In the context of climate change and depletion of natural resources, meeting the growing demand for animal feed and human food through sufficient, nutritious, safe, and affordable sources of protein ...is becoming a priority. The use of Hermetia illucens , the black soldier fly (BSF), has emerged as a strategy to enhance the circularity of the agri-food chain, but its microbiological safety remains a concern. The aim of the present study was to systematically review available data on the microbiological quality of BSF and to investigate the impact of using four different rearing substrates including classic options allowed by the EU regulation (cereals, fruits, vegetables) and options not allowed by EU regulations regarding vegetable agri-food (co-products, food at shelf life, and meat). A total of 13 studies were collected and synthesized, including 910 sample results, while 102 new sample results were collected from the present experiments in three farms. Both datasets combined revealed a high level of contamination of larvae, potentially transmitted through the substrate. The main pathogenic bacteria identified were Bacillus cereus , Clostridium perfringens , Cronobacter spp., Escherichia coli , Salmonella spp., and Staphylococcus aureus coagulase-positive, while Campylobacter spp. and Listeria monocytogenes were not detected. Any of these four substrates were excluded for their use in insect rearing; however, safety concerns were confirmed and must be managed by the operators of the sector using microbial inactivation treatment after the harvest of the larvae in order to propose safe products for the market. The results obtained will guide the definition of the control criteria and optimize the following manufacturing steps.
The brown stink bug, Euschistus heros, is a key pest affecting soybean crops in Brazil and other South American countries. Temperature plays a crucial role in insect development and reproduction; ...however, little is known about temperature on E. heros' fitness. This study examined the effects of both constant and fluctuating temperatures on E. heros' biological characteristics across three generations. Development did not occur at constant temperatures of 19 °C and 34 °C, and at 31 °C, there was no reproduction. Development duration was faster at warmer constant temperatures, but fluctuating temperatures decreased E. heros' egg viability. This research allowed the development of temperature base and degree day requirements for each E. heros stage and revealed that about 40% mortality occurs during molting, with the highest mortality between first and second-stage nymphs. Together, these data improve the management of E. heros and benefit the mass production of egg parasitoids used for its control. The brown stink bug, Euschistus heros (Fabricius, 1798) (Hemiptera: Pentatomidae), is one of the most abundant soybean stink bug pests in Brazil. Temperature is a key factor that affects its development and reproduction, and fluctuating temperatures may impact the development and reproduction of E. heros differently from those under constant temperatures. The objective of this study was to evaluate the influence of constant and fluctuating temperature on the biological characteristics of E. heros in three successive generations. Treatments consisted of six constant temperatures (19 °C, 22 °C, 25 °C, 28 °C, 31 °C and 34 °C) and four fluctuating temperatures (25:21 °C, 28:24 °C, 31:27 °C, and 34:30 °C) evaluated for three successive generations. Second-stage nymphs were evaluated daily, and after they reached the adult stage, they were separated by sex, and the individual weight (mg) and pronotum size (mm) were recorded. After pair formation, eggs were collected to evaluate the pre-oviposition period, total number of eggs, and egg viability. The duration of the nymphal stage was reduced with an increase in both constant and fluctuating temperatures; however, at constant temperatures of 19 °C, 31 °C and 34 °C and fluctuating temperatures of 28:24 °C, there was no reproduction in adults. The base temperature and total degree day requirement for nymphal development were 15.5 °C and 197.4 dd, respectively. Pre-oviposition period (d), number of eggs per female, and viability of eggs (%) were affected by temperature across the generations. The multiple decrement life table analysis revealed that mortality was highest during the molting of the second-stage nymphs. These findings have important implications for E. heros' laboratory mass-rearing programs and for its management in fields.