Effective bioconversion of farmed chicken products by black soldier fly larvae at commercially relevant growth temperatures

Global population growth and an increasing demand for meat has driven the intensification of livestock production. On poultry farms, the accumulation of waste such as faeces, carcasses and unsellable eggs creates environmental and health hazards that need to be mitigated. The larvae of the black soldier fly (Hermetia illucens; BSFL) offer a potential solution to the problems of waste management on poultry farms. BSFL consume large quantities of organic waste and convert it into larval biomass, which can then be processed for use as livestock feeds or biofuels. This makes BSFL an ideal candidate for value-added waste management on chicken farms. Here, we examined the development and nutrient profile of BSFL given five different diet treatments: poultry feed (control), chicken meat, chicken egg, chicken manure and a mixture of equal parts chicken meat, egg and manure. Chicken meat, egg and mixed diets were all found to be suitable feedstocks for BSFL, but the manure-only treatment was associated with a high failure rate of larval development. Mixing manure with other poultry waste streams ameliorated the negative impacts of manure on BSFL. Larvae reared on chicken meat, egg and the mixed diet had equal or higher mean crude protein (CP) (39.9%, 33.8% and 31.5%, respectively) and crude lipid (CL) contents (30.1%, 29.00% and 28.7%, respectively), compared with BSFL reared exclusively on chicken feed (CP: 30.9%, CL: 23.8%), demonstrating the suitability of these waste-stream diets for the potential animal feed quality of the BSFL. We discuss how BSFL bioconversion could be implemented to address environment management issues on poultry farms.     

Black soldier fly larvae show a stronger preference for manure than for a mass-rearing diet

The attention for black soldier fly larvae (BSFL) as an alternative ingredient for food and feed products is on the rise. While many studies have reported the efficiency of BSFL to bio-convert a wide range of organic waste streams into larval biomass, so far, it is unknown whether BSFL prefer certain waste streams over others when they have the possibility to choose. Here, we performed a choice-test experiment to explore the preference of BSFL when exposed to pig manure and a mass-rearing diet consisting of plant by-products currently used for industrial BSFL production. We found that after 1 hr of exposure to both feeds, BSFL strongly preferred pig manure over the mass-rearing diet. The preference for manure became stronger as larval age increased. Our results provide the first evidence that BSFL express a distinct diet preference. Understanding the reasons for the strong preference for manure is relevant for a diverse array of practical applications and to inform the discussion on insect welfare.     

Effects of food substrates and moxidectin on development of black soldier fly,Hermetia illucens

Black soldier fly is a common and widely distributed saprophagous species that has an excellent potential for being used for biological conversion of organic wastes on an industrial scale. The main goal of the reported study was expanding the list of wastes suitable for utilization by this species. We compared larval growth on cull potatoes, horse manure and cafeteria food waste in 100‐L bins in a greenhouse. We also conducted laboratory experiments to investigate whether black soldier fly larvae are affected by the presence of moxidectin, a common endectocide used to treat an array of domestic animals and readily excreted in faeces, in their food substrates. Feeding on potatoes resulted in slower growth, and the final size of potato‐fed larvae was smaller compared to the larvae fed on cafeteria waste. Nevertheless, potatoes supported substantial biomass accumulation, and could be a valuable option for rearing fly larvae for commercial feed production. Larvae feeding on horse manure gained very little weight and eventually failed to pupate. Moxidectin had a strong negative effect on larval survivorship; however, ca. 30% of larvae reared in the substrate containing a realistic field concentration of moxidectin still survived to adulthood. Our findings confirm that using black soldier fly larvae is a promising technology for recycling organic wastes, including those of plant origin.     

