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Registro Completo |
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Biblioteca(s): |
Embrapa Cerrados; Embrapa Trigo. |
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Data corrente: |
18/12/1995 |
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Data da última atualização: |
14/01/2000 |
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Autoria: |
NASSER, L. C. B. |
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Título: |
Studies on microorganisms carried by cereal seeds produced in Brazil and Washington: their influence on seedling vigor, chemical and biological control, and histology of Septoria nodorum (Berk.) Berk. on wheat seed. |
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Ano de publicação: |
1983 |
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Fonte/Imprenta: |
[Pullman]: Washington State University, 1983. |
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Páginas: |
195p. |
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Idioma: |
Inglês |
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Notas: |
Ph.D. Dissertation. |
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Conteúdo: |
Four hundred kernels of each of 82 imported seed lots were plated on each of three cultural media for the purpose of establishing the sanitary status of cereal seed produced in Brazil. The media were somewhat differential in revealing microorganisms. Of 32,800 seeds plated on potato-dextrose agar, 17,783 yieded a fungus colony. Alternaria spp. and Drechslera spp. were among the most frequently isolated fungi. The blotter method tended to favor the emergence of Cladosporium spp. and Drechslera ssp., while oxgall agar medium permitted the development of Septora nodorum, Fusarium spp. and Pseudomonas syringae. In general, Brazil-grown seed was heavily laden with pathogens. Barley, with an infection level of 50.5 percent, was more infested than triticale (43.3 percent) or wheat (26.6 percent). Of undoubted significance was the fact that 88 percent of the seed lots were infected with Drechslera; 59percent with Fusarium and 52 with S. nodorum. Seeds produced in Brazil had lower germination, lower emergence rate indices, and a higher rate of pathogen transmission to emerging seedlings than counterpart seeds produced in Pullman. Cereal seed produced in Pullman was virtually free of pathogens, indicating an inability of most organisms to persist from one host generation to the next in the dry climate attending crop maturation at Pullman. However, it was revealed for the first time that wheat seed produced under moist conditions of western Washington was sometimes infected with S. nodorum and Pseudomonas syringae. The seedborne phase of S. nodorum was controlled by benomyl when used alone or in combination with thiram or captan. Several isolates of P. syringae were antagonistic to S. nodorum. Septoria nodorum was found to penetrate wheat seed coats only as deeply as the testa layer. There is a strong probability that cereal yields in Brazil would be increased by reducing the amount of seeborne pathogens. MenosFour hundred kernels of each of 82 imported seed lots were plated on each of three cultural media for the purpose of establishing the sanitary status of cereal seed produced in Brazil. The media were somewhat differential in revealing microorganisms. Of 32,800 seeds plated on potato-dextrose agar, 17,783 yieded a fungus colony. Alternaria spp. and Drechslera spp. were among the most frequently isolated fungi. The blotter method tended to favor the emergence of Cladosporium spp. and Drechslera ssp., while oxgall agar medium permitted the development of Septora nodorum, Fusarium spp. and Pseudomonas syringae. In general, Brazil-grown seed was heavily laden with pathogens. Barley, with an infection level of 50.5 percent, was more infested than triticale (43.3 percent) or wheat (26.6 percent). Of undoubted significance was the fact that 88 percent of the seed lots were infected with Drechslera; 59percent with Fusarium and 52 with S. nodorum. Seeds produced in Brazil had lower germination, lower emergence rate indices, and a higher rate of pathogen transmission to emerging seedlings than counterpart seeds produced in Pullman. Cereal seed produced in Pullman was virtually free of pathogens, indicating an inability of most organisms to persist from one host generation to the next in the dry climate attending crop maturation at Pullman. However, it was revealed for the first time that wheat seed produced under moist conditions of western Washington was sometimes infected with S. nod... Mostrar Tudo |
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Palavras-Chave: |
Brasil; Estados Unidos; Fungal diseases; Seed; Seed longevity; Washington; Wheats. |
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Thesagro: |
Controle Biológico; Controle Químico; Doença; Doença Fúngica; Fungo; Fusariose; Fusarium; Histologia; Microrganismo; Semente; Septoria Nodorum; Trigo; Triticum Aestivum. |
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Thesaurus Nal: |
biological control; Brazil; chemical control; Drechslera; fungi; plant tissues; United States; vigor. |
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Categoria do assunto: |
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Marc: |
LEADER 03230nam a2200469 a 4500
001 1563860
005 2000-01-14
008 1983 bl uuuu m 00u1 u #d
100 1 $aNASSER, L. C. B.
245 $aStudies on microorganisms carried by cereal seeds produced in Brazil and Washington$btheir influence on seedling vigor, chemical and biological control, and histology of Septoria nodorum (Berk.) Berk. on wheat seed.
260 $a[Pullman]: Washington State University$c1983
300 $a195p.
500 $aPh.D. Dissertation.
520 $aFour hundred kernels of each of 82 imported seed lots were plated on each of three cultural media for the purpose of establishing the sanitary status of cereal seed produced in Brazil. The media were somewhat differential in revealing microorganisms. Of 32,800 seeds plated on potato-dextrose agar, 17,783 yieded a fungus colony. Alternaria spp. and Drechslera spp. were among the most frequently isolated fungi. The blotter method tended to favor the emergence of Cladosporium spp. and Drechslera ssp., while oxgall agar medium permitted the development of Septora nodorum, Fusarium spp. and Pseudomonas syringae. In general, Brazil-grown seed was heavily laden with pathogens. Barley, with an infection level of 50.5 percent, was more infested than triticale (43.3 percent) or wheat (26.6 percent). Of undoubted significance was the fact that 88 percent of the seed lots were infected with Drechslera; 59percent with Fusarium and 52 with S. nodorum. Seeds produced in Brazil had lower germination, lower emergence rate indices, and a higher rate of pathogen transmission to emerging seedlings than counterpart seeds produced in Pullman. Cereal seed produced in Pullman was virtually free of pathogens, indicating an inability of most organisms to persist from one host generation to the next in the dry climate attending crop maturation at Pullman. However, it was revealed for the first time that wheat seed produced under moist conditions of western Washington was sometimes infected with S. nodorum and Pseudomonas syringae. The seedborne phase of S. nodorum was controlled by benomyl when used alone or in combination with thiram or captan. Several isolates of P. syringae were antagonistic to S. nodorum. Septoria nodorum was found to penetrate wheat seed coats only as deeply as the testa layer. There is a strong probability that cereal yields in Brazil would be increased by reducing the amount of seeborne pathogens.
650 $abiological control
650 $aBrazil
650 $achemical control
650 $aDrechslera
650 $afungi
650 $aplant tissues
650 $aUnited States
650 $avigor
650 $aControle Biológico
650 $aControle Químico
650 $aDoença
650 $aDoença Fúngica
650 $aFungo
650 $aFusariose
650 $aFusarium
650 $aHistologia
650 $aMicrorganismo
650 $aSemente
650 $aSeptoria Nodorum
650 $aTrigo
650 $aTriticum Aestivum
653 $aBrasil
653 $aEstados Unidos
653 $aFungal diseases
653 $aSeed
653 $aSeed longevity
653 $aWashington
653 $aWheats
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Registro original: |
Embrapa Cerrados (CPAC) |
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