Effects of entomopathogenic fungi on growth and nutrition in wheat grown on two calcareous soils: Influence of the fungus application method

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. The effect of entomopathogenic fungi (EF) on wheat performance and nutrition depends on soil, specie and application method used. Durum wheat is more sensitive to the presence of EF than bread wheat. Soil application may cause a cost for the host plant, in durum wheat mainly. However, seed dressing method generally enhance the yield of both crops. 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.