Antagonistic activity of endophytic actinobacteria from native potatoes (Solanum tuberosum subsp. tuberosum L.) against Pectobacterium carotovorum subsp. carotovorum and Pectobacterium atrosepticum

Abstract

Background The native potatoes (Solanum tuberosum subsp. tuberosum L.) grown in Chile (Chiloé) represent a new, unexplored source of endophytes to find potential biological control agents for the prevention of bacterial diseases, like blackleg and soft rot, in potato crops. Result The objective of this study was the selection of endophytic actinobacteria from native potatoes for antagonistic activity against Pectobacterium carotovorum subsp. carotovorum and Pectobacterium atrosepticum, and their potential to suppress tissue maceration symptoms in potato tubers. This potential was determined through the quorum quenching activity using a Chromobacterium violaceaum ATCC 12472 Wild type (WT) bioassay and its colonization behavior of the potato plant root system (S. tuberosum) by means of the Double labeling of oligonucleotide probes for fluorescence in situ hybridization (DOPE-FISH) targeting technique. The results showed that although Streptomyces sp. TP199 and Streptomyces sp. A2R31 were able to inhibit the growth of the pathogens, only the Streptomyces sp. TP199 isolate inhibited Pectobacterium sp. growth and diminished tissue maceration in tubers (p ≤ 0.05). Streptomyces sp. TP199 had metal-dependent acyl homoserine lactones (AHL) quorum quenching activity in vitro and was able to colonize the root endosphere 10 days after inoculation. Conclusions We concluded that native potatoes from southern Chile possess endophyte actinobacteria that are potential agents for the disease management of soft rot and blackleg.

Potential of actinobacteria as biocontrol agents to Xanthomonas oryzae pv. oryzae in vitro

“…The dual culture method analyzed the antibacterial activity of actinobacteria isolates [12]. Actinobacteria cultures were cultivated for 14 days at room temperature in 100 ml of ISP 2 liquid medium.…”

“…Fungi and pathogenic bacteria such as Phytophthora palmivora, Bacillus subtilis, Pantoea dispersa, and Ralstonia syzygii have been reported to be inhibited by actinobacteria selected from the soil. According to [12], Streptomyces sp. strains TP199 and A2R31 can limit the growth of Pectobacterium sp.…”

Antioxidant Activity and Phytopathogenic Control of Extracts and Fraction from Struthanthus calophyllus A.C.Sm. (Loranthaceae)

“…This is reflected in the time, quality, and production costs of the crops, with the grower being directly affected, and even the agricultural production of the region or country. Studies have been carried out on various aspects of phytopathogenic bacteria, such as methodologies for the identification and evaluation of symptoms, isolation and characterization of virulent strains, [24] development of diseases, abiotic controlling agents, [25] biologic control, [26] evaluating the effectiveness of antagonistic microorganisms, or even pathogen resistant plant varieties from genetic manipulation. [27] In this way, the integration of this knowledge can allow optimizing these properties in plants and microorganisms to overcome the limitations in their application, reducing costs and improving the processes involved.…”

Latent Infestation of Potato Tubers with Soft Rot and Ring Rot Pathogens under Changing Weather Conditions in Ukraine

“…For each year (2020 and 2021), potato seed sets from newly harvested crops without visual symptoms of diseases were used for the experiments. In 2020, 1661 potato tubers from 8 regions of Ukraine, including the Odesa (148 tubers), Kyiv (763), Donetsk (30), Kherson (90), Cherkasy (90), Mykolaiv (60), Dnipropetrovsk (390), and Zhytomyr (90) regions were examined. In 2021, 1160 potato tubers from the same 8 regions of Ukraine were investigated: Odesa (40 tubers), Kyiv (430), Donetsk (90), Kherson (120), Cherkasy (120), Mykolaiv (120), Dnipropetrovsk (150), and Zhytomyr (90) regions (Fig.…”

“…Th e quality and quantity of the potato crop are signifi cantly infl uenced by climatic conditions during planting, growing, and harvesting season, since abiotic and biotic stresses acting in tandem (disease develops only under permissive environmental conditions) cause huge crop losses [29]. One of the biggest threats to potato productivity is the loss caused by bacterial diseases, which, once introduced into the crop, can persist and spread in the agricultural environment through latent (asymptomatic) infections [30]. Th e major source of fi eld inoculum for bacteria is the latent-ly infected seed (mother) tubers [31].…”