Effects of entomopathogenic fungi on durum wheat nutrition and growth in the field

Abstract Entomopathogenic fungi (EF), which are widely used as biological insecticides, have been shown to colonize a wide range of plants influencing their performance. Also, recent studies under controlled conditions have revealed that EF can additionally act as plant growth promoters and nutritional enhancers. In this work, we examined the effects of the EF species Beauveria bassiana and Metarhizium brunneum on durum wheat (Triticum durum L.) plants grown on calcareous Vertisols in two field experiments spanning two consecutive seasons. The fungi were either directly applied to the soil (2015–2016) or used for seed dressing (2016–2017). With the soil application treatment, neither fungus was detected in soil 30 days after sowing (DAS) and only M. brunneum was present in plants (up to 16.6 % of them). With seed dressing, B. bassiana and M. brunneum colonized plant tissues in up to 16.6 and 4.1 %, respectively. Both fungi increased aerial dry matter in 5 of the 7 samplings conducted at early and mid-crop growth stages [viz., before Zadok’s stage 55 (heading)] in the two seasons, the increase being significant at the P