Selection of Bacterial Strains for Control of Root-Knot Disease Caused by Meloidogyne incognita

Abstract

Root-knot disease caused by Meloidogyne incognita leads to significant crop yield losses that may be aggravated by the association with pathogenic fungi and bacteria. Biological agents can be effectively used against the complex disease of root-knot nematode and pathogenic fungi. In this study, 35 bacterial strains were analyzed for their in vitro nematicidal, antagonistic and growth stimulation activities. Based on results from the in vitro assays, grow-box experiments on tomato and cucumber were carried out with the strain BZR 86 of Bacillus velezensis applied at different concentrations. Effects of B. velezensis BZR 86 on the development of root-knot disease were evaluated by recording root gall index, number of galls and number of eggs in egg masses. Application of B. velezensis BZR 86 noticeably decreased the development of root-knot disease on tomato and cucumber plants, as well as significantly increased growth and biomass of cucumber plants in accordance with bacterial concentration. This study seems to demonstrate that strain B. velezensis BZR 86 could be an additional tool for an environmentally safe control of root-knot disease on horticultural crops.

Genomic, Antimicrobial, and Aphicidal Traits of Bacillus velezensis ATR2, and Its Biocontrol Potential against Ginger Rhizome Rot Disease Caused by Bacillus pumilus

“…Furthermore, some B. velezensis strains encoded lignocellulolytic enzymes and exhibited the potential for degrading lignocellulosic biomass [33]. In addition, B. velezensis BZR 86 significantly controlled the root-knot disease on plants and noticeably increased growth and biomass of plants [34]. It was reported that bacterial treatment with B. velezensis YC7010 elicited the induced systemic resistance (ISR) and noticeably decreased settling, feeding, and reproduction of green peach aphid on Arabidopsis leaves [35].…”

Microbial landscapes of the rhizosphere soils and roots of Luffa cylindrica plant associated with Meloidogyne incognita

“…On the contrary, genera Arthrobacter , Bacillus , and Chujaibacter decreased their abundance. Bacillus bacteria shows significant anti-nematode activity by producing plantazolicin (such as B. amyloliquefaciens FZB42) or inducing systemic resistance in plants (such as B. atrophaeus GBSC56) ( Liu et al, 2013 ; Xiong et al, 2015 ; Cheng et al, 2020 ; Ayaz et al, 2021 ; Migunova et al, 2021 ; Yin et al, 2021 ). Moreover, Bacillus colonization was negatively correlated with pathogen abundance and disease incidence ( Xue et al, 2015 ).…”

“…Culture supernatant of Streptomyces hydrogenans DH-16 lowers the root galls in the infested plants by M. incognita and promotes the growth of Solanum lycopersicum seedlings ( Sharma et al, 2020 ). The application of B. velezensis BZR 86 significantly decreases the development of root-knot disease in tomato and cucumber vegetables ( Migunova et al, 2021 ). Pot experiment suggested that Pseudomonas simiae strain MB751 exhibits significant nematicidal activity against M. incognita with approximately 80% mortality toward pre-parasitic second stage juveniles (pre-J2s; Sun et al, 2021 ).…”

Application Potential of Bacterial Volatile Organic Compounds in the Control of Root-Knot Nematodes

“…Treatments of potato plants with a recombinant B. subtilis strain, which secreted plant-defense elicitor peptide StPep1, effectively reduced root galling caused by Meloidogyne chitwoodi [ 68 ]. The treatment of cucumber and tomato plants with Bacillus velezensis BZR 86 significantly reduced the development of root-knot disease caused by M. incognita , and, as a result, the growth of the plants was enhanced [ 69 ].…”