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The objective of the present work was to evaluate the in vitro vegetative compatibility among Cuban strains of the entomopathogenic fungi Lecanicillium lecanii (Zim.) Zare and Gams, Beauveria bassiana (Balsamo) Vuilleming, Isaria fumosorosea (Wise) Brown and Smith, and Metarhizium anisopliae (Mestch) Sorokin, previously selected as biological control agents for harmful insects. Compatibility was evaluated by the Dual Culture method and the percentage of inhibition of radial growth (PIRG) was determined. The type of interaction of microorganisms was classified according to the scale recommended by the literature. In the confrontation tests carried out, no projection of the hyphae of any of the species onto the other species was observed, suggesting an indirect growth inhibition through the excretion of metabolites. In the first seven days, distant mutual inhibition was observed between I. fumosorosea and the rest of the fungi evaluated and the interaction was classified as type C; the PIRG varied between 15.9 - 36.6 %. The growth of B. bassiana also showed inhibition against L. lecanii and M. anisopliae with PIRGof 10.99% and 17.6%, respectively, and the interaction was classified as type E. In the rest of the interactions, no inhibitions were observed. All fungi were compatible so that they can be applied combined with each other in insect pest management. [ABSTRACT FROM AUTHOR]

The objectives of the work were I) to establish the compatibility between Trichoderma asperellum Samuels et al. and Pseudomonas protegens Ramette et al. under laboratory conditions and II) to determine the efficacy of the biological products based on both organisms in controlling early blight. For the study in the field during two campaigns, plots of 27 m² were used in a non-randomized block design. Compatibility of both products was determined in the laboratory. In the field, eleven treatments were used in the first campaign, and the best ones were selected for being applied in the next campaign. In the treatments to the soil, a conidial suspension of T. asperellum strain Ta. 85 at a concentration of 7x107 CFU were applied to the soil at a rate of 8 L per treatment. In the first campaign, once the symptoms of the disease were detected, the aforementioned biofungicides, at the respective concentration of 7x107 CFU.ml-1 and 108 CFU.ml-1, were applied to the foliage at a rate of 8 L per treatment. In the second campaign, the biofungicides were applied to the foliage when the symptoms were detected and 15 days later. There was compatibility between the biological products, indicating that both can be applied together in the biological control of early blight. The treatments with T. asperellum to the soil plus the tubers plus the combination of T. asperellum and P. protegens with double applications to the foliage and T. asperellum to the soil plus the tuber plus double application of Pseudomonas to the foliage were significantly effective in reducing the disease, respecting to the control, where the latter treatment stood out. These results suggest that these products could be promising for the biological control of this pathogen in the potato crop under field conditions. [ABSTRACT FROM AUTHOR]

This study was aimed at evaluating the effect of different commercial pesticides, the aqueous and alcoholic extracts of several plants, and basidiocarps of Pycnoporus sanguineus L. on Beauveria bassiana Bals. Vuill. The commercial pesticides studied were Agro-mós, Agro-fos, Bion, Biogermex, Citronella oíl, Forth, Pironim, Bordeaux mixture, Planta Clean, and Sulphur-lime mixture, at the concentration recommended in the product labels (RC), the half of this concentration (1/2 CR), and the two-fold concentration (2 CR). The plant extracts were from Rosmarinus officinalis L., Cymbopogon citratus Stapf, C. winterianus Jowitt, Laurus nobilis L., Azadirachta indica A. Juss, Ricinus communis L., Melia azedarach L., Corymbia citriodora Hook, Ruta graveolens L., Curcuma longa L., Cinnamomum zeylanicum Blume) All the extracts and the basidiocarps of P. sanguineus were used at a 10% concentration. All the products were sprayed over B. bassiana previously inoculated to the culture medium (BDA). The parameters evaluated were germination, CFU, vegetative growth, and conidia production. Despite the deleterious effect of the commercial phytosanitary products on some of the parameters, they were compatible with B. bassiana, the same as the plant extracts were. However, the combined use or subsequent applications of the products here tested must be avoided before the 48 hours of B. bassiana application. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the compatibility of some herbicides used to control the arvenses in the rice crop with three strains (T.17, T.75 and T.78) of Trichoderma asperellum Samuels. The technique used was that of poisoned cultures at different herbicide concentrations. Three herbicides of frequent use in the crop (fenoxaprop-p-ethyl; bispiribac-sodium; 2,4D amina salt) were tested starting from the field dose (0,1D = 10 times lower, D = recommended dose and 10D = 10 times higher). After 72 hours, the effect of the concentrations of the products on the mycelial growth, sporulation and germination 12 hours after the trial setting was determined. The residual effect of the product was evaluated in malt agar on day 7. The results showed that the concentrations of D and 10D of the fenoxaprop-p-ethyl products and 2,4D amina salt affected the mycelial growth of the strains T.17 and T.75; however, germination at the 0,1D concentration was not affected. None of the strains evaluated were affected by bispiribac - sodium. Even on day 7, the fenoxaprop-p-ethyl products and 2,4D amina salt at the concentrations of 10D showed residual effects on the strains T.17 and T.75. The herbicide bispiribac - sodium turned out to be compatible with the three strains of T. asperellum evaluated. [ABSTRACT FROM AUTHOR]