Endophytic Strain Bacillus subtilis 26DCryChS Producing Cry1Ia Toxin from Bacillus thuringiensis Promotes Multifaceted Potato Defense against Phytophthora infestans (Mont.) de Bary and Pest Leptinotarsa decemlineata Say

Novel properties of a previously obtained Bacillus subtilis 26DCryChS strain are described. TheB. subtilis26DCryChS strain is able to produce Cry1Ia delta-endotoxin fromB. thuringiensisB-5351 and to exist in internal plant tissues of potato plants in the same manner as the endophyticB. subtilis26D source strain (487 +/- 53 and 420 +/- 63 CFU*10(3)/g, respectively).B. subtilis 26DCryChS, as much as the originalB. subtilis 26D strain, inhibited mycelium growth of oomycetePhytophthora infestans(Mont.) de Bary and reduced late blight symptoms development on plants by 35% compared with non-treated ones, as well as showed insecticidal activity againstLeptinotarsa decemlineata. Production of the fluorescent GFP protein in theB. subtilis 26D genome allowed visualizing the endophytes around damaged sites on beetle intestines.Bacillusstrains under investigation induced systemic resistance toP. infestansandL. decemlineatathrough the activation of the transcription of PR genes in potato plants. Thus, theB. subtilis 26DCryChS strain was able to induce transcription of jasmonate-dependent genes and acquired the ability to promote transcription of a salicylate-dependent gene (PR1) in plants infected with the late blight agent and damaged by Colorado potato beetle larvae. TheB. subtilis 26DCryChS strain could be put forward as a modern approach for biocontrol agents design.