Endophytic Beauveria bassiana Induces Oxidative Stress and Enhances the Growth of Fusarium oxysporum-Infected Tomato Plants

Abstract

Studying the mechanisms through which endophytic fungi confer protection to host plants against parasites will contribute toward elucidating the endophytic fungi–plant–pathogen relationship. In this study, we evaluated the effects of endophytic Beauveria bassiana on the antioxidant activity, oxidative stress, and growth of tomatoes infected with the fusarium wilt pathogen, Fusarium oxysporum f. sp. lycopersici (FOL). Tomato seedlings were inoculated with B. bassiana conidia and then contaminated with FOL experimentally. Four treatments (Control [T1], FOL only [T2], B. bassiana only [T3], and B. bassiana and FOL [T4]) were assessed. The plants from the B. bassiana and FOL treatment (T4) were significantly taller (DF = 3, 56; p < 0.001) and produced more leaves and aerial part biomass than those treated with only FOL (T2). Remarkably, plants in the two treatments with FOL (T2 and T4) had the lowest antioxidant activities; meanwhile, plants from the FOL treatment (T2) had the lowest ROS (superoxide and hydroxyl radicals) contents. Broadly, strong positive correlations between ROS and all the plant growth parameters were recorded in this study. While the current results revealed that the endophytic entomopathogen B. bassiana enhanced antioxidant capacity in plants, it did not improve the antioxidant capacity of F. oxysporum-infected plants. It is possible that the pathogenic FOL employed a hiding strategy to evade the host immune response and the antagonistic actions of endophytic B. bassiana. In conclusion, B. bassiana inoculum enhanced the growth of tomatoes infected with FOL, induced higher oxidative stress in both F. oxysporum-infected and -uninfected tomatoes, and improved antioxidant activities in plants inoculated with B. bassiana only.

The Endophytic Entomopathogenic Fungus Beauveria bassiana Alleviates Adverse Effects of Salt Stress in Potato Plants

“…The high activity of the antioxidant system and consequent downregulation of MDA indicate the absence of a pathological imbalance within the system of stress-induced protective mechanisms. An increase in the activity of antioxidant enzymes has been documented in most papers on the adaptogenic properties of endophytic fungi in relation to plants grown under salinity stress [60,[62][63][64]67,68] and after the application of B. bassiana [46,47,92]. In our experiments, there were no significant changes in the MDA concentration of the roots, regardless of the presence or absence of salt and/or the endophyte.…”

Biological and physiological effects in Bemisia tabaci feeding on tomatoes endophytically colonized by Beauveria bassiana

“…37,38 In the last decades, it has been demonstrated that Beauveria bassiana can be artificially introduced into tomato using different inoculation methods such as leaf spraying, root irrigation, stem injection, and seed treatments. 21,28,39,40 These methods can influence the colonization efficiency of Beauveria bassiana within the tomato tissues. In our early research, we found that colonization efficiency reached 100% in 14 days when tomatoes were inoculated with Beauveria bassiana Bb252 by leaf spraying.…”

“…Endophytic EPF of plants inhabit plant tissues over a long period and provide many benefits to plants, such as reducing the influence of abiotic factors on the control effect of EPF 37,38 . In the last decades, it has been demonstrated that Beauveria bassiana can be artificially introduced into tomato using different inoculation methods such as leaf spraying, root irrigation, stem injection, and seed treatments 21,28,39,40 . These methods can influence the colonization efficiency of Beauveria bassiana within the tomato tissues.…”

Symbiosis of Plants with Mycorrhizal and Endophytic Fungi

“…Nchu et al [15] deepened the relationship between the endophyte fungus and the plant pathogen. They studied the effects of Beauveria bassiana on the growth of tomato plants infected with Fusarium oxysporum f. sp.…”