles coluzzii mosquitoes at the larval stage, in the context of genetic and sterile insect approaches to control malaria vectors. Methods The effect of different larval diets and larval rearing densities on the development of An. coluzzii were evaluated in the laboratory. Emergence rate (ER), pre-imaginal developmental time (DT) and adult wing length (WL) were measured under different food regimes. Four diets were tested among which three were provided by the Insect Pest Control Laboratory (IPCL) of the FAO/IAEA Joint division. Results Data showed significant differences in the quality of the different diets and suggested a negative density dependence in all three life history parameters measured under tested rearing conditions. ER and WL increased with food availability, but decreased with increasing larval density. Conversely DT was shortened with increasing food availability but increased with larval density. These data demonstrates intraspecific larval competition modulated by food amount and space availability. Of the four diets tested, the one made of a mix of tuna meal, bovine liver powder, brewer’s yeast, squid liver powder and vitamin mix (diet 2) yielded the best results as it produced a good balance between ER, DT and WL. Food availability for optimal development (highest survival at shortest time) was in the range of 180–400 µg/larvae/day for the three diets provided by the IPCL. Conclusion There is an interaction between diet type, diet concentration and larval density. Best results in terms of optimal larvae development parameters happen when moderately high values of those three variables are observed.

Mass rearing the black soldier fly, Hermetia illucens, for waste bioremediation and valorisation is gaining traction on a global scale. While the health and productivity of this species are underpinned by associations with microbial taxa, little is known about the factors that govern gut microbiome assembly, function, and contributions towards host phenotypic development in actively feeding larvae. In the present study, a 16S rDNA gene sequencing approach applied to a study system incorporating both feed substrate and genetic variation is used to address this knowledge gap. It is determined that the alpha diversity of larval gut bacterial communities is driven primarily by features of the larval feed substrate, including the diversity of exogenous bacterial populations. Microbiome beta diversity, however, demonstrated patterns of differentiation consistent with an influence of diet, larval genetic background, and a potential interaction between these factors. Moreover, evidence for an association between microbiome structure and the rate of larval fat accumulation was uncovered. Taxonomic enrichment analysis and clustering of putative functional gut profiles further suggested that feed-dependent turnover in microbiome communities is most likely to impact larval characteristics. Taken together, these findings indicate that host–microbiome interactions in this species are complex yet relevant to larval trait emergence.

We established a method for mass-rearing the stone leek leafminer, Liriomyza chinensis (Kato) (Diptera: Agromyzidae), one of the most destructive pests of Welsh onion, Allium fistulosum L. We examined three methods that allow L. chinensis to produce eggs year-round. By recording the number of emerged adults for 4 years, we determined the optimal mass-rearing method as follows. Allium fistulosum plants used for oviposition are grown in pots and maintained in a growth chamber with temperature and photoperiod set to 22 ℃ and 14 L:10 D, respectively. Allium fistulosum plants are exchanged for a new set of plants three times in a 7-day period. On the first day, 300 adults are placed in the rearing cage. On the fifth day, another 100 emerged adults are placed in the rearing cage. Using this rearing method, it becomes possible to obtain more than 1,000 L. chinensis eggs in a day. Our goal is to select and breed a highly resistant line of A. fistulosum using a novel method for evaluating egg killing defenses via artificial inoculation of plants with L. chinensis eggs. Here we present our mass-rearing method to obtain large quantities of L. chinensis eggs. [ABSTRACT FROM AUTHOR]

Queensland fruit fly [Bactrocera tryoni (Froggatt), Diptera, Tephritidae] is the most devastating insect pest impacting Australian horticulture. The Sterile Insect Technique (SIT) is an important component of tephritid pest management programs. However, mass‐rearing and irradiation (to render insects sterile) may reduce the fitness and performance of the insect, including the ability of sterile males to successfully compete for wild females. Manipulation of the gut microbiome, including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass‐reared sterile flies, however there are fewer published studies targeting the larval stage. In this study, we supplemented the larval stage of mass‐reared B. tryoni with bacterial probiotics. We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B. tryoni larvae including Asaia sp., Enterobacter sp., Lactobacillus sp., Leuconostoc sp. We also tested a consortium of all four of these bacterial isolates. The fitness parameters tested included adult survival in field cages, laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females, and laboratory locomotor activity of adult flies. None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival, mate selection or locomotor activity of adult B. tryoni, which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids. Future work is needed to determine if feeding the same, and/or other probiotics to adults, as opposed to larvae can positively impact survival, mating performance, mating competitiveness and locomotor activity of B. tryoni. The bacterial group(s) and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass‐rearing programs. [ABSTRACT FROM AUTHOR]

Diet is a critical component of the mass-rearing of biological control agents, but the impacts of diet are not always immediately obvious and can take several generations to manifest, resulting in poor survival, reproduction, and ability to kill prey under natural conditions. Our present study aimed to investigate the performance of a commercially-reared phytoseiid mite, Amblyseius swirskii, after four (G4) and six (G6) consecutive generations on pollen grains of two plant species, as well as its ability to find and kill its natural prey, Tetranychus urticae, after long-term rearing on each diet. We found no significant difference between the two diets in intrinsic and finite rates in G4. However, both diet and generation exerted a significant influence on the fecundity of A. swirskii. By G6, females reared on almond pollen had greater net reproductive and intrinsic rate compared to those reared on maize pollen. Conversely, A. swirskii fed on maize pollen consumed fewer prey than those reared on other diets, especially at higher prey densities. The findings have important implications for developing the mass-rearing program of A. swirskii on non-prey diets. Further research must explore the suitability of almond pollen in the large-scale culture of A. swirskii. [ABSTRACT FROM AUTHOR]