Biological control of bacterial plant diseases with Lactobacillus plantarum strains selected for their broad‐spectrum activity

Abstract

The use of lactic acid bacteria (LAB) to control multiple pathogens that affect different crops was studied, namely, Pseudomonas syringae pv. actinidiae in kiwifruit, Xanthomonas arboricola pv. pruni in Prunus and Xanthomonas fragariae in strawberry. A screening procedure based on in vitro and in planta assays of the three bacterial pathogens was successful in selecting potential LAB strains as biological control agents. The antagonistic activity of 55 strains was first tested in vitro and the strains Lactobacillus plantarum CC100, PM411 and TC92, and Leuconostoc mesenteroides CM160 and CM209 were selected because of their broad‐spectrum activity. The biocontrol efficacy of the selected strains was assessed using a multiple‐pathosystem approach in greenhouse conditions. L. plantarum PM411 and TC92 prevented all three pathogens from infecting their corresponding plant hosts. In addition, the biocontrol performance of PM411 and TC92 was comparable to the reference products (Bacillus amyloliquefaciens D747, Bacillus subtilis QST713, chitosan, acibenzolar‐S‐methyl, copper and kasugamycin) in semi‐field and field experiments. The in vitro inhibitory mechanism of PM411 and TC92 is based, at least in part, on a pH lowering effect and the production of lactic acid. Moreover, both strains showed similar survival rates on leaf surfaces. PM411 and TC92 can easily be distinguished because of their different multilocus sequence typing and random amplified polymorphic DNA profiles.

Review report on the role of bioproducts, biopreparations, biostimulants and microbial inoculants in organic production of fruit

“…The bacteria were able to live on the leaves at the concentration of about 10 4 CFU per leaf. The test strains reduced disease incidence from 40% to 10-12% (Daranas et al 2018).…”

Mechanistic insights into host adaptation, virulence and epidemiology of the phytopathogenXanthomonas

“…Indeed, many Bacillus and Streptomyces strains have been shown to have a broad range biocontrol effect (Shafi, Tian and Ji 2017;Vurukonda, Giovanardi and Stefani 2018) and several have been commercialised (Table 2). Numerous studies have demonstrated that foliar treatment with commercial or naturally isolated bacilli and Streptomyces strains significantly reduced Xanthomonas caused diseases in multiple crops in field trials (Van Hop et al 2014;Thapa and Babadoost 2016;Daranas et al 2019).…”

Exploring Rain as Source of Biological Control Agents for Fire Blight on Apple

“…In contrast, Wei et al (2016) found that the relative abundance of a potential BCA (Bacillus subtilis) in strawberry leaves was found to be depleted by 50% 8 days post-inoculation under field conditions. Another study found the population size of a potential Lactobacillus plantarum BCA decreased significantly 10 days after inoculation on kiwifruit, strawberry, and Prunus leaves, even under stable greenhouse conditions (Daranas et al, 2019). When compared to those BCAs, which were isolated from plants or soil, our rain-borne isolate BAV2934 demonstrated better survival on aerial plant surfaces.…”

“…However, since differences in bacterial survival rate depend on the type of plant surface (Pujol et al, 2006;Bonaterra et al, 2007) and environmental conditions (Nuclo et al, 1998), we cannot make general conclusions before testing our rain-isolated bacteria in different geographic locations. Some BCAs have a broad spectrum of inhibition against many plant pathogens (Ishimaru et al, 1988;Mora et al, 2015;Daranas et al, 2019). Here, we observed that our initial 9 rain-isolated bacteria have the ability to suppress a wide range of bacterial, fungal, and oomycetes pathogens in vitro ( Supplementary Table S2).…”