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Biological control programs are used to effectively manage pests in a more sustainable way, such as the case of the microwasp parasitoid Telenomus podisi for managing eggs of the brown stink bug ...Euschistus heros, a key pest in South American soybean. A biological control program requires continuous production of the parasitoids and thus, artificial diets and freezing of host eggs are necessary. We evaluated the parasitism capacity of T. podisi reared on fresh or previously frozen eggs from E. heros fed on natural or two artificial diets. Seven constant temperatures were tested for each condition. We measured biological parameters of wasps and the rates of parasitism. We found that 24 °C had better parasitism and viability parameters, and was most-favorable to T. podisi production. We also found that both tested artificial diets for E. heros produced eggs that support mass rearing of this egg parasitoid. The parasitoid Telenomus podisi Ashmead, 1893 is used in biological control programs in Brazil against eggs of Euschistus heros (Fabricius, 1798), a key pest of soybean, Glycine max (L.) Merr. To optimize the mass production of parasitoids, artificial diets and storage of host eggs at low temperatures have been developed; however, direct comparisons of the effects of these conditions have not occurred. We assessed a double factorial arrangement composed of six treatments (fresh or cryopreserved E. heros eggs from adults fed on natural or two artificial diets). We evaluated the biological characteristics and parasitism capacity of T. podisi produced from these treatments across seven temperatures. The thermal range between 21 and 30 °C resulted in satisfactory daily parasitism in all treatments tested, with an inverse relationship between temperature and female survival. The best parasitoid biological parameters were found between 21 and 27 °C, where all tested diets supported T. podisi development, with the best results from artificial diets. Fresh eggs and those frozen in liquid nitrogen and stored at −196 °C until use supported parasitoid development. These results suggest that the best method to mass rear T. podisi is to use artificial diets to rear E. heros and store eggs until needed, and then rear parasitoids at 24 °C.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Rearing common bed bugs (Cimex lectularius L.) and other hematophagous insects is essential for basic, medical, and pest-control research. Logistically, acquiring fresh blood can be a challenge, ...while biologically, the eventual effects of different rearing and blood preparation protocols on bed bug genotype and phenotype pose a risk of biased research results. Using bed bug populations that are either bat- (BL) or human-related (HL), we tested the short- and long-term effects of rearing bugs on live bats or human volunteers, or artificially on CPDA (citrate phosphate dextrose, adenine)-treated blood, measuring meal size, body size, and fertility. We found that artificial feeding did not affect meal size compared with feeding on natural hosts. Long-term rearing across many generations of HL on CPDA-preserved blood led to reduced body size and fertility compared with populations reared on human volunteers. Blood preservatives increased the proportion of sterile eggs even after a single feed. Finally, our results indicated that laboratory reared bed bugs were smaller, regardless of the blood source, than wild bugs. Similar effects of artificial feeding or laboratory rearing alone should be considered in future studies using bed bug cultures to choose an appropriate rearing protocol. With regard to switching between bat and human hosts, HL took smaller meals and BL had lower fertility when fed on bats than when fed on humans. We attribute these results to methodological constrains, specifically the inconsistency of bat feeding, rather than to host specialization. Nevertheless, BL can be easily reared using human blood and artificial feeding systems.
Growing insects on agricultural wastes is an approach to reduce the amount of waste produced by farming operations and convert it into valuable products such as protein (for food and feed) and ...fertilisers. The larvae of two insects were fed with substrates that contain hemp residues (welted flowers, old leaves, and stalks) and were able to grow. The produced black soldier fly larvae did not contain the psychoactive ∆-9-tetrahydrocannabidiol (∆sup.9 -THC) and contained beneficial cannabinoids such as cannabidiol (CBD), and the amounts were minimal in comparison to the amount found in the initial substrate before given to the larvae. Mealworms were grown on hemp material that is rich in bioactive compounds, none of which was detected in the produced larvae. This study demonstrates that hemp agricultural wastes can be used as feed for these two insects, and the produced larvae do not contain the psychoactive compounds of hemp. The proper treatment of cannabis agricultural wastes can reduce the environmental impact of its cultivation and generate valuable products. This study aimed to test the potential of cannabis agricultural wastes as a substrate for the rearing of