Black soldier fly frass: a new organic fertilizer or biostimulant?

Fecha de publicación: 09/06/2024
Fuente: ISHS (International Society for Horticultural Science)
Post date: Sunday 9 June 2024
Author:
ISHS Secretariat

To feed an estimated population of 9.7 billion by 2050, food production needs to increase significantly while protecting the environment and minimizing food waste. One promising approach lies in organic alternatives to chemical fertilizers and pesticides. Through the farming of insects, organic waste is bioconverted into larval biomass to be used as livestock feed, but the process also generates a new source of organic waste in the form of exuviae and frass, which can be used as crop fertilizers. We hypothesized that the type of diet, processing method, and application rate will influence the effects of black soldier fly (Hermetia illucens (L.)) frass (BSFF) on plant growth and substrate properties. To test this hypothesis, we conducted a greenhouse experiment at Université Laval in Quebec, Canada, using six different BSFF made with one of two diets (fruit/vegetable/bakery waste (FVBB) or standard Gainsville diet (GV)) and having undergone one of three processing treatments (no treatment, dehydration, or pasteurization). BSFF was applied at five rates (0, 125, 250, 375, and 500 mg of nitrogen L-1) to tomato (M82) plants, which were cultivated for four weeks. During this time, plant growth, photosynthesis, and growing media parameters were measured. The plants were then harvested for fresh and dry weight measurements. Our study revealed that FVBB frass was superior to GV frass in promoting plant growth and enhancing photosynthesis parameters. This implies that the FVBB frass may be a better source of essential nutrients and may contain compounds or microbial communities that further stimulate plant growth (biostimulants). Processing methods exerted a relatively minor influence on the FVBB diet compared to the GV diet. Finally, higher application rates of frass from both diets correlated with improved plant performance.
Robab Mahmoudi won the ISHS Young Minds Award for the best oral presentation at the IV International Symposium on Organic Greenhouse Horticulture in Mexico in October 2023.
Robab Mahmoudi, Centre de recherche et d’innovation sur les végétaux (CRIV), Département de phytologie (FSAA), Université Laval, Pavillion Envirotron, Québec, QC G1V 0A6, Canada, e-mail: robab.mahmoudi.1@ulaval.ca
The article is available in Chronica HorticulturaeTags: fertilizerbiostimulantblack soldier fly frassCategories: Young Minds Award Winners