Physiological Effects of Arbuscular Mycorrhizal Fungi (AMF), Plant Growth-Promoting Rhizobacteria (PGPRs), and Trichoderma harzianum on Tomato (Solanum lycopersicum L.) Infected with Branched Broomrape [Phelipanche ramosa (L.) Pomel]

Abstract

Tomato (Solanum lycopersicum L.), one of the world's most produced and consumed vegetables, belongs to the Solanaceae family. Branched broomrape [Phelipanche ramosa (L.) Pomel; Syn: Orobanche ramosa L.] parasitizes many cultivated plants, especially tomatoes. The parasitic weeds, for which there is no effective control method, cause serious yield and quality losses in their host crops. In this study, two different mycorrhiza (AMF) species, Funneliformis mosseae, and a commercial product, Endo Roots Soluble (ERS), along with Trichoderma harzianum T22, two different plant growth-promoting rhizobacteria (PGPR) isolates (Pseudomonas caspiana V30G2 and Bacillus velezensis V40K2), were applied to tomatoes. Additionally, a commercial product, Plant Success Great White Premium Mycorrhiza, and their combinations were used to determine the changes occurring in both the plants and the broomrape. This study investigated the number of tubercles, the levels of several oxidative stress enzymes (CAT, catalase, SOD, superoxide dismutase, and APX, ascorbate peroxidase), the level of lipid peroxidation (MDA, malondialdehyde), and the total phenolic and antioxidant contents of tomato plants infected and not infected with broomrape. Compared to the control group, the treatments were found to prevent tubercule formation at rates ranging from 60 to 72.7%. Broomrape infection caused oxidative stress in the tomatoes; the CAT and MDA contents in the broomrape-contaminated plants were greater than those in the noncontaminated plants. The results revealed that some microorganisms and biological preparations applied to tomatoes responded differently to broomrape stress through enzymatic and nonenzymatic antioxidant activities.