Compost tea and bioslurry as plant biostimulants. Part 2: biofertilizer test in ornamental flowers

Abstract

The present study tested the effect of aerated (AM), non-aerated (NAM), a 1:1 combination of both compost teas (A-NAM), and bioslurry (B) as bio-fertilizers in two ornamental plants growing in different substrates. The present study aimed to evaluate the products as biostimulants in ornamental plants. Compost teas were brewed from a composted mixture of residues, while bioslurry was prepared, with fresh material and no aeration. Two ornamental plant species were used: Petunia hybrida and Impatiens walleriana. Experimental presented a completely randomized factorial design, with two factors: Biostimulants with 6 levels: AM, NAM, A-NAM, B, F (traditional fertilizer), and H₂O (control); and Substrate, with 3 levels: sand, commercial, and compost. Bio-inputs presented variable properties and effects on plant growth, with significant interaction between factors. In sand, no effect of bioproducts on plant biomass, SPAD index and pigments content were observed. In compost, B significantly increased I. walleriana and P. hybrida dry biomass (1.75 ± 0.42 g and 1.54 ± 0.28 g, respect to 1.33 ± 0.18 g for H₂O), while in the commercial substrate, only in P. hybrida (1.35 ± 0.44 g, regarding 0.42 ± 0.11 g for H₂O). All bio-inputs increased pigments content of both plant species in all substrates. To our knowledge, this is the first record that B was tested, which increased plant biomass at similar values to traditional fertilizer. We demonstrated that the biostimulants brewed from organic residues might present the same performance as commercial fertilizers.

Keywords:

• Biofertilizers
• compost extract
• nutrients
• Impatiens walleriana
• Petunia hybrida

Acknowledgements

The authors are especially thankful to Gastón Alfredo Pinter for figures design assistance.

Disclosure statement

No potential conflict of interest was reported by the authors.

Availability of data and materials

All data generated and analyzed during this study are included in this published article as ‘public_data.xlsx’ archive in the preprinted document DOI: 10.21203/rs.3.rs-56311/v1.

Authors contribution

The authors declare that they have no competing interests. IFP supervise and design greenhouse experiments, performed toxicology test, determined pigments content, organized and statistically analyzed all data, and write manuscript; GP designed and guide greenhouse experiments; MA collected greenhouse and microorganism data; and MU directed and supervise all experimental and publication process. All authors read and approved the final manuscript.

Additional information

Funding

This work was supported by the Fondo para la Investigación Científica y Tecnológica under Grant PICT 2015-1727 to Ernesto Martín Uliarte and PICT 2019-2193 to Iván Funes Pinter; and the Agroecology Network of INTA (REDAE) and the North Oasis Territorial Project (PRET) of INTA Mendoza; and ProyECTO inta I009 Intensificación sostenible de cultivos bajo cubierta.