Effects of aeration rate and feed on growth,productivity and nutrient composition of black soldier fly (Hermetia illucens L.) larvae

Black soldier fly larvae (Hermetia illucens L.) are widely cultivated as bioconversion agents. These larvae are known to be highly sensitive to changes in the external environment, such as temperature and relative humidity. Therefore, a rearing hive equipped with an instrumentation system known as the Modular Fly Hive was designed to cultivate black soldier larvae. This study aimed to determine the effects of aeration rate (0 – 0.84 m³/s.) and feed type (coconut endosperm waste and soybean curd) on growth and productivity of black soldier fly cultivated in Modular Fly Hives as well as well as feed digestibility and nutrient composition of the larval biomass. Increasing aeration rate decreased the average temperature and relative humidity within the hives. The results showed that the larvae demonstrated a sigmoidal growth curve for all types of feed and the type of feed significantly affects the average wet weight and length of the larvae. The greatest dry biomass productivity (52.85 ± 3.85 g/m²/day) was observed when the larvae were cultivated using soybean curd residue with an aeration rate of 0.84 m³/s, while the lowest dry biomass productivity (35.27 ± 9.72 g/m²/day) was observed when the larvae were cultivated using coconut endosperm waste without aeration. Proximate analysis revealed that the larval biomass had total protein, lipid, ash and carbohydrate content in the range of 37.20 – 48.60%, 9.61 – 20.02%, 4.80 – 6.40%, 33.86 – 38.70%, respectively. Amino acid in the biomass were dominated by glutamic acid (11.11–12.30%), aspartic acid (8.25 – 10.35%), leucine (8.09 – 8.57%), and lysine (6.74 – 8.14%). Lipid isolated from the larval biomass were mainly composed of lauric acid (28.35–61.68%), linoleic acid (6.27 – 30.29%), palmitic acid (7.62 – 15.23%), and myristic acid (5.05 – 14.34%).     

黑水虻幼虫处理餐厨垃圾过程中体内养分组成与消化酶活性变化规律的研究

黑水虻Hermetia illucens作为一种新型资源环境昆虫,其幼虫可以处理餐厨垃圾、畜禽粪便、蔬菜残体等各种有机废弃物。幼虫富含蛋白质和油脂,可以作为水产饲料的蛋白来源。本研究探索黑水虻幼虫处理餐厨垃圾过程中其养分组成与消化酶活性变化之间的关系。通过黑水虻幼虫自由取食餐厨垃圾,每日采集样品用于物质养分和消化酶活性的测定。结果显示：黑水虻幼虫粗蛋白含量呈现先下降后上升的变化规律,而幼虫总糖含量呈现先上升后下降的变化规律,粗脂肪含量维持上升的趋势。幼虫处理餐厨垃圾过程中,体内蛋白酶在初期迅速上升,第6天后逐渐下降,而淀粉酶呈现出先缓慢上升再迅速上升最后下降的变化规律。脂肪酶在黑水虻幼虫处理餐厨垃圾前期保持较高的活性然后缓慢下降。同时,通过相关性分析,黑水虻幼虫粗蛋白含量变化与蛋白酶活性没有相关性,而总糖与粗脂肪含量变化分别与淀粉酶、脂肪酶有相关性。因此,部分消化酶活性变化与黑水虻幼虫养分组成具有一定的联系,本研究结果为工厂化养殖黑水虻提供一定的理论基础。     

进境小麦下脚料养殖黑水虻幼虫的饲料配比研究

黑水虻Hermetia illucens是一种备受关注的资源昆虫,主要用于处理粪便和餐厨余垃圾,虫体也可作为蛋白源进入下游的牲畜饲料。本研究以黑水虻幼虫为试验对象,设置5个不同配比的黑水虻饲料配方,探究进境小麦下脚料用于黑水虻饲养的可行性。研究发现,黑水虻幼虫抗逆性极好,不同饲料配方饲养的黑水虻幼虫存活率均超过95%。幼虫干虫的营养成分分析表明,进境小麦下脚料所养殖的幼虫蛋白成分可达45%,油脂含量可达30%,比常规蛋白饲料豆粕的44.2%蛋白含量稍高。综合黑水虻幼虫鲜重、干重、干重率以及饲料降解量的养殖结果,小麦下脚料含量为60%的饲料配方具有最佳的转化产出。     

