ABSTRACT
Wild (Th11, Th12 and Th650) and mutant (Th11A80.1, Th12A40.1, Th12C40.1 and Th650-NG7) Trichoderma harzianum strains were stored for 180 days at 5ºC or at 22ºC, in two types of soils. Strains recovered at 90, 120 and 180 days from the two types of soils, retained their full capacity to biocontrol Rhizoctonia solani 618, that produces crown and root rot of tomatoes. Recovery, estimated as colony forming units (cfu) of the wild and mutant strains, showed that all increased their cfu after storage independently of the type of soil and temperature, although kinetic behavior differed among strains. Ratios of recovery after storage in type B soil/ type A soil or at 22ºC/5ºC, higher or lower than one respectively, allowed to establish that Th11 and Th12 were the most appropriate strains for the biocontrol of R. solani in conditions where growth of the phytopathogen is optimal.
Subject(s)
Solanum lycopersicum , Solanum lycopersicum/enzymology , Rhizoctonia , Rhizoctonia/chemistry , Soil Treatment/methods , Trichoderma/enzymology , Trichoderma/metabolism , Trichoderma/pathogenicity , Pest Control, Biological/methods , Plant Roots/growth & development , Plant Roots , Plant Roots/chemistry , TemperatureABSTRACT
Cultivos de maracua de la region Caribe colombiana presentan problemas de marchitez y el hongo Fusariumsolani (Mart.) Sacc., estan asociado a esta patologia. Plantas de maracuya de la Estación Experimental (E.E Caribia de Corpoica) poseen este problema y por tal razon se determina el antagonismo in vitro de aislamientos de Trichoderma harzianum Rifai, frente a F. solani, aislado de plantas enfermas de maracuya (Passiflora edulis). Utilizando la tecnica de cultivo dual en platos Petri con Agar Sabouraud, se evaluaron competencia por nutrientes y espacio, micoparasitismo y porcentaje de inhibicion del crecimiento radial (PICR), empleando un diseno estadistico factorial 2x6x1 con arreglo completamente aleatorio. Se obtuvieron tres aislamientos nativos de T. harzianum (TCN-009, TCN-010, TCN-014) de suelo de Palma de Aceite (Elaeis guineensis) de la E.E Caribia, y se compararon con tres aislamientos comerciales (TCC-001, TCC-005, TCC-006). TCC-001 y TCN-014, reportaron ser mais competentes por nutrientes y espacio, con el mayor radio de crecimiento de 7,50 y 7,32 cm el dia 10, comparado a FSM-011 en el cual solo fue de 2,30 cm. Aunque, TCN-014 mostran micoparasitismo grado 4 con ambos aislamientos de F. solani y TCC-005 Unicamente con FSM-012, el cual fue mais susceptible a ser micoparasitado. En cuanto al PICR, los tratamientos con mejores porcentajes de inhibiciion fueron TA-9, TA-12 y TA-6 con valores de 70,56, 68,52 y 65,32 por ciento respectivamente. El aislamiento del patogeno mayormente inhibido fue FSM-011. Todos estos resultados demuestran que hubo antagonismo in vitro al utilizar los aislamientos nativos y comerciales de T. harzianum sobre F. solani.
Subject(s)
Fusarium/pathogenicity , Trichoderma/pathogenicityABSTRACT
A case report of an intrahospitalary Trichoderma longibrachiatum peritonitis in a female 13-year-old pediatric patient who had been previously diagnosed a terminal chronic renal insufficiency while being under peritoneal dialysis is presented. Nowadays literature recognizes certain members of the genus Trichoderma to be opportunistic pathogens of increasing occurrence in immunocompromised patients. The above girl received a satisfactory Amphoterin B treatment yet she died due to an hypertensive emergency appearing secondarily to her basic pathology.