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Biological control agents are alternatives to chemical pesticides in the management of plant diseases. Currently, hundreds of bioproducts are commercially available in international market varying mainly in antagonistic microorganisms and formulation. We screened four Trichoderma-based products as to their efficacy in controlling Sclerotinia stem rot (SSR) under protected and field environments and their effect on soybean seeds' sanity and physiological qualities. We also tested application technologies through seed microbiolization and foliar spraying to deliver the microorganisms, and their compatibility with chemical fungicides. In vitro assays showed that all Trichoderma strains were antagonistic to S. sclerotiorum evidencing hyperparasitic activity. Moreover, the bioproducts reduced fungi incidence on soybean seeds, promoted faster seedling emergence and did not hamper seeds' vigor. Increases of 14 and 37% were registered for root length and shoot fresh weight over that of the untreated control indicating potential application of the bioproducts as soybean growth promoters. Thiophanate-methyl and procymidone were the most compatible, without drastically affecting spore germination or mycelium growth. Under field conditions, all Trichoderma strains reduced SSR incidence and increased soybean grain yield. Formulation interferes on bioproducts' viability and efficacy deserving special attention upon development.

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B.C.M. Juliatti et al. 2had lower AUDPC and severity values, during the monocycle experiment. We conclude that ASR is shifting to a longer incubation period and fast sporulation induction after uredinia formation. These genotypes can be used in the field, with less need for fungicides helping avoid the emergence of new ASR pathotypes and races with low sensitivity to currently used fungicides.

According to IBGE data, in 2016, Brazil produced closer to 56 thousand hectares of rubber tree generating a total latex production of 315.62 tons in commercial areas and 1.6 thousand tons in native forests. But this growth in crop production is related to the raise of economic losses generated by foliar and bark (panel) diseases caused by Phytophthora spp, Colletotrichum sp., Lasiodiplodia spp., Colletotrichum sp., Ceratocystis fimbriata, Microcyclus ulei (leaf blight) and the leaf anomaly that we call here as "Green Spot". Also, due to the tapping method and the incisions or "injuries" made in this process, opportunistic pathogens can usually infect and end up growing in the bark. This type of infection that is also difficult to control with the adoption of chemical fungicides, can create additional damage to the rubber panels. Pathogens such as Oidium heveae, C. gloeosporioides (anthracnosis), Phomopsis sp. and Phytophthora spp. were identified in 42% of the areas of growers or farms. Treatments T3-(thiophanate-methyl (350 g.ha-1 active ingredient) and T4-(metiram (1.75 kg.ha-1 active ingredient)) were superior against rot diseases in the bark of rubber trees. It was described for the first time the anomaly of the green spot associated to the Tenuipalpus heveae mite in 65% of the samples and had its etiology confirmed by artificial inoculation in rubber tree seedlings. In the USP-ESALq, Dr. Kitajima, E., did not confirm the presence of rhabdovirus-like particles common to tenuipalpids that transmit the virus in coffee and citrus (nuclear and cytoplasmic viruses).

Sclerotia are resistance structures that allow several soil-borne plant pathogens to survive for extended periods of time. The white mold disease, caused by Sclerotinia sclerotiorum and the stem rot in Allium spp., caused by Stromatinia cepivora are examples of destructive pathogens in which sclerotia are the central survival structure in their life cycle. In this chapter, we explore the information on the use of Trichoderma to manage sclerotia-producing pathogens in Brazil. There are 34 registered commercial products registered in Brazil, and most of them are recommended to manage sclerotia-producing fungi. The mechanisms of action of Trichoderma against these pathogens involve mainly mycoparasitism. The number of species employed as active ingredients of these commercial products is very limited, although many other species have shown a high potential against these pathogens. The white mold pathogen in soybean was taken as an example of field management, where the technical recommendations are detailed. This management involves other practices in addition to the application of Trichoderma in an integrated manner, and they are essential to manage this disease in the field in Brazil.

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