Organo-mineral fertilizers can slow N release to plants, reducing N losses to the environment and enhancing N use efficiency (NUE). Yet, this greater NUE is not always coupled to greater crop yields, which warrants further investigation. Here, we assessed the relationship between N-NH
[...] Read more.
Organo-mineral fertilizers can slow N release to plants, reducing N losses to the environment and enhancing N use efficiency (NUE). Yet, this greater NUE is not always coupled to greater crop yields, which warrants further investigation. Here, we assessed the relationship between N-NH
3 losses from volatilization and wheat (
Triticum aestivum L.) biomass and N status. The following treatments were tested: conventional urea (U, 45% N), urea treated with NBPT (N-(n-butyl) thiophosphoric triamide) (U + NBPT, 45.6% N), S-coated urea (U + S; 37% N), Se-coated urea (U + Se; 45% N), organo-mineral fertilizer Azoslow 29 (OMF, 29% N + 50% Azogel
®). The above treatments and non-fertilized control were tested in two soils (LVd and LVAd, 71 and 25% clay, respectively). Semi-open static collectors were used to determine N-NH
3 volatilization 1, 2, 4, 8, 11, 15, 18, 23, 29, and 36 days after application of treatments. Wheat was cultivated for 35 days, and shoot dry mass and total leaf N were determined after harvest. Cumulative N-NH
3 losses from OMF (27 and 32% of N applied in the LVd and LVAd soils, respectively) did not differ from U and (26–32%) and U + Se (24–31%), likely due to organic matter inputs enhancing urease activity in soils. Nevertheless, OMF resulted in 2–4 times greater wheat dry matter than U, U + Se, and U + S, with similar dry mass of U + NBPT for LVAd soils. OMF application enhanced total N removal in wheat leaves relative to the unfertilized control and most N sources. N-NH
3 losses did not reduce biomass yield, but were negatively linked to N accumulation in wheat. The OMF enhanced wheat biomass and nutrition while sustaining environmental quality and promoting circularity in agroecosystems.
Full article