|Wednesday, November 25|
Effects of black soldier fly frass-fertilizer on the growth, yield and nitrogen use efficiency of maize in Central Kenya
* Dennis Beesigamukama, International Centre of Insect Physiology and Ecology, Kenya
Benson Mochoge, Department of Agricultural Science and Technology, Kenyatta University
Nicholas Korir, Department of Agricultural Science and Technology, Kenyatta University
Dorothy Nakimbugwe, Department of Food Technology and Nutrition, School of Food Technology, Nutrition & Bioengineeri
Komi Fiaboe, The International Institute of Tropical Agriculture (IITA)
Fathiya Khamis, International Centre of Insect Physiology and Ecology
Sevgan Subramanian, International Centre of Insect Physiology and Ecology
Martha Musyoka, International Centre of Insect Physiology and Ecology
Sunday Ekesi, International Centre of Insect Physiology and Ecology
Chrysantus Tanga, International Centre of Insect Physiology and Ecology
The black soldier fly larvae (BSF) (Hermetia illucens L.) is one of the most efficient recyclers of organic waste into quality organic fertilizer. However, no information exists on the performance of BSF frass-fertilizer on crop production. Such information is crucial for the development of commercial BSF frass-fertilizer and its integration into existing farming systems. We carried out comparative studies to evaluate the impact of BSF frass-fertilizer and commercial organic fertilizer (SAFI) applied in terms of tonnage [0, 2.5, 5 and 7.5 tonnes per hectare (t ha-1)] and nitrogen content [0, 30, 60 and 100 kg nitrogen (N) per hectare (kg N ha-1)] on maize (H513 variety) production under open field conditions. A standard mineral fertilizer treatment (Urea) [0, 30, 60 and 100 kg nitrogen (N) per hectare (kg N ha-1)] was also included. The performance of H513 maize was assessed based on the chlorophyll content, N uptake, grain yield and N use efficiency. Our results showed that application of BSF frass-fertilizers significantly increased maize grain yields compared to the other fertilizers. Plots treated with 100 kg N ha-1 BSF frass-fertilizer produced the highest maize grain yield of 5.7 t ha-1, which was 6% higher compared to that produced by equivalent rates of SAFI and Urea fertilizers. Furthermore, the application of BSF frass-fertilizer at 7.5 t ha-1 significantly increased the chlorophyll contents of H513 maize by 4 and 9% compared to SAFI and Urea fertilizers, respectively. The application of BSF frass-fertilizer at 100 kg N ha-1 also increased the N uptake by 39% compared to SAFI and 21% in relation to Urea treated plots. Maize agronomic N use efficiency in BSF frass-fertilizer treated plots was 27% and 116% higher compared to SAFI and Urea treated plots, respectively. Our findings from the study highlight that the use of appropriate BSF frass-fertilizer in maize production could optimize the response and utilization efciency of applied N, which is the most limiting nutrient to crop production in the tropics.
Effect of composted Black Soldier Fly Larvae frass on plant growth performance
* Martin Zorrilla, Nutrition Technologies Sdn Bhd, Malaysia
Zainudin Hussain, Nutrition Technologies Sdn Bhd
When Black Soldier Fly larvae (Hermetia illucens) are reared for animal feed, the raw material produced in greatest volume is not the protein or oil but the frass. Frass is considered a soil amendment, however its commercial applications and the benefits of composting the product have not been thoroughly studied. Through several field trials, Nutrition Technologies has examined the effect of an “unprocessed frass” and an “aerobically composted frass” on plant growth performance. The frass products were compared to soil amendments and fertilizers commercially available in Southeast Asia. The composted frass products resulted in improved growth performance when compared to un-processed frass. Composted frass outperformed commercially available soil amendments, while results for un-processed frass were more varied. Detailed results from several field trials involving several commercially important crops will be shared.
Progression towards circular agriculture - gaining knowledge of insect waste streams as a crop and soil health promoter
* Kirstin Torgerson, Wageningen University and Research, Netherlands
Jurian Meijering, Wageningen University and Research
Jaap Sok, Wageningen University and Research
Marcel Dicke, Wageningen University and Research
Alfons Oude Lansink, Wageningen University and Research
Insect production is gaining traction as a form of mini-livestock production. As the sector grows, more insect waste streams (IWS) (i.e. insects’ manure, molted exoskeleton, and undigested feed) accumulate. Preliminary research suggests that IWS have the potential to promote the health of crops and soil that induce a plant’s systemic resistance to pathogens and pests. In doing so, IWS could reduce, for instance, arable farmers’ usage of chemical plant protection products (e.g. pesticides such as neonicotinoids) thereby reducing their environmental consequences. Also, the use of IWS as an arable farming input aligns with the vision of circular agriculture by progressing towards closing the loop of insect production. To successfully penetrate the market as an arable farming input, farmers must first be informed of how IWS are expected to work in practice. However, such information is unknown; the objective of this research is to supply such needed information. This paper explores the Dutch farming context as the Netherlands is a driver of insect production R&D and hosts several large production facilities. Experts with knowledge of IWS and its potential application on Dutch arable farms participated in this research to determine (1) what IWS are, (2) how IWS promote the health of plants and soil, and (3) how IWS should be used in practice. Such elicited information is in accordance with Rogers’ theory regarding the knowledge required by one to progress through the innovation decision process. This research used a combination of semi-structured interviews and a 3-round Delphi study. Interviews were conducted to generate individual understandings of IWS. The results from the interviews were compared, and areas of divergence in expert opinion were identified. These areas of diverging opinion were then presented to experts in a Delphi study to determine to what extent they were able to reach an agreement. Results from the interviews were analyzed qualitatively; the Delphi study was analyzed quantitatively to calculate the Strict Agreement Index. This expert elicitation yields new insights regarding the technical mechanisms and potential applications of IWS which were previously unknown due to IWS being in the R&D phase. Such results provide a launching pad for further research in the adoption potential of IWS. The results also identify critically unanswered questions that simply cannot be addressed until more technical research on IWS’ effectiveness is performed.
