Data/hora: 01/06/2024 06:28:25

Biblioteca(s): | Embrapa Soja.
Data corrente: | 05/09/2007
Data da última atualização: | 21/07/2008
Autoria: | BORDIGNON, J. R.
Título: | Soybean responses to atmospheric increases in carbon dioxide (CO2) and ozone (O3).
Ano de publicação: | 2006
Fonte/Imprenta: | 2006.
Páginas: | 213 f.
Idioma: | Inglês
Notas: | Dissertation (Doctor in Philosophy in Food Science and Human Nutrition) - University of Illinois at Urbana-Champaing.
Conteúdo: | Atmospheric concentration of carbon dioxide (CO) has been increasing steadily since the industrial revolution and is expected to double by the middle of this century. Ozone (03), a secondary air pollutant, has become an issue in the last decades for its damaging effects on humans as well on animaIs and plants. The effects of elevated carbon dioxide ([CO2] = 550 µmol mol -¹ ozone ([03] = 1.2 x ambient) and their combination were evaluated in three soybean cultivars from maturation group (MG) II (Corsoy-79, Dwight and Loda) and three cultivars from MG III (Pana, Pioneer 93B15 and Williams), using a FACE (Free Air Concentration Enrichment) facility (www.soyface.uiuc.edu). Elevated [CO2] caused an improvement in final plant height and yield components (number of nodes, pods and seeds per plant; seed volume and seed weight), while elevated [03] had an opposite effect. Plants grown under elevated [CO2] alone or in combination with elevated [03] experienced also a delay in senescence and seeds of Loda and Pana demonstrated seed chlorophyll retention at harvest. No changes in seed N or fatty acid content were found due to treatment; however,variation among the years of evaluation was observed. Seed size was strongly correlated to seed C content but not to seed N. Total seed isoflavone content response to treatments was cultivardependent, with elevated [CO2] causing an increase in Dwight and Loda and elevated [03] causing a decrease in Corsoy and Loda. Isoflavone concentration also varied among the years of evaluation, indicating that other environmental factors influenced plant responses. A reduction in seed Ca and Zn content due to elevated [CO2] and an increase due to elevated [03] was observed in most cultivars evaluated. Results presented aIs o demonstrate that elevated [CO2] mitigates the damages caused by elevated [03].
Categoria do assunto: | --
Registro original: | Embrapa Soja (CNPSO)
Exemplares: | CNPSO - (27506-1) - ADD - TS - -- - 11/06 -  - 11/06 - DIS