Improvement in bioconversion efficiency and reduction of ammonia emission by introduction of fruit fermentation broth in a black soldier fly larvae and kitchen waste conversion system

The black soldier fly (BSF), Hermetia illucens (Diptera: Stratiomyidae), is an insect commonly used for the bioconversion of various organic wastes. Not only can the BSF convert organic waste into macromolecular organic substances, such as insect proteins, but it can also lessen the pollution associated with these waste products by reducing ammonia emissions, for example. In this study, we measured the effects of adding fruit fermentation broth (Fer) and commercial lactic acid bacteria fermentation broth (Em) to kitchen waste (KW), as deodorizing auxiliary substances, on the growth performance of black soldier fly larvae (BSFL), the intestinal flora structure of BSFL, the ammonia emission from the KW substrate, and the microbial community structure of the KW substrate. We found that the addition of Fer or Em increased the body weight of BSFL after 6 d of culture, increasing the growth rate by 9.96% and 7.96%, respectively. The addition of Fer not only reduced the pH of the KW substrate but also increased the relative abundance of probiotics, such as Lactobacillus, Lysinibacillus, and Vagococcus, which inhibited the growth of ammonifiers such as Bacillus, Oligella, Paenalcaligenes, Paenibacillus, Pseudogracilibacillus, and Pseudomonas, resulting in the reduction of ammonia emission in the KW substrate. Moreover, the addition of Fer or Em significantly increased the relative abundances of Bacteroides, Campylobacter, Dysgonomonas, Enterococcus, and Ignatzschineria in the gut of BSFL and increased the species diversity and richness in the KW substrate. Our findings provide a novel way to improve the conversion rate of organic waste and reduce the environmental pollution caused by BSF.     

Nutritional composition of black soldier fly larvae feeding on agro-industrial by-products

Black soldier fly (BSF) larvae, Hermetia illucens L. (Diptera: Stratiomyidae), bio-convert organic side streams into high-quality biomass, the composition of which largely depends on the side stream used. In the present study, BSF larvae were reared on feed substrates composed of dried brewers’ spent grains, each supplemented with either water, waste brewer’s yeast, or a mixture of waste brewer’s yeast and cane molasses to obtain 12 different substrates: barley/water, barley/yeast, barley/yeast/molasses, malted barley/water, malted barley/yeast, malted barley/yeast/molasses, malted corn/water, malted corn/yeast, malted corn/yeast/molasses, sorghum-barley/water, sorghum-barley/yeast, and sorghum-barley/yeast/molasses. The crude protein, fat, ash, and mineral contents of the BSF larvae fed each feed substrate were quantified by chemical analyses. The effect of substrate, supplementation, and their interaction on crude protein, fat, and ash contents of BSF larval body composition was significant. Calcium, phosphorus, and potassium were the most abundant macrominerals in the larvae and their concentrations differed significantly among substrates. These findings provide important information to support the use of BSF larval meal as potential new source of nutrient-rich and sustainable animal feed ingredients to substitute expensive and scarce protein sources such as fishmeal and soya bean meal.     

Biochemical characterization of digestive enzymes in the black soldier fly,Hermetia illucens (Diptera: Stratiomyidae)

The black soldier fly, Hermetia illucens, is beneficial because its larvae feed on organic materials derived from plants, animals and humans and promote the recycling of food waste and organic materials. We investigated the biochemical properties of digestive enzymes released from the salivary gland and gut of the black soldier fly. Because the gut extracts of the black soldier fly larvae had high amylase, lipase and protease activities, we suggested that the black soldier fly might belong to the polyphagous insect group. In addition, a strong trypsin-like protease activity was observed in the gut extracts of the black soldier fly larvae. Higher activities of leucine arylamidase, α-galactosidase, β-galactosidase, α-mannosidase and α-fucosidase were observed from the gut extracts of the black soldier fly larvae compared with those of house fly larvae. These findings may explain previous reports that the black soldier fly larvae can digest food wastes and organic materials more efficiently than any other known species of fly.     