black soldier fly larvae (BSFL) and yellow mealworms (MW). In the case of BSFL, replacing the fibre component (straw) in the substrate with the hemp waste can increase the nutritional value of the substrate and led to bigger larvae. The bigger larvae had lower P and Mg, and higher Fe and Ca. Crude protein also varied based on the size of larvae and/or the content of protein in the initial substrate, which was boosted by replacing straw with hemp material. No other cannabinoids than cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), and cannabidiol (CBD) were found in significant amounts in the larvae. In the case of MW, the larvae grew less on the hemp material in comparison to wheat bran. Replacing wheat bran with the hemp material led to smaller larvae with higher Ca, Fe, K, and crude protein content, but lower Mg and P values. No cannabinoids were detected in the MW fed with the hemp material.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The sweetgum inscriber Acanthotomicus suncei is a newly described pest of American sweetgum in China, which could cause extensive damage to the native flora if this beetle becomes established in ...North America. Research on the beetle has been hampered by a dwindling access to breeding material. Therefore, the aim of this study was to discover a cost-effective way to rear A. suncei. An artificial diet with small amounts of additives supported the shortest development time, whereas rearing the beetles on natural American sweetgum logs led to a longer development time. The lengths and weights of adults reared on the artificial diet were markedly higher than those of adults reared on American sweetgum logs. The egg hatching and eclosion rates of A. suncei reared on the artificial diet were significantly higher than those on sweetgum logs. However, the pupation rate of A. suncei on the artificial diet was much lower than that on sweetgum logs. In summary, our artificial diet supports a rapid buildup of a healthy A. suncei lab population. The sweetgum inscriber, Acanthotomicus suncei (Coleoptera: Curculionidae: Scolytinae), is a recently discovered pest of American sweetgum planted in China, with a potential for causing a devastating invasion into North America. Research on the beetle has been hampered by a dwindling access to breeding material. We tested the effect of four artificial diets on A. suncei’s developmental time, length and weight of adults, egg hatching rate, pupation rate, and eclosion rate. Additionally, we evaluated the same parameters on A. suncei reared on American sweetgum logs. Only one diet supported the full development of A. suncei after 30 d. Beetles reared on this diet, which was made of small quantities of agar and additives (i.e., inositol, potassium sorbate, and methylparaben), supported the shortest developmental time of 45.55 ± 1.24 d. Beetles reared on American sweetgum logs exhibited a longer developmental time of 59.52 ± 4.52 d. Beetles reared on the artificial diet were markedly bigger and heavier than those reared on American sweetgum logs (p < 0.01). The egg hatching rate (58.90% ± 6.80%) and eclosion rate (86.50% ± 4.69%) of A. suncei on the artificial diet were significantly greater than those on sweetgum logs. However, the pupation rate (38.60% ± 8.36%) was much lower on the artificial diet than on the sweetgum logs. Here, we reported the best artificial diet for A. suncei and discuss the advantages and disadvantages over rearing the beetle on American sweetgum logs.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract
Brazil has a long history of the use of biological control (BC) of pests. The first attempt to use parasitoids was reported in the 1930s, and the first successful case dates to 1967. For a ...long period, chemical products were the most widespread control measure among Brazilian growers. This situation has gradually changed because of the lack of satisfactory control to manage certain pests, a slow change in the culture of growers, and some emblematic cases of the successful use of BC. The use of BC as a component of Integrated Pest Management is increasingly common. The present contribution summarizes the evolution of BC in Brazil, citing as an example the case of successful use of Cotesia flavipes (Cameron) (Hymenoptera: Braconidae), Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) and Trichogramma spp. It presents some data on the utilization of BC in the country, such as the case of sugarcane, for which microorganisms as well as macroorganisms are used; the use of Baculovirus in soybean, produced in mass-reared lepidopteran larvae; and the recent case of the control of Diaphorina citri Kuwayama (Hemiptera: Liviidae) by the parasitoid Tamarixia radiata. Finally, the prospects for wider use of BC in Brazil are discussed, together with the challenges involved in broadening the growers’ use of this technology.
