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Introduction--Club root can cause yield losses in crucifers between 70% to 80% and it is a serious problem of crucifers in Colombia. Objective--To evaluate biological alternatives combined with Naphthaleneacetic Acid (NA) for the management of P. brassicae in cauliflower under the conditions of the municipality of Mutiscua. Methodology--A randomized block experimental design with six treatments and three replications was established in a cauliflower culture, comparing commercial products based on the antagonist microorganisms Trichoderma harzianum, Bacillus subtilis and Burkholderia cepacia + NA, NA alone, a treatment with lime as a production standard and a whiteness. Ten plants were evaluated per experimental unit; height, stem diameter, number of leaves and incidence and severity of the disease. Finally, with the results obtained, a cost benefit analysis was developed. Results--The results showed that the applications of the biological products T. harzianum and B. subtilis combined with the growth regulator NA, although they do not curatively control the disease, reduce it when applied preventively. The cost-benefit ratio was more favorable for T. harzianum + NA, followed by lime. Although with low effectiveness, lime treatment was the cheapest alternative. Conclusions--Trichoderma harziaanum + NA, as applied in the experiment, and lime constitute non-chemical alternatives feasible for use by farmers for disease management. [ABSTRACT FROM AUTHOR]

Fungi as biological controllers are important in development of bioproducts for sustainable agriculture in the management of phytopathogens such as Sclerotinia sp., which causes white rot in lettuce, crops insomuch as infectious viability in soil lasts up until five years. Lettuce cultivation is essential in Colombia's agricultural economy, and Sclerotinia sp. causes losses until 50% of crops. The aim of this work was to evaluate in vitro the antagonistic capacity of three strains of Trichoderma sp. Tr1, Tr2 and Tr3 and, three strains of Aspergillus sp. As1, As2 and As3 against Sclerotinia sp Scl., individually and in consortia. Recovering, maintenance and evaluation of fungi was carried out by mediums as PDA, V8 Juice and Honey-Oat. The control strains -Tr1, Tr2, Tr3, As1, As2 and As3- were confronted among them and in consortia against the phytopathogen with dual technique. The consortia As1+As2+Tr2, As1+As2+Tr1, and As1+As2+Tr3 had a degree of inhibition on the phytopathogen, being more efficient the combination As1+As2+Tr1 -85,1%-; and individually the strains Tr2 and As1 with an efficiency of 95,6% and 95,1%, respectively. It was corroborated that the growth of Scl. using the consortia was not more than 14,9% in the best treatment. In none of the confrontations with the consortia was evidence of sclerotia formation, resistance structure for infection process and persistence in soils after to ten days of evaluation. [ABSTRACT FROM AUTHOR]