Desempenho de fosfitos de potássio no manejo de mofo branco em soja
Soybean plays an important role in the Brazilian agriculture being one of the products most exported by the country. Its yield may be affected by diseases such as white mold, caused by the fungus Sclerotinia sclerotiorum Lib. de Bary, which, under favorable field conditions prevents the crop of expr...
| Autor principal: | Camochena, Rubia Cristiani |
|---|---|
| Formato: | Tese |
| Idioma: | Português |
| Publicado em: |
Universidade Tecnológica Federal do Paraná
2016
|
| Assuntos: | |
| Acesso em linha: |
http://repositorio.utfpr.edu.br/jspui/handle/1/1620 |
| Tags: |
Adicionar Tag
Sem tags, seja o primeiro a adicionar uma tag!
|
| id |
riut-1-1620 |
|---|---|
| recordtype |
dspace |
| spelling |
riut-1-16202016-08-26T06:00:39Z Desempenho de fosfitos de potássio no manejo de mofo branco em soja Performance of potassium phosphite on white mold management in soybeans Camochena, Rubia Cristiani Santos, Idalmir dos http://lattes.cnpq.br/2601046635043330 Oliveira, Marisa de Cacia http://lattes.cnpq.br/6197941702252267 Reis, Erlei Melo Giaretta, Rosangela Dallemole Oliveira, Marisa de Cacia Santos, Idalmir Fungos Soja Fungi Soybean CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE Soybean plays an important role in the Brazilian agriculture being one of the products most exported by the country. Its yield may be affected by diseases such as white mold, caused by the fungus Sclerotinia sclerotiorum Lib. de Bary, which, under favorable field conditions prevents the crop of expressing all its productive potential. The fungus is cosmopolitan and infects more than 400 species of plants. This disease is difficult to control, and the use of chemicals has not been sufficient to avoid significant losses, thus, this products are expensive and may cause environmental damage. Alternative methods, such as foliar fertilizers based on potassium phosphite, can also be used in the management of this disease. In this context, this work aimed to study different sources of potassium phosphite and its effects in the control of white mold in soybeans, as well as the time of application in culture, its action in inducing plants defense responses and/or its influence over the seeds quality. The effect of phosphites, over the pathogen, was evaluated in vitro, on mycelial inhibition, the mass of dry mycelium and germination of sclerotia. In all tests, the following phosphites were utilized: Phosphite A (P2O5-40%; K2O-20% - 1 L/ha); Phosphite B (P2O5-40%; K2O-28% - 1 L/ha); Phosphite C (P2O5-40%; K2O-20% - 1 L/ha) e Phosphite D (P2O5-30%; K2O-20% - 2,4 L/ha). At the induction of resistance tests were evaluated the synthesis of phytoalexin in soybean cotyledons and the enzymes FAL and POX evaluated in seedlings in growing chamber, sprayed with phosphites and the fungicide fluazinam. Field experiment was carried out at Coronel Domingos Soares-PR, in the 2012/2013 season, in an area with natural infestation of the pathogen. Soybean cultivar BMX Active was no-till seeded with 0,5m between rows. The experimental was laid out as a factorial 5 x 4 scheme (treatment x application time). Phosphites sources were used, as described above, and water was sprayed in the control treatment. Treatments were applied at four different growth stages: V4, V4 + R1, R1 and R2 at the rates recommended by the manufacturer. Soybean yield components and seeds and health and physiological quality were evaluated after harvesting. None of the tested phosphites affected mycelial growth and sclerotia germination or influenced phytoalexin synthesis. Phosphites C and D stood out due to an increasing in the phenylalanine ammonia-lyase activity 48 hours after its inoculation. These same products also induced the synthesis and peroxidases and phosphite C kept the levels of this enzyme elevated up to 72 hours after inoculation. At the field trials, phosphites C and D stood out in the control of white mold. There was no significant interaction of potassium phosphite on physiological and sanitary quality of the seeds. CAPES A cultura da soja é importante no mercado brasileiro sendo um dos produtos mais exportados pelo país. Sua produtividade pode ser afetada pelas doenças, como mofo branco, causado pelo fungo Sclerotinia sclerotiorum Lib. de Bary, que, em condições ambientais favoráveis, se desenvolve nas lavouras e impede a cultura de expressar todo seu potencial produtivo. O fungo é cosmopolita e infecta mais de 400 espécies de plantas. Essa doença é de difícil controle, e o uso de agroquímicos não é suficiente para evitar perdas significativas, e além disso, causam danos ambientais e possuem custos elevados. Métodos alternativos, a exemplo dos fertilizantes foliares, à base de fosfito de potássio, também podem ser utilizados no manejo desta doença. Dessa forma, o objetivo do trabalho foi comparar diferentes fosfitos de potássio no controle do mofo branco em soja, bem como a época de aplicação na cultura, a ação na indução de respostas de defesa das plantas e/ou sua influência na qualidade das sementes. O efeito dos fosfitos sobre o patógeno foi avaliado, in vitro, sobre a inibição micelial, a massa de micélio seca e germinação de escleródios. Em todos os testes foram utilizados os seguintes fosfitos: Fosfito A (P2O5-40%; K2O-20% - 1 L/ha); Fosfito B (P2O5-40%; K2O-28% - 1 L/ha); Fosfito C (P2O5-40%; K2O-20% - 1 L/ha), Fosfito D (P2O5-30%; K2O-20% - 2,4 L/ha). Nos testes de indução de resistência foram avaliadas a síntese de fitoalexinas, em cotilédones de soja, e as enzimas FAL e POX, avaliadas em plântulas, em câmara de crescimento, pulverizadas com os fosfitos e o fungicida fluazinam. O experimento de campo foi conduzido no Município de Coronel Domingos Soares-PR, na safra 2012/2013, em área com infestação natural com o fitopatógeno. Foi