title: Effect of Trichoderma on horticultural seedlings' growth promotion depending on inoculum and substrate type.
abstract: OBJECTIVE
  The biostimulant effect of Trichoderma spp. on horticultural crops are highly variable. Thus, practical use of Trichoderma sp. requires feasible formulated products and suitable substrates.
  
  
  RESULTS
  This study evaluates the survival and the growth-promotion effect of a Trichoderma saturnisporum rice formulation compared with a nonformulated conidia suspension (seven treatments in total), on tomato, pepper and cucumber seedlings grown in two substrates: (i) rich in organic matter (OM) and (ii) mineral substrate without OM. The results showed beneficial effects on seedling growth in the OM-rich substrate when T. saturnisporum rice formulation (mainly at maximum concentration) was applied, but the effects were opposite when the mineral substrate without OM was used. The effects were closely linked to the level of inoculum in the substrate, which was greater upon application of the formulated inoculum as opposed to the nonformulated one.
  
  
  CONCLUSIONS
  The use of rice to prepare the inoculum of T. saturnisporum seems to be promising for seedling growth in the nursery when it is applied in a substrate that is rich in organic matter, but it must be considered that under certain conditions of food shortage, Trichoderma sp. could show pathogenicity to seedlings.
  
  
  CONCLUSIONS
  This study provides evidence of the complexity inherent in the use of micro-organisms in agriculture, while also confirming that the activity of the biofertilizers based on Trichoderma depends on the type of inoculum and its concentration, as well as the properties of the medium in which the fungi develop. Further studies assessing the effectiveness or possible pathogenicity of Trichoderma in different soils under greenhouse conditions must be addressed.
authors.affiliation: Plant Production in Mediterranean Crop Systems Research Group, Department of Agronomy, University of Almeria, Almeria, Spain. jignaciomarin@gmail.com.
authors.forename: J I
authors.initials: JI
authors.lastname: Marín-Guirao
authors.affiliation: Plant Production in Mediterranean Crop Systems Research Group, Department of Agronomy, University of Almeria, Almeria, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Rodríguez-Romera
authors.affiliation: Plant Production in Mediterranean Crop Systems Research Group, Department of Agronomy, University of Almeria, Almeria, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Lupión-Rodríguez
authors.affiliation: Plant Production in Mediterranean Crop Systems Research Group, Department of Agronomy, University of Almeria, Almeria, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Camacho-Ferre
authors.affiliation: Plant Production in Mediterranean Crop Systems Research Group, Department of Agronomy, University of Almeria, Almeria, Spain.
authors.forename: J C
authors.initials: JC
authors.lastname: Tello-Marquina
mesh_terms: D059827:Agricultural Inoculants / Q000254:growth & development / Q000502:physiology*; D000383:Agriculture; D065826:Averrhoa / Q000254:growth & development / Q000382:microbiology; D002212:Capsicum / Q000254:growth & development / Q000382:microbiology*; D018553:Cucumis sativus / Q000254:growth & development / Q000382:microbiology*; D018551:Solanum lycopersicum / Q000254:growth & development / Q000382:microbiology*; D012275:Oryza / Q000254:growth & development / Q000382:microbiology; D036226:Seedlings / Q000254:growth & development* / Q000382:microbiology; D013172:Spores, Fungal / Q000254:growth & development / Q000276:immunology / Q000502:physiology; D014242:Trichoderma / Q000254:growth & development / Q000502:physiology*
keywords: biofertilizer; biostimulant; cucumber; in vitro; nursery; pepper; tomato