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| Author(s): |
Tereza Cristina de Carvalho
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Piracicaba. |
| Institution: | Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) |
| Defense date: | 2009-08-07 |
| Examining board members: |
Ana Dionisia da Luz Coelho Novembre;
Silvio Moure Cicero;
Francisco Carlos Krzyzanowski
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| Advisor: | Ana Dionisia da Luz Coelho Novembre |
| Abstract | |
Mechanical damages, with immediate and latent effects, are characterized to cause problems in soybean seed production. The goal of this research was to verify the occurrence of mechanical damages with X-rays in soybean seeds harvested with different levels of seed moisture content, determining the possible alterations in seeds physiological potential caused by physical injuries, right after the harvest and after six months of storage, and to compare the use of X-rays with the use of sodium hypochlorite and tetrazolium tests to detect the occurrence of different levels of mechanical damages in these seeds. The soybean seeds were from cultivars Embrapa 48 and FTS Águia, which have differences in lignin content in seed coat. The seeds were produced and harvested by hand and mechanically with the moisture contents of 18%, 15% and 12%, and were evaluated according to their seed moisture content and mechanical damages immediately after the harvest. After drying, seed quality was determined by germination, seedling emergence, tetrazolium (viability and vigor), accelerated aging, sodium hypochlorite and sanity tests. After the initial evaluation, the seeds were kept in storage conditions (20°C and 45% RAH) and analyzed after six months. The results indicated that the use of X-rays allows the identification of mechanical damages with immediate effects in the soybean seeds, cultivars Embrapa 48 and FTS Águia, but damages with latent effects were not identified; seed physiological potential is affected by harvesting method and seed moisture content; Xray method does not have the same efficiency as sodium hypochlorite and tetrazolium tests to determine seed mechanical damages in the soybean seed. (AU) | |