黑水虻幼虫和预蛹的饲料价值研究进展

黑水虻Hermetia illucens L.是一种全世界广泛分布的资源昆虫,幼虫在自然界以动物粪便、腐烂的有机物,如腐肉、腐烂的水果、蔬菜和植物性垃圾为食,能够被用于畜禽粪便的无害化处理。黑水虻幼虫在将粪便转化成昆虫生物量的同时,减少了粪便的污染。利用畜禽粪便饲养的黑水虻幼虫干重达到42%～43%,其中粗蛋白含量占干重的42%～44%,脂肪含量占干重的31%～35%,灰份占干重的11%～15%,钙质占干重的4.8%～5.1%,磷占干重的0.60%～0.63%。使用粪便饲养的幼虫和预蛹,含有丰富的必需氨基酸和矿物质,是家禽、家畜和鱼类养殖的良好饲料来源。文章综述利用不同动物粪便饲养的黑水虻幼虫和预蛹的饲料价值及其幼虫和预蛹用于鸡、猪和鱼类饲料添加剂的研究进展。     

Black soldier fly (Diptera: Stratiomyidae) larval heat generation and management

Mass production of black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), larvae results in massive heat generation, which impacts facility management, waste conversion, and larval production. We tested daily substrate temperatures with different population densities (i.e., 0, 500, 1000, 5000, and 10 000 larvae/pan), different population sizes (i.e., 166, 1000, and 10 000 larvae at a fixed feed ratio) and air temperatures (i.e., 20 and 30 °C) on various production parameters. Impacts of shifting larvae from 30 to 20 °C on either day 9 or 11 were also determined. Larval activity increased substrate temperatures significantly (i.e., at least 10 °C above air temperatures). Low air temperature favored growth with the higher population sizes while high temperature favored growth with low population sizes. The greatest average individual larval weights (e.g., 0.126 and 0.124 g) and feed conversion ratios (e.g., 1.92 and 2.08 g/g) were recorded for either 10 000 larvae reared at 20 °C or 100 larvae reared at 30 °C. Shifting temperatures from high (30 °C) to low (20 °C) in between (∼10-d-old larvae) impacted larval production weights (16% increases) and feed conversion ratios (increased 14%). Facilities should consider the impact of larval density, population size, and air temperature during black soldier fly mass production as these factors impact overall larval production.     

Using black soldier fly larvae for processing organic leachates

A large number of biodegradable byproducts including alcohols, soluble saccharides, volatile organic acids, and amines accumulate in the liquid fraction (leachate) produced as vegetal and food scrap waste decomposes. Untreated leachate, because it is rich in nutrients and organic byproducts, has a high chemical oxygen demand and is normally cleared of soluble organic byproducts by mineralization before its discharge into waterways. Mineralizing leachates using chemical and microbial biotechnologies is, however, a lengthy and costly process. We report here that the larvae of the black soldier fly Hermetia illucens (L.) (Diptera: Stratiomyidae), an insect rich in protein and lipids, and having significant commercial value, while feeding and growing off of compost leachate, lowers its chemical oxygen demand relative to that of leachate unexposed to larvae, neutralizes its acidity, and clears it of volatile organic acids, amines, and alcohols. These observations demonstrate that black soldier fly larvae could be used to help offset the cost and clean up of organic solutes in leachate waste streams while recycling carbon, nitrogen, and phosphate into usable and commercially valuable biomass.     