Megachile cephalotes is a solitary bee that is widely distributed in Sindh and Punjab, Pakistan. It has been reported as an effective pollinator of Grewia asiatica and some other crops. Bees are ...declining around the world, threatening the productivity of field crops, vegetables, and fruits. Among the Megachilini tribe, the only European leaf-cutting bees, Megachile rotundata has been artificially reared and conserved on a commercial scale in different parts of the world. Some recent studies have shown a high pollination potential of M. cephalotes owing to its gregarious nesting and foraging behavior. In the present study, the nesting biology and ecology of M. cephalotes were reported for the first time in this region. The bees remained active during the spring and summer seasons, and females preferred to construct their nests in bamboo sticks and wooden blocks. They used plant resin for the construction of brood cells and placed several types of pollen grains in these cells. The males took fewer days to become adults than the females. The present study will help in the commercial-scale artificial nesting and conservation of M. cephalotes. We report the nesting biology and ecology of Megachile cephalotes Smith, 1853 for the first time in Pakistan. Wooden and bamboo trap nests were deployed at three different locations in Bahawalpur district, Pakistan, from January 2020 to May 2021. A total of 242 nests of M. cephalotes were occupied in all three locations with the maximum abundance in the Cholistan Institute of Desert Studies. Megachile cephalotes remained active from March to September (the spring and summer seasons). In a nest, females made 7–8 brood cells each having a length of 1.2–2.3 cm. Plant resin was used to construct cells and mud or animal dung to plug the nest entrance. A vestibular cell was also made between the outermost brood cell and the nest entrance that ranged from 1.4 to 2.5 cm in length. No intercalary cells were observed in the nests. The males took 65.3 days to become adults, while the females took 74.78 days. The sex ratio was significantly biased toward females in all three locations. Grewia asiatica was the predominant pollen grain species found in the brood cells. Megachile cephalotes were observed collecting resin from Acacia nilotica, Prosopis juliflora, and Moringa oleifera. Three cleptoparasites of this species were also recorded: Euaspis carbonaria, Coelioxys sp., and Anthrax sp. This study set up a background to encourage new studies on artificial nesting and provides tools for proper biodiversity management and conservation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A method for rearing the southern green stinkbug, (Nezara viridula L.Heteroptera: Pentatomidae), using a modified lygus semi-solid artificial diet was developed. First to second-instar nymph were ...reared in a density of 631.5 + or - 125.05 eggs per Petri-dish (4 cm deep * 15 cm diam). Second instar to adult were reared in a density of 535.0 + or - 112.46 s instar nymphs per rearing cage (43 * 28 * 9 cm). Mating and oviposition occurred in popup rearing cages (30 * 30 cm), each holding 60-90 mixed sex adults of similar age. Adults emerged 35.88 + or - 2.13 d after oviposition and survived for an average of 43.09 + or - 9.53 d. On average, adults laid 223.95 + or - 69.88 eggs in their lifetime, for a total production of 8,099 + or - 1,277 fertile eggs/oviposition cage. Egg fertility was 77.93% + or - 16.28. Egg masses held in petridishes had a total hatchability of 79.38% + or - 20.03. Mortality of early nymphs in petri-dishes was 0.64% + or - 0.12 for the first instar and 1.37% + or - 0.45 for second instar. Late nymphal mortality in rearing cages was 1.41% + or - 0.10, 3.47% + or - 1.27, and 4.72% + or - 1.29 for the third, fourth, and fifth instars, respectively. Survivorship from nymphs to adults was 88.48% + or - 2.76. Using artificial diet for rearing N. viridula could reduce cost by avoiding time-consuming issues with daily feeding fresh natural hosts and insect manipulation. It could increase reliability and simplicity of bug production, which should facilitate mass rearing of its biological control agents.
Globally, the expansion of livestock and fisheries production is severely constrained due to the increasing costs and ecological footprint of feed constituents. The utilization of black soldier fly ...(BSF) as an alternative protein ingredient to fishmeal and soybean in animal feed has been widely documented. The black soldier fly larvae (BSFL) used are known to voraciously feed and grow in contaminated organic wastes. Thus, several concerns about their safety for inclusion into animal feed remain largely unaddressed. This study evaluated both culture-dependent sequence-based and 16S rDNA amplification analysis to isolate and identify bacterial species associated with BSFL fed on chicken manure (CM) and kitchen waste (KW). The bacteria species from the CM and KW were also isolated and investigated. Results from the culture-dependent isolation strategies revealed that
Providencia
sp. was the most dominant bacterial species detected from the guts of BSFL reared on CM and KW.
Morganella
sp. and
Brevibacterium
sp. were detected in CM, while
Staphylococcus
sp. and
Bordetella
sp. were specific to KW. However, metagenomic studies showed that
Providencia
and
Bordetella
were the dominant genera observed in BSFL gut and processed waste substrates.
Pseudomonas
and
Comamonas
were recorded in the raw waste substrates. The diversity of bacterial genera recorded from the fresh rearing substrates was significantly higher compared to the diversity observed in the gut of the BSFL and BSF frass (leftovers of the rearing substrates). These findings demonstrate that the presence and abundance of microbiota in BSFL and their associated waste vary considerably. However, the presence of clinically pathogenic strains of bacteria in the gut of BSFL fed both substrates highlight the biosafety risk of potential vertical transmission that might occur, if appropriate pre-and-postharvest measures are not enforced.
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