Production of a bioherbicide for biological control of weeds requires a series of steps, from selection of a suitable microbial strain to final formulation. Thus, this study aimed to select fungi for production of secondary metabolites with herbicidal activity using biological resources of the Brazilian Pampa biome. Phytopathogenic fungi were isolated from infected tissues of weeds in the Pampa biome. A liquid synthetic culture medium was used for production of metabolites. The phytotoxicity of fungal metabolites was assessed via biological tests using the plant Cucumis sativus L., and the most promising strain was identified by molecular analysis. Thirty-nine fungi were isolated, and 28 presented some phytotoxic symptoms against the target plant. Fungus VP51 belonging to the genus Diaporthe showed the most pronounced herbicidal activity. The Brazilian Pampa biome is a potential resource for the development of new and sustainable chemical compounds for modern agriculture.

The chitinases have extensive biotechnological potential but have been little exploited commercially due to the low number of good chitinolytic microorganisms. The purpose of this study was to identify a chitinolytic fungal and optimize its production using solid state fermentation (SSF) and agroindustry substrate, to evaluate different chitin sources for chitinase production, to evaluate different solvents for the extraction of enzymes produced during fermentation process, and to determine the nematicide effect of enzymatic extract and biological control of Meloidogyne javanica and Meloidogyne incognita nematodes. The fungus was previously isolated from bedbugs of Tibraca limbativentris Stal (Hemiptera: Pentatomidae) and selected among 51 isolated fungal as the largest producer of chitinolytic enzymes in SSF. The isolate UFSMQ40 has been identified as Trichoderma koningiopsis by the amplification of tef1 gene fragments. The greatest chitinase production (10.76 U gds −1) occurred with wheat bran substrate at 55% moisture, 15% colloidal chitin, 100% of corn steep liquor, and two discs of inoculum at 30°C for 72 h. Considering the enzymatic inducers, the best chitinase production by the isolated fungus was achieved using chitin in colloidal, powder, and flakes. The usage of 1:15 g/mL of sodium citrate-phosphate buffer was the best ratio for chitinase extraction of SSF. The Trichoderma koningiopsis UFSMQ40 showed high mortality of M. javanica and M. incognita when applied to treatments with enzymatic filtrated and the suspension of conidia. Keywords Filamentous fungi. Chitinolytic enzymes. Biopesticides. Chitin. Nematode Highlights • Trichoderma koningiopsis UFSMQ40 presents highest production of chitinase. • The best chitinase production was found using wheat bran substrate in 55% of moisture. • Chitin in flakes was used as enzymatic inducers without altering chitinase production. • Trichoderma koningiopsis UFSMQ40 offer potential for industrial chitinase production. • The isolated fungi present high mortality effectiveness of phytopathogenic nematodes.

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RESUMOO objetivo da pesquisa foi avaliar o consumo hídrico e o desenvolvimento de hastes florais de cravina (Dianthus hybrida 'Melody'), submetida a diferentes estratégias de irrigação e tamanhos de vaso durante um ciclo de cultivo. O experimento foi conduzido em casa de vegetação do Departamento de Fitotecnia da Universidade Federal de Santa Maria, em esquema bifatorial (2x4) sendo os tratamentos utilizados dois tamanhos de vaso e quatro estratégias de irrigação, com cinco repetições cada. Ao final do ciclo de cultivo foram avaliados: altura das hastes; número de botões florais; número de gemas vegetativas por haste; número de ramificações por haste; diâmetro da haste; fitomassa de matéria fresca e fitomassa de matéria seca da parte aérea, e ainda determinado o consumo hídrico ao longo do ciclo. Os resultados demonstraram um incremento no consumo de água no decorrer do período de cultivo, porém os parâmetros de produtividade avaliados não sofreram interferência dos tratamentos. Palavras-chaves:Dianthus hybrida 'Melody', balanço hídrico, floricultura SCHWAB, N. T.; PEITER, M. X.; BELLÉ, R. A.; BACKES , F. A. A. L.; ROBAINA, A. D.; FERRAZ, R. C. WATER CONSUMPTION OF DIANTHUS MELODY UNDER DIFFERENT IRRIGATION STRATEGIES AND POT SIZES ABSTRACTThe aim of this research was to evaluate Dianthus Melody (Dianthus hybrida 'Melody') water consumption and stalk growth when submitted to different irrigation strategies and pot sizes for one crop cycle. Conducted in a greenhouse at the department of phytotechny, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil, the experiment was designed as a 2x4 factorial arrangement with two pot sizes and four irrigation strategies per treatment with five replications each. At the end of the growth cycle stem height, number of buds, number of nodes per stem, number of branches per stem, stem diameter as well as the fresh and the aboveground dry stem phytomasses were evaluated and also was determined the water consumption over the cycle. The results showed an increase in water consumption

A qualidade da água tem sido desprezada na maioria dos projetos de irrigação e os dados das análises são de difícil compreensão por parte dos irrigantes e técnicos da área. A elaboração de índices facilita a compreensão dos dados das análises, classificando estas águas em função do seu estado qualitativo. O objetivo deste trabalho foi de criar índices de qualidade da água para irrigação. Foram coletadas amostras de água superficiais de reservatórios em diferentes meses do ano sendo determinados os diferentes níveis dos parâmetros qualitativos. Através da análise dos componentes principais determinaram-se índices de qualidade da água em três classes. Os índices de qualidade da água dos reservatórios encontraram-se na faixa entre 80 e 70 na maioria dos meses. A exceção foi observada nos meses de maio e junho no reservatório S com índices de 68 e 57 respectivamente, evidenciando uma queda qualitativa das águas de irrigação. Concluiu-se que a técnica de análise multivariada é eficiente na elaboração dos índices sem perda de informação, e os indicadores que obtiveram maior peso foram o ferro total e sólidos em suspensão. Palavras SEASONAL INDEX OF QUALITY OF IRRIGATION WATER VIA MULTIVARIATE ANALYSIS ABSTRACTThe quality of water has been neglected in most irrigation projects, and data analyses are of difficult understanding for most irrigation farmers and technicians in the field. Establishing