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

PLoS One. 2023 Jan 17;18(1):e0280037. doi: 10.1371/journal.pone.0280037. eCollection 2023.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Diptera*
  • Droughts
  • Ecosystem
  • Fertilizers
  • Humans
  • Manure
  • Nutritive Value
  • Ocimum basilicum* / chemistry
  • Soil / chemistry

Substances

  • Fertilizers
  • Manure
  • Soil

Grants and funding

This work was supported by several funding sources, such as the Narodowe Centrum Badań i Rozwoju (grant no. POIR.01.01.01-00-1503/19, entitled Development of a technology for the production of organic fertilizer (in the form of pellets/granules) based on the Hermetia illucens frass and testing its impact on selected plants. Funding for open access to this research was provided by University of Tennessee’s Open Publishing Support Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.