Arbuscular mycorrhizal fungi and proximal sensing for improving nutrient use efficiencies in wheat (Triticum aestivum L.)

Abstract

A 4 years field study was conducted to improve nitrogen (N) and phosphorus (P) use efficiencies in wheat (Triticum aestivum L.) using arbuscular mycorrhizal fungi (AMF) and precision N management. Split plot design was employed to rationalize N and P fertilizer use in two different experiments with AMF in the main plot and fertilizer application practice in the subplots. The AMF seed coating improved mycorrhization, root dry weight and P uptake. AMF coating of wheat seeds improved mean grain yield and agronomic efficiency of applied P fertilizer (AE_P) by 11% and 55.4%, respectively. However, AMF seed coating did not improve chlorophyll content, normalized difference vegetative index, grain yield and agronomic efficiency of applied N fertilizer (AE_N). Precision N management using leaf color chart (LCC), chlorophyll meter (SPAD), and GreenSeeker optical sensor (GS) sustained wheat grain yield equivalent to the soil-test based N fertilizer recommendation with 20–31 kg ha⁻¹ less fertilizer N. Proximal sensing guided N use improved AE_N by 21.9%–39.6% while mitigating global warming potential by 16%–24%. Integrated use of AMF seed coating and precision N management provides a potential solution to improve N and P nutrition and reduce environmental footprints of fertilizer N use in wheat.

Keywords:

• Mycorrhiza
• nitrogen
• phosphorus
• precision management

Disclosure statement

No conflict of interest was reported by the authors.

Additional information

Funding

The authors acknowledge the TERI (The Energy and Resources Institute), New Delhi, India, for providing financial assistance and AMF to carry out this study.