Characteristics and nutrient function of intestinal bacterial communities in black soldier fly (Hermetia illucens L.) larvae in livestock manure conversion

The potential utility of black soldier fly larvae (BSFL) to convert animal waste into harvested protein or lipid sources for feeding animal or producing biodiesel provides a new strategy for agricultural waste management. In this study, the taxonomic structure and potential metabolic and nutrient functions of the intestinal bacterial communities of BSFL were investigated in chicken and swine manure conversion systems. Proteobacteria, Firmicutes and Bacteroidetes were the dominant phyla in the BSFL gut in both the swine and chicken manure systems. After the larvae were fed manure, the proportion of Proteobacteria in their gut significantly decreased, while that of Bacteroidetes remarkably increased. Compared with the original intestinal bacterial community, approximately 90 and 109 new genera were observed in the BSFL gut during chicken and swine manure conversion, and at least half of the initial intestinal genera found remained in the gut during manure conversion. This result may be due to the presence of specialized crypts or paunches that promote microbial persistence and bacteria–host interactions. Ten core genera were found in all 21 samples, and the top three phyla among all of the communities in terms of relative abundance were Proteobacteria, Firmicutes and Bacteroidetes. The nutrient elements (OM, TN, TP, TK and CF) of manure may partly affect the succession of gut bacterial communities with one another, while TN and CF are strongly positively correlated with the relative abundance of Providencia. Some bacterial taxa with the reported ability to synthesize amino acids, Rhizobiales, Burkholderia, Bacteroidales, etc., were also observed in the BSFL gut. Functional analysis based on genes showed that intestinal microbes potentially contribute to the nutrition of BSFL and the high-level amino acid metabolism may partly explain the biological mechanisms of protein accumulation in the BSFL body. These results are helpful in understanding the biological mechanisms of high-efficiency nutrient conversion in BSFL associated with intestinal microbes.     

Bioconversion of poultry manure and vegetable waste mixes by Hermetia illucens (Diptera: Stratiomyidae)

Development time, survival and final nutrient content of Hermetia illucens L. larvae depends on the substrates in which they develop. Mixing different waste types together can increase the performance and survival of the larvae, as well as their waste reduction. The main objective of this study was to evaluate the effect of different ratios of mixed fruit and vegetable waste with poultry manure on larval development time, size, biomass production, survival, bioconversion and waste reduction. Freshly hatched neonates (90 mg; approx. 6000 individuals) were placed on 12 kg of a mixture of fruit and vegetable waste and fresh, unprocessed poultry manure and held at 28 ± 0.5°C. Inclusion of fruit and vegetable waste varied from 0% to 100% in 10% increments. Initial temperature of the substrate was also measured. The individual mass of larvae increased significantly as more fruit and vegetable waste was included, from less than 81.3 ± 6.6 mg on poultry manure only to an average size of 211.6 ± 6.0 mg at 100% fruit and vegetable waste. After approximately 60% inclusion of fruit and vegetable waste the performance and survival of the larvae increased significantly while development time was reduced. A combination of high fruit and vegetable waste and low initial temperatures resulted in lower development time overall. The mixing of wastes can be applied in industry to further the goals of waste reduction and biomass production while incorporating low-quality wastes like poultry manure.     

Isolation of Hermetia illucens larvae core gut microbiota by two different cultivation strategies

Hermetia illucens larvae (black soldier fly larvae, BSFL) convert efficiently organic waste to high quality biomass. To gain knowledge on the specific functions of gut microbes in this process it is a prerequisite to culture members of the core gut microbiota. Two different cultivation strategies were applied here for this purpose, a dilution-to-extinction cultivation and direct plating using six different media to culture aerobic heterotrophic bacteria. A total of 341 isolates were obtained by the dilution-to-extinction cultivation and 138 isolates by direct plating from guts of BSFL reared on chicken feed. Bacterial isolates were phylogenetically identified at the genus level by 16S rRNA gene sequencing (phylotyping) and differentiated at the strain level by genomic fingerprinting (genotyping). The main proportion of isolates was assigned to Proteobacteria, Firmicutes (Bacilli), and Actinobacteria. Predominant genera discussed in literature as member of a potential BSFL core gut microbiota, Providencia, Proteus, Morganella, Enterococcus, Bacillus, and members of the family Enterobacteriaceae, were isolated. A high intra-phylotype diversity was obtained by genomic fingerprinting which was especially enhanced by the dilution-to-extinction cultivation. This study showed that the application of different cultivation strategies including a dilution-to-extinction cultivation helps to culture a higher diversity of the BSFL gut microbiota and that genomic fingerprinting gives a better picture on the genetic diversity of cultured bacteria which cannot be covered by a 16S rRNA gene sequence based identification alone.