semeada a cultivar de soja utilizada foi BMX Ativa, em sistema de semeadura direta, com espaçamento entre linhas de 0,5 m. O delineamento experimental foi em arranjo fatorial 5 x 4 (tratamentos x épocas de aplicação). Foram utilizados os fosfitos descritos acima e pulverização somente com água no tratamento testemunha. Os tratamentos foram aplicados em quatro estádios fenológicos da cultura: V4, V4+R1, R1 e R2, nas dosagens recomendadas pelo fabricante. Após a colheita foram avaliados componentes de rendimento e qualidade sanitária e fisiológica das sementes. Nenhum dos fosfitos testados afetou o crescimento micelial e a germinação dos escleródios, nem influenciou na síntese de fitoalexinas. Os fosfitos C e D se destacaram por aumentar a atividade da fenilalanina amonia-liase a partir de 48 horas após a inoculação. Esses mesmos produtos também induziram a síntese de peroxidases e o fosfito C foi o que manteve os níveis dessa enzima elevados até 72 horas após a inoculação. No experimento de campo os fosfitos C e D se destacaram no controle do mofo branco. Não houve interação significativa dos fosfitos de potássio na qualidade fisiológica e sanitária das sementes. 2016-08-25T21:22:34Z 2016-08-25T21:22:34Z 2015-12-10 doctoralThesis CAMOCHENA, Rubia Cristiani. Desempenho de fosfitos de potássio no manejo de mofo branco em soja. 2015. 79 f. Tese (Doutorado em Agronomia) - Universidade Tecnológica Federal do Paraná, Pato Branco, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1620 por openAccess application/pdf Universidade Tecnológica Federal do Paraná Pato Branco Brasil Programa de Pós-Graduação em Agronomia UTFPR |
| institution |
Universidade Tecnológica Federal do Paraná |
| collection |
RIUT |
| language |
Português |
| topic |
Fungos Soja Fungi Soybean CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE |
| spellingShingle |
Fungos Soja Fungi Soybean CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE Camochena, Rubia Cristiani Desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| description |
Soybean plays an important role in the Brazilian agriculture being one of the products most exported by the country. Its yield may be affected by diseases such as white mold, caused by the fungus Sclerotinia sclerotiorum Lib. de Bary, which, under favorable field conditions prevents the crop of expressing all its productive potential. The fungus is cosmopolitan and infects more than 400 species of plants. This disease is difficult to control, and the use of chemicals has not been sufficient to avoid significant losses, thus, this products are expensive and may cause environmental damage. Alternative methods, such as foliar fertilizers based on potassium phosphite, can also be used in the management of this disease. In this context, this work aimed to study different sources of potassium phosphite and its effects in the control of white mold in soybeans, as well as the time of application in culture, its action in inducing plants defense responses and/or its influence over the seeds quality. The effect of phosphites, over the pathogen, was evaluated in vitro, on mycelial inhibition, the mass of dry mycelium and germination of sclerotia. In all tests, the following phosphites were utilized: Phosphite A (P2O5-40%; K2O-20% - 1 L/ha); Phosphite B (P2O5-40%; K2O-28% - 1 L/ha); Phosphite C (P2O5-40%; K2O-20% - 1 L/ha) e Phosphite D (P2O5-30%; K2O-20% - 2,4 L/ha). At the induction of resistance tests were evaluated the synthesis of phytoalexin in soybean cotyledons and the enzymes FAL and POX evaluated in seedlings in growing chamber, sprayed with phosphites and the fungicide fluazinam. Field experiment was carried out at Coronel Domingos Soares-PR, in the 2012/2013 season, in an area with natural infestation of the pathogen. Soybean cultivar BMX Active was no-till seeded with 0,5m between rows. The experimental was laid out as a factorial 5 x 4 scheme (treatment x application time). Phosphites sources were used, as described above, and water was sprayed in the control treatment. Treatments were applied at four different growth stages: V4, V4 + R1, R1 and R2 at the rates recommended by the manufacturer. Soybean yield components and seeds and health and physiological quality were evaluated after harvesting. None of the tested phosphites affected mycelial growth and sclerotia germination or influenced phytoalexin synthesis. Phosphites C and D stood out due to an increasing in the phenylalanine ammonia-lyase activity 48 hours after its inoculation. These same products also induced the synthesis and peroxidases and phosphite C kept the levels of this enzyme elevated up to 72 hours after inoculation. At the field trials, phosphites C and D stood out in the control of white mold. There was no significant interaction of potassium phosphite on physiological and sanitary quality of the seeds. |
| format |
Tese |
| author |
Camochena, Rubia Cristiani |
| author_sort |
Camochena, Rubia Cristiani |
| title |
Desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| title_short |
Desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| title_full |
Desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| title_fullStr |
Desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| title_full_unstemmed |
Desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| title_sort |
desempenho de fosfitos de potássio no manejo de mofo branco em soja |
| publisher |
Universidade Tecnológica Federal do Paraná |
| publishDate |
2016 |
| citation |
CAMOCHENA, Rubia Cristiani. Desempenho de fosfitos de potássio no manejo de mofo branco em soja. 2015. 79 f. Tese (Doutorado em Agronomia) - Universidade Tecnológica Federal do Paraná, Pato Branco, 2015. |
| url |
http://repositorio.utfpr.edu.br/jspui/handle/1/1620 |
| _version_ |
1805313363382632448 |
| score |
10,814766 |