title: [The effect of the formulation on the shelf-life of biopesticides based on two Colombian isolates of Trichoderma koningiopsis Th003 and Trichoderma asperellum Th034].
abstract: BACKGROUND
  Four biopesticide prototypes formulated as dispersible granules and dry powders based on 2 Colombian isolates of Trichoderma koningiopsis (Th003) and T. asperellum (Th034) were developed. These microorganisms have antagonist activity against Fusarium oxysporum f. sp. lycopersici and Rhizoctonia solani with a reduction in incidence of between 70 and 100% in tomato crops and potato crops, respectively.
  
  
  OBJECTIVE
  To determine the effect of the formulation on the shelf-life of 4 biopesticides based on T. koningiopsis Th003 and Trichoderma asperellum Th034 at 3 different temperatures.
  
  
  METHODS
  The formulation effect was determined by evaluating the germination of unformulated and formulated conidia (dispersible granules and dry powder) stored at 8, 18 and 28°C for 18 months. Germination kinetics were used to estimate the shelf-life by using different mathematical models (zero order, first order, second order, Higuchi model, Korsmeyer-Peppas model and polynomial model).
  
  
  RESULTS
  The products showed high stability of the conidia germination when they were stored at 8 and 18° C, with shelf-lives of 14.4 and 13.9 months for dry powder based on Th003, and 12.0 and 10.8 months for dry powder based on Th034, respectively. Prototypes formulated as dispersible granules stored at the same temperatures (8 and 18°C) showed lower shelf-lives, with values of 11.6 and 10.9 months for the Th003 product, and 10.7 and 7.2 months for the dispersible granules based on Th034. Significant reductions in germination were observed on unformulated conidia at all storage temperatures evaluated.
  
  
  CONCLUSIONS
  The formulation type affected the conidia stability of the 2 Trichoderma spp. Colombian isolates. Dry powder was the prototype with the highest stability and shelf-life at all temperatures evaluated.
authors: Laboratorio de Control Biológico, Centro de Biotecnología y Bioindustria, Corporación colombiana de investigación agropecuaria CORPOICA, Mosquera, Cundinamarca, Colombia. adrianitasantos@yahoo.com
authors: Adriana
authors: A
authors: Santos
authors: Magda
authors: M
authors: García
authors: Alba Marina
authors: AM
authors: Cotes
authors: Laura
authors: L
authors: Villamizar
mesh_terms: D002626:Chemistry, Pharmaceutical; D003105:Colombia; D018556:Crops, Agricultural / Q000382:microbiology; D004355:Drug Stability; D004356:Drug Storage; D005079:Excipients / Q000737:chemistry; D005659:Fungicides, Industrial / Q000737:chemistry*; D018551:Solanum lycopersicum / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology / Q000517:prevention & control; D011208:Powders; D011198:Solanum tuberosum / Q000382:microbiology; D013045:Species Specificity; D013172:Spores, Fungal / Q000254:growth & development; D013696:Temperature; D014242:Trichoderma / Q000254:growth & development / Q000502:physiology*
chemical_list: D005079:Excipients; D005659:Fungicides, Industrial; D011208:Powders