Hermetia illucens frass improves the physiological state of basil (Ocimum basilicum L.) and its nutritional value under drought

Abstract

To counterbalance the growing human population and its increasing demands from the ecosystem, and the impacts on it, new strategies are needed. Use of organic fertilizers boosted the agricultural production, but further increased the ecological burden posed by this indispensable activity. One possible solution to this conundrum is the development and application of more environmentally neutral biofertilizers. The aim of this study was to compare the effectiveness of two doses of Hermetia illucens frass (HI frass) with the commercial cattle manure in the cultivation of basil under drought. Soil without the addition of any organic fertilizer was used as a baseline control substrate for basil cultivation. Plants were grown with cattle manure (10 g/L of the pot volume) or HI frass at two doses (10 and 12.5 g/L). The health and physiological condition of plants were assessed based on the photosynthetic activity and the efficiency of photosystem II (chlorophyll fluorescence). Gas exchange between soil and the atmosphere were also assessed to verify the effect of fertilizer on soil condition. In addition, the mineral profile of basil and its antioxidant activity were assessed, along with the determination of the main polyphenolic compounds content. Biofertilizers improved the fresh mass yield and physiological condition of plants, both under optimal watering and drought, in comparison with the non-fertilized controls. Use of cattle manure in both water regimes resulted in a comparably lower yield and a stronger physiological response to drought. As a result, using HI frass is a superior strategy to boost output and reduce the effects of drought on basil production.

Insect-based agri-food waste valorization: Agricultural applications and roles of insect gut microbiota

“…The application of insect frass as fertilizer has also been shown to improve plant tolerance to stress and enhance plant quality. In comparison to cattle manure, BSF frass was determined to be more effective in promoting basil plant growth and mitigating the effects of drought, leading to an improvement in plant quality [ 84 ]. Similarly, using BSF frass as an organic fertilizer has been demonstrated to reduce salinity stress and enhance lettuce quality.…”

Hermetia illucens Frass Fertilization: A Novel Approach for Enhancing Lettuce Resilience and Photosynthetic Efficiency under Drought Stress Conditions

“…Freeze-dried plant samples were subjected to mineralization according to the innovative method described previously [54]. It involved the use of a high-pressure/hightemperature system using microwave energy.…”