RESUMO

Pre-emergent herbicides can contribute to the control of weed competition in direct seeding restoration, however it is necessary to evaluate their effects on seeds of native tropical forest species. The aim of the study was to assess the potential impact of the herbicide indaziflam on the germination of 17 forest species. For this, a dosage of 180 mL of the product in 200L of water was compared to the control without herbicide. The degree of sensitivity of each species was calculated by a ratio between the percentage of germination with herbicide (GH) and the control without herbicide (GC) classifying them as: extremely sensitive (ES= (GH/GC) <0.25), sensitive (S=0.25< (GH/GC) <0.50), low sensitivity (LS=0.50< (GH/GC) <0.75), indifferent (I=0.75< (GH/GC) <1.0) and potentiated (P= (GH/GC) >1). The herbicide promoted a significant reduction in mean germination in 35% (n=6) of the species and 59% (n = 10) were sensitive or extremely sensitive to indaziflam, and only three did not germinate. On the other hand, 29.4% (n=5) showed low sensitivity or indifference to the herbicide, while seed germination was slightly increased by indaziflam to 11.7% (n=2). Pre-emergent indaziflam can be recommended in direct seeding restoration, as only 17.6% (n=3) of the species were inhibited by pre-emergent. However, the effect of indaziflam varies by species and requires further studies to support large-scale use in direct seeding.

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RESUMO

Pre-emergent herbicides can contribute to the control of weed competition in direct seeding restoration, however it is necessary to evaluate their effects on seeds of native tropical forest species. The aim of the study was to assess the potential impact of the herbicide indaziflam on the germination of 17 forest species. For this, a dosage of 180 mL of the product in 200L of water was compared to the control without herbicide. The degree of sensitivity of each species was calculated by a ratio between the percentage of germination with herbicide (GH) and the control without herbicide (GC) classifying them as: extremely sensitive (ES= (GH/GC) <0.25), sensitive (S=0.25< (GH/GC) <0.50), low sensitivity (LS=0.50< (GH/GC) <0.75), indifferent (I=0.75< (GH/GC) <1.0) and potentiated (P= (GH/GC) >1). The herbicide promoted a significant reduction in mean germination in 35% (n=6) of the species and 59% (n = 10) were sensitive or extremely sensitive to indaziflam, and only three did not germinate. On the other hand, 29.4% (n=5) showed low sensitivity or indifference to the herbicide, while seed germination was slightly increased by indaziflam to 11.7% (n=2). Pre-emergent indaziflam can be recommended in direct seeding restoration, as only 17.6% (n=3) of the species were inhibited by pre-emergent. However, the effect of indaziflam varies by species and requires further studies to support large-scale use in direct seeding.

Herbicidas pré-emergentes podem contribuir para o controle da competição de plantas daninhas em restauração por semeadura direta, porém é necessário entender seus efeitos em sementes de florestais nativas. O objetivo do estudo foi avaliar o potencial impacto do herbicida indaziflam na germinação de 17 espécies nativas de florestas tropicais. Para isso, uma dosagem ligeiramente acima da recomendada (180 mL do produto em 200 L de água) foi comparada com a testemunha sem herbicida. O grau de sensibilidade de cada espécie, foi calculado pela razão entre a porcentagem de germinação com herbicida (GH) e a testemunha sem herbicida (GC) e classificando-as como: extremamente sensível (ES= (GH/GC) <0,25), sensível (S=0,25< (GH/GC) <0,50), baixa sensibilidade (LS=0,50< (GH/GC) <0,75), indiferente - I=0,75< (GH/GC) <1,0) e potencializado (P= (GH/GC) >1). O herbicida promoveu redução significativa na média de germinação em mais de 35% (n=6) das espécies avaliadas e 59% (n=10) foram sensíveis ou extremamente sensíveis ao indaziflam e apenas três espécies não germinaram. Por outro lado, 29,4% (n=5) apresentaram baixa sensibilidade ou indiferença ao herbicida, enquanto a germinação das sementes foi levemente aumentada pelo indaziflam para 11,7% (n=2). O indaziflam pré-emergente pode ser recomendado na restauração de semeadura direta pois apenas 17,6% (n=3). O indaziflam pré-emergente pode ser recomendado na restauração de semeadura direta pois apenas 17,6% (n=3) das espécies foram inibidas pelo pré-emergente. No entanto, o efeito do indaziflam variou em função da espécie e requer mais estudos para apoiar o uso em larga escala na semeadura direta.

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AIMS: To test the suitability of the Agrobacterium tumefaciens-mediated transformation (AMT) method with Paecilomyces fumosoroseus, a fungal pathogen that causes diseases in a wide range of insects including whiteflies. METHODS AND RESULTS: Conidia of P. fumosoroseus were successfully transformed to hygromycin B resistance using the hph gene of Escherichia coli as the selectable marker. Transformation frequencies were 58.3 +/- 18.5, 98.3 +/- 24.8 and 169.7 +/- 35.5 (+/-SEM) transformants per 10(5), 10(6) and 10(7) target conidia respectively. After confirmation by PCR, transformants were subjected to Southern analysis, and the results revealed that 45% (four of nine) of the transformants contained single-copy integration of the T-DNA. CONCLUSIONS: In our AMT system, we efficiently transformed conidia of P. fumosoroseus. The employment of this method circumvents time-consuming protoplast preparation and allows the isolation of transformants containing single-copy integration of the T-DNA. SIGNIFICANCE AND IMPACT OF THE STUDY: Considering the efficiency of Ag. tumefaciens-mediated transformation, this method represents a useful tool for insertional mutagenesis to characterize genes that are important for the pathogenicity of P. fumosoroseus.

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Foram analisadas 10 amostras de vegetais e hortaliças minimamente processadas, comercializadas em hipermercados da cidade de Londrina-PR. As análises microbiológicas realizadas foram a determinação de coliformes totais e fecais, através da técnica do Numero Mais Provável (NMP) e presença de Escherichia coli através de análises bioquímicas de identificação. Os resultados obtidos para bactérias do grupo dos coliformes mostraram que 100 por cento das amostras estavam contaminadas por estes microrganismos, sendo que 80 por cento apresentaram-se fora do padrão estabelecido para coliformes fecais. Foi constatada a presença de E. coli em 80 por cento das amostras analisadas. Proteus e Enterobacter foram detectados em 20 por cento.(AU)

Were analysed 10 samples of minimally processed raw vegetables comercialyzed in Londrina-PR. The analysis of total and fecal coliforms and Escherichia coli, was realized with Most Problable Number and bioquimical identification. The results obtained for total coliform and fecal showed that 100% of the samples was contaminated, and 80% found out of the standard. E. coli was present in 80% of the samples, Proteus and Enterobacter was in 20%. (AU)

Assuntos

RESUMO

Foram analisadas 10 amostras de vegetais e hortaliças minimamente processadas, comercializadas em hipermercados da cidade de Londrina-PR. As análises microbiológicas realizadas foram a determinação de coliformes totais e fecais, através da técnica do Numero Mais Provável (NMP) e presença de Escherichia coli através de análises bioquímicas de identificação. Os resultados obtidos para bactérias do grupo dos coliformes mostraram que 100 por cento das amostras estavam contaminadas por estes microrganismos, sendo que 80 por cento apresentaram-se fora do padrão estabelecido para coliformes fecais. Foi constatada a presença de E. coli em 80 por cento das amostras analisadas. Proteus e Enterobacter foram detectados em 20 por cento.

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