title: Greek indigenous streptomycetes as biocontrol agents against the soil-borne fungal plant pathogen Rhizoctonia solani.
abstract: OBJECTIVE
  To examine the biocontrol potential of multiactive Greek indigenous Streptomyces isolates carrying antifungal activity against Rhizoctonia solani that causes damping-off symptoms on beans.
  
  
  RESULTS
  A total of 605 Streptomyces isolates originated from 12 diverse Greek habitats were screened for antifungal activity against R. solani DSM843. Almost one-third of the isolates proved to be antagonistic against the fungus. From the above isolates, six were selected due to their higher antifungal activity, identified by analysing their 16S rRNA gene sequence and studied further. The obtained data showed the following: firstly, the isolates ACTA1383 and ACTA1557 exhibited the highest antagonistic activity, and therefore, they were selected for in vivo experiments using bean seeds as target; secondly, in solid and liquid culture experiments under optimum antagonistic conditions, the medium extracts from the isolates OL80, ACTA1523, ACTA1551 and ACTA1522 suppressed the growth of the fungal mycelium, while extracts from ACTA 1383 and ACTA1557 did not show any activity.
  
  
  CONCLUSIONS
  These results corresponded important indications for the utility of two Greek indigenous Streptomyces isolates (ACTA1557 and ACTA1383) for the protection of the bean crops from R. solani damping-off symptoms, while four of them (isolates OL80, ACTA1523, ACTA1551 and ACTA1522) seem to be promising producers of antifungal metabolites.
  
  
  CONCLUSIONS
  This is the first study on the biocontrol of R. solani using multiactive Streptomyces isolates originated from ecophysiologically special Greek habitats. Our study provides basic information to further explore managing strategies to control this critical disease.
authors: Department of Botany, Microbiology Group, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece.
authors: G S
authors: GS
authors: Kanini
authors: E A
authors: EA
authors: Katsifas
authors: A L
authors: AL
authors: Savvides
authors: D G
authors: DG
authors: Hatzinikolaou
authors: A D
authors: AD
authors: Karagouni
mesh_terms: D000898:Antibiosis; D061046:Biological Control Agents; D007887:Fabaceae / Q000382:microbiology*; D018525:Germination; D006115:Greece; D025282:Mycelium / Q000254:growth & development; D010935:Plant Diseases / Q000382:microbiology* / Q000517:prevention & control; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012232:Rhizoctonia / Q000254:growth & development*; D012988:Soil Microbiology; D013302:Streptomyces / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D061046:Biological Control Agents; D012336:RNA, Ribosomal, 16S