In situ nitrogen mineralization and nutrient release by soil amended with black soldier fly frass fertilizer

Abstract

Although black soldier fly frass fertilizer (BSFFF) is effective on crop performance, information on nitrogen (N) mineralization and nutrient release capacity of soils amended with BSFFF is lacking. This study utilized field incubation experiments to investigate the ammonification, nitrification, microbial populations, and quantities of nutrients released by soils amended with BSFFF and commercial organic fertilizer (SAFI) for a period equivalent to two maize cropping seasons. For the control treatment, no BSFFF or SAFI was added. Results indicated that most of the N in BSFFF amended soils was available in the ammonium form, while soils treated with SAFI had higher nitrate concentration. The BSFFF amended soils experienced shorter net immobilization periods of N (30–60 days) compared to SAFI treated soils (60–95 days). Increased rates of mineralization (3–10 times) and nitrification (2–4 times) were observed in soils treated with BSFFF during the second season of application. The BSFFF treated soils showed significantly higher N, phosphorus, and magnesium release than the control. Repeated application of BSFFF led to increased N release by three-folds in the soil. Furthermore, soil amendment with BSFFF increased the populations of bacteria and fungi, reduced soil acidity, and increased phosphorus (two-folds) and magnesium (two–four-folds) release than SAFI treated soils. Our findings highlight the crucial role of BSFFF in improving soil health by addressing the challenges of soil acidity, phosphorus fixation and nutrient mining, which is characteristic of most tropical soils.

Evolving dynamics of insect frass fertilizer for sustainable nematode management and potato production

“…The significant improvements in the soil chemical properties observed during the study demonstrate the capability of the BSCOF and pupal exuviae chitin to boost soil fertility and create a favorable environment for crop performance. The increase in soil pH observed in this study has been previously reported (Beesigamukama et al, 2021;Menino et al, 2021). Our findings indicates the ability of the BSCOF and chitin-fortified BSFCOF in alleviating soil acidity which is a key challenge to crop production in sub-Saharan Africa (Tully et al, 2015;Montanarella et al, 2016).…”

Nutrient quality and maturity status of frass fertilizer from nine edible insects

“…For example, previous studies have reported higher yields and nutritional quality of maize, tomatoes, kales, French beans, cow peas, chilli pepper, shallots and barley grown using H. illucens frass fertilizer and meal worm frass fertilizer compared to conventional fertilizers 27 , 28 , 42 , 52 , 53 . Furthermore, soil amendment with frass fertilizer from H. illucens and T. molitor was found to suppress soil borne pathogens, stimulate soil microbial activity, reduce soil acidity and salinity, improve nitrogen mineralization, and increase availability of nutrients in the soil 29 – 31 , 33 , 53 , thus improving the soil quality for plant growth. It is therefore anticipated that adoption of insect fertilizer would contribute to improving food security by in SSA reversing the worrying trends in soil degradation, nutrient mining and declining crop productivity 1 , 8 , 14 .…”

Waste to value: Global perspective on the impact of entomocomposting on environmental health, greenhouse gas mitigation and soil bioremediation

“…Assessment of frass C/N ratio has shown that BSFL composting can significantly reduce the C/N ratio to values recommended for field application (〈12). The low C/N ratio of BSF frass is critical for ensuring higher nutrient mineralization and better synchrony for plant uptake ( Beesigamukama et al, 2020c , Beesigamukama et al, 2021c ; Adin Yéton et al, 2019 ).…”

“…6 ). Entomocompost is superior to compost and synthetic fertilizers in boosting populations of beneficial soil microbiota, reducing soil acidity, increasing nutrient availability for plant uptake ( Beesigamukama et al, 2020a , Beesigamukama et al, 2020c , Beesigamukama et al, 2021c ; Rummel et al, 2021 ). Moreover, soil amendment with 2–8 % of BSF frass fertilizer has been found to cause remarkable improvement in pH, organic matter, macronutrients, and fixation of heavy metals such as cadmium and lead by 8–57 % and 22–166 %, respectively ( Wang et al, 2022 ).…”