Biological control of potato common scab by Bacillus amyloliquefaciens Ba01

Abstract

Potato common scab, which is caused by soil-borne Streptomyces species, is a severe plant disease that results in a significant reduction in the economic value of potatoes worldwide. Due to the lack of efficacious pesticides, crop rotations, and resistant potato cultivars against the disease, we investigated whether biological control can serve as an alternative approach. In this study, multiple Bacillus species were isolated from healthy potato tubers, and Bacillus amyloliquefaciens Ba01 was chosen for further analyses based on its potency against the potato common scab pathogen Streptomyces scabies. Ba01 inhibited the growth and sporulation of S. scabies and secreted secondary metabolites such as surfactin, iturin A, and fengycin with potential activity against S. scabies as determined by imaging mass spectrometry. In pot assays, the disease severity of potato common scab decreased from 55.6 ± 11.1% (inoculated with S. scabies only) to 4.2 ± 1.4% (inoculated with S. scabies and Ba01). In the field trial, the disease severity of potato common scab was reduced from 14.4 ± 2.9% (naturally occurring) to 5.6 ± 1.1% after Ba01 treatment, representing evidence that Bacillus species control potato common scab in nature.

A Rhizosphere-Derived Consortium of Bacillus subtilis and Trichoderma harzianum Suppresses Common Scab of Potato and Increases Yield

“…Thus, they can serve simultaneously as both a biopesticide and a biofertilizer. Successful control of soil-borne diseases, including PCS, by bioagents has been reported [ 5 , 8 ]. The impact of the bioagents, however, has been variable, especially under field conditions [ 5 ].…”

Comparative transcriptome expression analysis in susceptible and resistant potato (Solanum tuberosum) cultivars to common scab (Streptomyces scabies) revealed immune priming responses in the incompatible interaction

“…Soil pH management and crop rotation can reduce scab density, but they do not suppress the disease [ 2 , 9 ]. A viable and sustainable scab management strategy targets the development of scab-resistant potato cultivars [ 19 ] as well as the identification of common scab’s antagonists as biocontrol agents [ 1 , 14 , 51 ]. In the current study, a comparative RNA transcriptome sequencing validated by qPCR and induced gene signaling studies were conducted using two potato cultivars different by their response to scab for the purpose of unraveling genes and pathways differentially activated in this pathosystem.…”

“…As symptoms, common scab causes superficial, erumpent or deep-pitted lesions to the tuber skin following the bacterial entry through the lenticels or by direct penetration through the immature young tuber periderm [ 5 , 11 ]. The pathogen causes cell hypertrophy, cell collapse, and death during active expansion of young plant tissue [ 12 ] by the action of thaxtomin A, a secreted bacterial toxin and the key virulent factor responsible for the inhibition of cellulose biosynthesis [ 13 , 14 ]. To overcome the plant’s defense system, phyto-pathogens such as Pseumodonas syringae and Streptomyces scabies have evolved strategies to manipulate the plant hormone signalling pathways, making them vulnerable for successful infection.…”

Endophytic Bacillus velezensis strain B‐36 is a potential biocontrol agent against lotus rot caused by Fusarium oxysporum

“…B‐36 cultures and F. oxysporum spores were collected by centrifugation at 8000 g for 5 min, followed by three washes with sterilized water. Finally, 2 × 10 8 CFU per ml B‐36 and 1 × 10 4 spores per ml F. oxysporum spore suspension were prepared as described by Lin et al ().…”