Data/hora: 23/06/2024 01:19:27

Biblioteca(s): | Embrapa Soja.
Data corrente: | 06/04/2004
Data da última atualização: | 27/07/2007
Autoria: | BONINI, E. A.; FERRARESE, M. L. L.; CAPELETI, I.; KRZYZANOWSKI, F. C.; FERRARESE FILHO, O.
Título: | Lignin content and peroxidase activity in seed coat of soybean (Glycine max (L.) Merrill) susceptible and resistant to mechanical damage.
Ano de publicação: | 2004
Fonte/Imprenta: | In: WORLD SOYBEAN RESEARCH CONFERENCE, 7.; INTERNATIONAL SOYBEAN PROCESSING AND UTILIZATION CONFERENCE, 4.; CONGRESSO BRASILEIRO DE SOJA, 3., 2004, Foz do Iguassu. Abstracts of contributed papers and posters. Londrina: Embrapa Soybean, 2004.
Páginas: | p. 237.
Série: | (Embrapa Soja. Documentos, 228).
Idioma: | Inglês
Notas: | Editado por Flávio Moscardi, Clara Beatriz Hoffmann-Campo, Odilon Ferreira Saraiva, Paulo Roberto Galerani, Francisco Carlos Krzyzanowski, Mercedes Concordia Carrão-Panizzi.
Conteúdo: | Soybean seed coat is very thin and low in lignin content, and provides little protection to the fragile radicle, which lies in a vulnerable position directly beneath the seed coat. Due to this fact, mechanical damage is one of the causes of great loss of seed quality of soybean at harvest and processing. In this aspect, the occurrence of genetic variability for seed resistance to mechanical damage among different soybean cultivars was demonstrated. Based on the pendulum test, researchers of the Embrapa Soja classified 12 field grown soybean cultivars as follows: susceptible (Savana, Paranagoiana, IAC-2 and Davis), moderately resistant (Santa Rosa, IAC-8; Bossier and FT-10) and resistant (Doko, FT-2, Paraná and IAS-5). There is considerable interest in the lignin since its deposition in the seed coat tissue provides mechanical resistance and also protects the cell against microorganisms. The seed coat lignin content was found to be high in soybean cultivars with high index of resistance against mechanical damage. In addition to lignin, peroxidases have been suggested to be involved in various metabolic steps such as the formation of isodi-Tyr bridges in the cross-linking of cell wall proteins, the cross-linking of pectin by ferulic bridges, and the oxidation of cinnamyl alcohols prior to their polymerization during lignin and suberin formation. Seed coats tissues may accumulate large amounts of peroxidase in the hourglass cells of the sub-epidermis and may represent at least 5% of the protein in the dry seed coat. The function of peroxidases in the seed tissue is still not well understood and, consequently, the aim of the present work was to analyze the lignin contents and peroxidases activities of six soybean cultivars and its relationships with the mechanical damage. Seeds of six soybean cultivars (Doko, Paraná, Santa Rosa, FT-10, Savana and Paranagoiana) were evaluated by spectrophotometric methods to lignin content (l = 280 nm) and peroxidase (l = 470 nm). The results showed that the lignin content and peroxidase activity in the seed coat significantly differed among the soybean cultivars. The cultivars Doko and Paraná had the highest contents of lignin and peroxidase activities while Savana and Paranagoiana had the lowest lignin contents and enzymatic activities. Relationships between lignin content or peroxidase activity and the resistance to mechanical damage were observed. In conclusion, the lignin content and the peroxidase activity may be proposed as reasonable indicators of resistance to mechanical damage for soybean seeds.
Categoria do assunto: | --
Registro original: | Embrapa Soja (CNPSO)
Exemplares: | CNPSO - (23748-1) - UMT - PL - -- - RF 633.34072 - W927a -  - DIS