In vitro antimicrobial activity of frass produced by the black soldier fly larvae against plant pathogens
* Ghazaleh Arabzadeh, Université Laval, Canada
Thi Thuy An Nguyen, Université Laval
Maxime Delisle-Houde, Université Laval
Martine Dorais, Université Laval
Marie-Hélène Deschamps , Université Laval
Nicolas Derôme , Université Laval
Russell J. Tweddell , Université Laval
Grant W. Vandenberg , Université Laval
In 2020, the control of plant diseases still relies on the use of pesticides. Negative impacts of these chemical compounds on environment and human health are now demonstrated and research for new low risk alternatives is essential. Over the past few years, it was possible to note a marked interest for the cultivation of insects as well as for the various by-products arising therefrom. In this context, an organic residue called ‘frass’ produced by the black soldier fly larvae [Hermetia illucens (Linnaeus, 1758)] was evaluated for its antimicrobial activity. The aim of this study was (1) to determine in vitro antifungal activity according to different diets (Gainesville 100%, Gainesville:VOWaste 70:30, Gainesville:VOWaste 50:50) and (2) to look for the presence of antibacterial compounds in frass solutions. Antimicrobial activity was evaluated using tryptic soy agar (TSA) medium by the double layer test for fungi and agar disc diffusion test for bacteria. For fungi, inhibition of mycelial growth (%) was determine according to reduction of mycelial diameter on TSA containing frass (0.1%) in comparison with the control (distilled sterile water). For bacteria, inhibition of bacterial growth was determined on semi-solid TSA medium by measuring the diameter of inhibition zone surrounding discs soaked with different concentrations of frass solutions previously sterilized with cold microfiltration at 0.2 micron. In both tests, horticultural plant pathogens were used. The results showed the high antifungal activity of frass solutions. Frass from larvae colonies using Gainesville 100% as a diet showed inhibition of mycelial growth >90% against all fungi tested. Both other diets tested showed inhibition growth between 30 and 85%. It would now be interesting to evaluate the possibility of spray frass solutions on horticultural crops to control plant diseases.
Search for antimicrobial molecules from lactic acid fermentation of Black Soldier Fly prepupae and related byproducts
* A.V Luparelli, Department of Food Science and Drug
The steadily growth of worlds population leads to the continuous search for new strategies to reduce and add value to organic wastes generates by the increased global agriculture production. For this purpose, a non- infesting insect, Hermetia illucens, is often used in the bio-conversion processes. The growth of this specie of insect on organic waste is a sustainable way to upgrade the nutritional value of the bio-residues. During this process, large amount of insect-derived wastes (chitinous shells and dead adult flies) and excess of larvae are also accumulated. Unlike the valorized biomass, which has a lot of applications, there is still not a sustainable way of using the insects derived wastes and the residual larvae. Recent studies are marking how the use of insects as feed are giving positive effects on the pathogens growth. At the same time, already known in literature is that fermentation help the production of antimicrobial compounds. In this work these two evidences were combined for exploring antimicrobial potential from insects wastes, using solid state fermentation with Lactic Acid Bacteria. The difference in the molecular composition between fermented and unfermented insect-derived waste materials was studied, focusing on fatty acid profiles, protein fraction and chitin. Solid state fermentation was conducted with 2 LAB strains L. Rhamnosus and L. Plantarum. Both strains had shown the highest antimicrobial activity, tested against foodborne pathogens, when they were grown on puparium. The bulk evaluation of fat, protein, moisture and ashes composition of insect-derived biomasses was carried out using standard procedures (AOAC, 2002). Then, fatty acid profiles were determined by GC-MS, whereas total amino acid quantification and total amount of chitin were simultaneously carried out by UPLC/ESI-MS methodology. The high antimicrobial activity against foodborne pathogens of the fermented substrates compared to unfermented, with a reduction of 5 Log UFC/g, suggest the formation of molecular components responsible for the antimicrobial activity. Results showed that the lipid fraction is particularly influenced by fermentation: the fermented biomass had a lower percentage of Lauric acid and Meristic acid and a higher quantity of palmitic acid and C:18 series. Also, the protein fraction seemed to change upon fermentation: it was possible to observe a redistribution of amino acids with differences related especially to different growth substrate used. Further studies are ongoing to deepen the knowledge about the molecular components responsible for the antimicrobial activity.
Biologically active components of CO2-extract of darkling beetle Alphitobius diaperinus
Nina Ushakova, A.N. Severtsov Institute of Ecology and Evolution
Efim Brodsky, A.N. Severtsov Institute of Ecology and Evolution
* Alexander Bastrakov, A.N. Severtsov Institute of Ecology and Evolution, Russian Federation
Insects attract the attention of researchers not only in connection with the developing direction of food and feed using edible insects but also with the search for new types of immunoactive, anti-infectious components of natural origin. It is relevant to study of the biochemical composition of darkling beetles (family Tenebrionidae) species, which are able to develop in a pure culture under artificial conditions. This allows using of insects as a renewable source of raw biomass. Among these species is Alphitobius diaperinus (Panzer, 1797), which has prospects for use both as an alternative protein product from larvae and for the production of biologically active compounds from an adult beetle.