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The contents in carbonate-free clay-, silt-and sand-sized particle contents of the samples were determined with the pipette method after dispersion in sodium hexametaphosphate of decarbonated samples obtained by treating intact soil with a ~0.5 M HCl solution until production of CO 2 ceased. pH was determined by potentiometric measurement in a 1:2.5 w/v soil:water suspension; cation exchange capacity by extraction with 1 mol/L NH 4 OAc buffered at pH 7; exchangeable cations by atomic absorption (Ca and Mg) or flame emission spectrophotometry (Na and K); total CaCO 3 equivalent by weight loss following treatment with 6 mol/L HCl (van Wesemael 1955); active lime (i.e., 0.1 M ammonium oxalate-reactive carbonate, denoted by ACCE) according to Loeppert and Suarez (1996); electrical conductivity (EC) in a 1:5 soil:water suspension with a conductivity meter; organic C (OC) by rapid dichromate oxidation; citrate/bicarbonate/dithionite-extractable Fe (Fe d ) according to Mehra and Jackson (1960), except that extraction was performed at 298 K for 16 h; and oxalateextractable Fe (Fe ox ) according to Schwertmann (1962). Iron in the citrate/bicarbonate/dithionite and oxalate extracts was determined with the ophenanthroline colorimetric method (Olson and Ellis 1982).Olsen P was determined according to Olsen et al. (1954). For the determination of P in the 0.01 M CaCl 2 extract (CaCl 2 -P, which is a proxy for the concentration of P in the soil solution), the suspension (1:10 w:v soil:solution; 2 g of soil and 20 mL of extractant in a polyethylene flask) was horizontally shaken at 25 ± 1 ºC at 2.5 Hz for 30 min and then centrifuged at ~8 × 10 3 m s -2 for 10 min. Next, a 2 mL portion of supernatant was placed in an Eppendorf tube and centrifuged at 1.2 × 10 5 m s -2 for 15 min to remove particles with a density of 2.5 kg dm -3 and an equivalent diameter > 0.05 µm from the solution. Extraction was done in triplicate. Dissolved reactive P in all extracts was determined with the Molybdate Blue method (Murphy and Riley 1962).Zn DTPA was determined by suspending 10 g of soil in 20 mL of extractant at 25 ºC in 50 mL polyethylene tubes that were shaken at 180 rpm in a reciprocating shaker and then centrifuged at 10 4 m s -2 for 15 min (Lindsay and Norvell 1978). Zinc in the DTPA extracts was analysed using atomic absorption spectrophotometry.

Entomopathogenic fungi (EF) have so far aroused little interest as plant growth promoters or nutritional enhancers while protecting the plant against insect pests and mites. In this work, we examined the performance of Triticum durum and Triticum aestivum plants pot‐grown on two unsterilized Zn‐poor calcareous Vertisols and inoculated with Beauveria bassiana or Metarhizium brunneum by application to soil or seed dressing. The effects of fungal inoculation were found to depend on crop species, soil type, sampling time and fungus application method. While the height of the control plants tended to be significantly greater than the height of inoculated plants at early and intermediate growth stages, the trend changed at more advanced plant stage of development, 56 days after sowing (DAS). This was supported by the significant increase in aerial dry matter (ADM) in T. aestivum plants treated with B. bassiana by seed dressing (17.4%) or with M. brunneum with soil application and seed dressing (20.6 and 26.9%, respectively) 69 DAS. In T. durum, at harvest, seed dressing with B. bassiana or M. brunneum had an overall positive but not significant effect on ADM or grain yield, whereas direct application to the soil slightly decreased grain yield (6.6 and 5.5%, respectively) and ADM (5.3 and 6.1%, respectively). In T. aestivum, none of the fungus–application method combinations affected yield at harvest significantly. Fungal inoculation had little influence on nutrient uptake, whereas application to soil increased Mn uptake and grain Mn concentration in T. durum. Zinc uptake was significantly increased only in T. aestivum grown on the soil with the lowest Zn content treated with M. brunneum. Grain Zn concentration tended to be inversely related to grain yield. These results support seed dressing with EF as a promising green technology for sustainable crop protection and production with no adverse effects on plant performance.