     

Inoculating poultry manure with companion bacteria influences growth and development of black soldier fly (Diptera: Stratiomyidae) larvae

The growth and development of black soldier fly, Hermetia illucens (L.), larvae fed chicken manure inoculated with bacteria isolated from black soldier fly larvae and associated larval feed was evaluated. Four strains of Bacillus subtilis were evaluated. B. subtilis strains S15, S16, S19, were isolated from the gut of black soldier fly larvae. B. natto strain D1 was isolated from the diet fed to black soldier fly larvae. These bacteria were added individually into nonsterile 200 g fresh hen manure at 10(6) cfu/g and homogenized. Treated manure was then inoculated with 4-d old black soldier fly larvae. Prepupal weight ranged from 0.0606 g in the control to 0.0946 g in manure treated with the S15 strain. Larval survivorship to the prepupal stage in all treatments ranged from 98.00 ± 2.65% to 99.33 ± 1.15%. Prepupal survivorship to the pupal stage ranged from 91.92 ± 1.87% to 97.95 ± 1.03%. Adult emergence from the pupal stage did not significantly (P < 0.05) differ across treatments and ranged from 98.95 ± 1.82% to 100.00 ± 0.00%. Adult body length resulting from the larvae in each of the treatments was significantly greater than those from the control. Longevity of adults did not differ significantly between treatments. Time from hatching to the development of the first pupa did not differ significantly across treatments; however, development time from hatching to 90% reaching the prepupual stage was significantly different between treatments and ranged from 29.00 ± 1.00 d to 34.33 ± 3.51 d. Development time from hatching to 90% reaching the adult stages was significantly different between treatments. Our results demonstrate that inoculating poultry manure with bacteria from black soldier fly larvae influences the growth and development of conspecific larvae feeding on the manure.     

Development of black soldier fly (Diptera: Stratiomyidae) larvae fed dairy manure

Black soldier flies, Hermetia illucens L., are a common colonizer of animal wastes. However, all published development data for this species are from studies using artificial diets. This study represents the first examining black soldier fly development on animal wastes. Additionally, this study examined the ability of black soldier fly larvae to reduce dry matter and associated nutrients in manure. Black soldier fly larvae were fed four rates of dairy manure to determine their effects on larval and adult life history traits. Feed rate affected larval and adult development. Those fed less ration daily weighed less than those fed a greater ration. Additionally, larvae provided the least amount of dairy manure took longer to develop to the prepupal stage; however, they needed less time to reach the adult stage. Adults resulting from larvae provided 27 g dairy manure/d lived 3-4 d less than those fed 70 g dairy manure. Percentage survivorship to the prepupal or adult stages did not differ across treatments. Larvae fed 27 g dairy manure daily reduced manure dry matter mass by 58%, whereas those fed 70 g daily reduced dry matter 33%. Black soldier fly larvae were able to reduce available P by 61-70% and N by 30-50% across treatments. Based on results from this study, the black soldier fly could be used to reduce wastes and associated nutrients in confined bovine facilities.     

