Vnt4, a derived formulation of glutacetine® biostimulant, improved yield and n-related traits of bread wheat when mixed with urea-ammonium-nitrate solution

Abstract

Optimizing nitrogen use efficiency (NUE) could mitigate the adverse effects of nitrogen (N) fertilizers by limiting their environmental risks and raising agronomic performance. We studied the effects of VNT4, a derived formulation of Glutacetine® biostimulant, mixed with urea-ammonium-nitrate solution (UAN) on the growth, N-related traits and agronomic performance of winter wheat (Triticum aestivum L.). The experiment was performed under six contrasting field conditions over two years in Normandy (France), including a site where15N labelling was undertaken. Taking into account all the sites, we report that VNT4 significantly improved grain yield (+359 kg ha−1), total grain N and NUE. VNT4 application improved growth during tillering and stem elongation (+10.7%), and N and15N uptake between tillering and maturity (+7.3% N and +16.9%15N) leading to a higher N accumulation at maturity (+9.3% N). This N mainly originated from fertilizer (+19.4%15N) and was assimilated after the flag leaf stage in particular (+47.6%15N). These effects could be related to maintenance of physiological functions of flag leaves as suggested by the enhancement of their nutrient status (especially S, Zn and Mo). The adoption of VNT4 as a UAN additive is an efficient agronomic practice to enhance wheat productivity under an oceanic temperate climate.