The effect of nitrogen-modified lignite granules on mycorrhization and root and shoot growth of Secale cereale (winter rye) in a nutrient-deficient, sandy soil

ABSTRACT

Organic soil amendments such as modified lignite and biostimulants like arbuscular mycorrhizal fungi (AMF) may have the potential to improve soil biological conditions of agricultural soils. The aim of the study was to test if nitrogen-modified lignite granules (NH) are beneficial for mycorrhization, root and shoot development compared to common mineral nitrogen (Nmin) in a nitrogen and phosphorus limited soil.

A greenhouse experiment with Secale cereale L. was carried out using non-sterilized and sterilized sand substrate treated with NH, AMF or Nmin and AMF+NH and AMF+Nmin and was compared to an untreated substrate (control).

7.5 t ha⁻¹ NH and 120 kg Nmin ha⁻¹ led to a similar increase of AMF colonization compared to the control; however, Nmin had a more positive influence on biomass development.

Significantly highest mycorrhizal colonization intensity was found for AMF+NH. The co-application of AMF+NH revealed that shoot and root development and shoot nutrient concentrations were significantly higher or were among the significantly highest values, when compared to the other treatments. AMF+NH may be a suitable soil amendment for nutrient-limited soils and may be more sustainable than Nmin due to a combined increase of nitrogen, AMF and carbon/humic acids in the soil that comes with the NH.

KEYWORDS:

• Arbuscular mycorrhizae
• lignite granules
• root growth
• plant biomass
• soil amendments

Acknowledgements

The assistance of Josie Engels and Anna Welsch (Brandenburg University of Technology Cottbus-Senftenberg, Chair of Soil Protection and Recultivation) with the greenhouse experiment and sampling is gratefully acknowledged. We also thank Mary T. Lavin-Zimmer, Tom Gaskin and Lydia Pohl for their comments on this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was partly funded by Novihum Technologies GmbH.