“…The fertilizer solutions were prepared with analytical grade salts (Ca(NO 3 ) 2 ·4H 2 O, KH 2 PO 4 , K 2 SO 4 , MgSO 4 ·7H 2 O, (NH 4 ) 6 Mo 7 O 24 ·4H 2 O, CuSO 4 ·5H 2 O, ZnSO 4 ·H 2 O, H 3 BO 3 , MnSO 4 ·H 2 O (Panreac, Barcelona, Spain), KNO 3 (Merck & Co., Inc., Kenilworth, NJ, USA) and Fe‐EDDHA (Quimioprox, Barcelona, Spain) and had the following nutrient composition: 15, 2, 9, 10, 3 mmol L –1 of N, P, K, Ca and Mg, respectively, and 2, 1, 0.1, 4, 0.5, 0.05 mg L –1 of Fe, Mn, Cu, Zn, B, and Mo, respectively 29 . The biostimulant HUMA GRO® X‐Tend (6–2‐0, 6.02% organic matter) was provided by Bio Huma Netics, Inc. (Gilbert, AZ, USA) 30 . This product consists of a concentrated liquid produced from humic acid derivatives obtained after biological digestion of leonardite from Arizona (USA).…”