Biological Control of Potato Brown Leaf Spot Disease Caused by Alternaria alternata Using Brevibacillus formosus Strain DSM 9885 and Brevibacillus brevis Strain NBRC 15304

Abstract

Brown leaf spot is one of the prevalent diseases caused by Alternaria alternata in different growing areas of potato worldwide. Eight A. alternata isolates were screened from forty-two isolates collected from different potato growing regions in four Egyptian governorates viz, North Sinai (Baloza), Beheira (El-Nubaria and Wadi El-Natrun), Ismailia (Abu Suweir, Fayed and Tell El-Kebir), Sharqia (New Salheya and El-Husseiniya). The virulence of the isolates was tested based on the Per cent of Disease Index (PDI) which ranged from 28.2% to 70.3% PDI by Alternaria isolates of Baloza and Fayed respectively. Two bacterial strains "Brevibacillus formosus strain DSM 9885, and Brevibacillus brevis strain NBRC 15304 were selected to control of A. alternata. The bacterial strains have a higher inhibitory effect on mycelial development and spore germination of A. alternata. To determine the effects of the bacterial strains on disease index and severity, the most virulent of A. alternata isolates were selected for greenhouse experiments where the potato plants were sprayed with bacterial strains individually and mixture treatments. Superior effect of treatments in disease reduction was observed when the two bacterial strains were combined. The effect of leaf age was studied where the leaf position has significant effect on disease progress. The changes of soluble protein in potato leaves due to Brevibacillus strains application were studied. Protein profiling by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the plant treated with mixture of biocontrol agents able to synthesize some new proteins with maximum number of bands followed by treatment by B. formosus strain. The presence or absence of the bands in protein profiling might be responsible for resistance response against A. alternata in potato. The present work suggests that use of B. formosus strain DSM 9885, and B. brevis strain NBRC 15304 could be considered as potential management tools for reducing the impact of A. alternata causing brown leaf spot disease on potato.

Strategies for the Management of Leaf Blight Disease Caused by Alternaria alternata in Gloriosa superba (L.)

“…Basamma and Shripad Kulkarni (2017) found that foliar application of B. subtilis at 10g/l reduced the early blight incidence in tomato caused A. alternata and increased the plant growth promotion by recording the highest number of branches, fruits and fruit weight per plant. Ahmed (2017) tested the efficacy of two bacterial antagonists, namely Brevibacillus formosus strain DSM 9885 and Brevibacillus brevis strain NBRC 15304, against the brown leaf spot of potato under greenhouse condition. The combined application of these two antagonists was found to be superior in their efficacy against disease than the individual applications.…”

Brevibacillus Spp. in Agroecology: The Beneficial Impacts in Biocontrol of Plant Pathogens and Soil Bioremediation

“…Brevibacillus brevis produced useful peptide antibiotic gramicidin S, which attacks the lipid bilayer of the membranes of organisms [28]. Brevibacillus is playing an important role as bio-remediation factor to combat the contamination resulted by toxic metals and reduce the environmental pollution in agricultural soils, water, and the atmosphere.…”

“…effects in suppression of Salvia officinalis wilt and root rot diseases effectiveness probably due to the production of several inhibitory metabolites like HCN, chitinase, and siderophore. Ahmed[28] studied the effect of Brevibacillus formosus strain DSM 9885 and Brevibacillus brevis strain NBRC 15304 as a biological control agent on potato brown leaf spot disease caused by Alternaria alternata, the study demonstrated that the use of the tested Brevibacillus strains could enhance resistance to brown leaf spot in potato. The linear mycelial growth and spore germination of A. alternata was inhibited by both of tested bacterial isolates with reduction of disease symptoms, where the effects were determined in vitro through detached leaves and under greenhouse conditions.…”

“…Protein profiling by SDS-PAGE revealed that some bands of protein are produced due to the Brevibacillus as biocontrol agents. So Ahmed[28] concluded that B. formosus strain DSM 9885, and B. brevisstrain NBRC 15304 could be considered as part of management tools for reducing the impact of A. alternata causing brown leaf spot disease on potato[31,32].…”

Determination of Some Biological Control Agents Against Alternaria Fruit Rot in Quince

“…Biological control method is a suitable for post harvest applications (Mari and Guizzardi, 1998) due to storage conditions where are controlled many parameters and biological control agents can confront with the pathogens, directly (Wilson and Pusey, 1985). In order to prevent post harvest losses, different researchers were determined fungi, bacteria and yeasts used successfully in in vitro and in vivo assay in biological control of dry and wet rot in fruits (Schisler et al, 1997;Kotan et al, 1999Kotan et al, , 2002Roco and Perez, 2001;Sadfi et al, 2002;Sempere and Santamarina, 2007;Panwar et al, 2013;Pane andZaccardelli, 2015, Ghosh et al, 2016;Ahmed, 2017).…”