非水虻源微生物与武汉亮斑水虻幼虫联合转化鸡粪的研究

【目的】益生微生物在协助亮斑扁角水虻幼虫转化有机废弃物、提高其转化效率方面具有重要的作用,本研究针对非水虻源微生物,开展与水虻联合转化鸡粪的研究,以阐明外源微生物在水虻转化畜禽粪便中的作用,对其转化机制的研究及产业化生产具有重要意义。【方法】采用稀释涂平板的方法进行鸡粪堆肥和猪粪堆肥中细菌的分析,并将筛选到的细菌分别接种到无菌的鸡粪基质中与武汉亮斑水虻幼虫联合转化,通过称重法测定转化后武汉亮斑水虻及鸡粪的重量,评价转化效果及对幼虫的影响,然后将促进转化效果明显的菌株按不同比例进行复配,与武汉亮斑水虻幼虫联合转化新鲜鸡粪,分析复配菌剂对武汉亮斑水虻幼虫转化鸡粪的影响。【结果】结果显示R-07、R-09、F-03和F-06在促进武汉亮斑水虻幼虫生长和鸡粪转化的效果上最为显著。与对照组相比,水虻幼虫转化率分别提高了27.21%、15.00%、9.93%和16.29%;基质减少率分别提高了17.94%、10.42%、7.84%和9.27%。将这4株细菌配制复配菌剂与武汉亮斑水虻幼虫联合转化鸡粪,结果显示复配比例为R-07:R-09:F-03:F-06=4:1:1:1时效果最好,与空白对照相比,武汉亮斑水虻幼虫存活率提高了10.25%,幼虫虫重增加了28.41%,幼虫转化率增加了30.46%,鸡粪减少率增加了7.69%。【结论】添加通过筛选优化的非水虻来源的微生物复合菌剂能够促进水虻高效转化鸡粪,研究结果有助于改善现有的武汉亮斑水虻幼虫转化体系,为开发新型的联合转化工艺、更加有效地处理畜禽粪便奠定基础。     

The potential of soil amendment with insect exuviae and frass to control the cabbage root fly

Reliable options to control the cabbage root fly, Delia radicum L., are lacking in many countries as restrictions on insecticide use have tightened due to environmental concerns. Although microbial control agents are often considered as a sustainable alternative, their application in agriculture is constrained by inconsistent efficacy owing to low field persistence. To stimulate naturally occurring beneficial microbes, soil amendment with the residual streams of insect production has been suggested as an alternative to synthetic fertilization and a new approach to microbial crop protection. In a set of greenhouse experiments, exuviae and frass of black soldier fly larvae, Hermetia illucens L., house crickets, Acheta domesticus L. and exuviae of mealworms, Tenebrio molitor L., were added to soil from an organically managed field. Exuviae and frass treatments were compared to treatments with synthetic fertilizer. Brussels sprouts, Brassica oleracea L., plants were grown in amended soil for 5 weeks before being infested with cabbage root fly larvae. Insect and plant performance were assessed by recording cabbage root fly survival, biomass and eclosion time and seed germination and plant biomass, respectively. Whereas soil amendment with black soldier fly frass or exuviae reduced cabbage root fly survival and biomass, respectively, amendment with house cricket or mealworm residual streams did not negatively affect root fly performance. Furthermore, seed germination was reduced in soil amended with house cricket exuviae, while amendment with either residual stream derived from black soldier fly larvae or house crickets resulted in lower plant shoot biomass compared with the synthetic fertilizer treatment. Amending soil with black soldier fly residual streams could become a novel and low-cost tool to be integrated in cabbage root fly management programmes, especially where methods currently available are insufficient. Therefore, the mechanisms underlying the effects of insect-derived soil amendments described here should be the focus of future research.     

肠道共生细菌预发酵鸡粪对黑水虻生长发育的影响

以利用黑水虻Hermetia illucens L.肠道共生细菌不同菌株培养液预发酵的鸡粪为培养料,研究了添加不同菌株的发酵鸡粪对黑水虻幼虫生长发育的影响。结果表明,添加不同菌株的预发酵鸡粪能显著增加预蛹和蛹的重量,显著提高化蛹率并增加雌、雄成虫体长,缩短预蛹所需时间,但对幼虫存活率、成虫羽化率、成虫寿命没有显著影响。同时,不同菌株的作用效果有所不同。