Data/hora: 06/06/2024 13:31:39

Provedor de dados: 	39	
País: 	Brazil	
Título: 	Seed vigor, antioxidant metabolism and initial growth characteristics of red rice seedlings under different light intensities	
Autores: 	Aumonde,Tiago Zanatta; Pedó,Tiago; Borella,Junior; Amarante,Luciano do; Villela,Francisco Amaral.	
Data: 	2013-06-01	
Ano: 	2013	
Palavras-chave: 	Oryza sativa L.; Shading; Chlorophyll content; Antioxidant enzymes.	
Resumo: 	This work aimed to evaluate the effect that different intensities of light have on the physiological attributes of red rice seeds and seedlings. Before and after emergence, seedlings were exposed to light levels of 35%; 65% and 100% in a greenhouse. We evaluated shoots and roots, in terms of length and dry mass, as well as leaf area and content of chlorophyll (a,b and total). In leaves and roots, we quantified the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and guaiacol peroxidase (POX). We determined the leaf area ratio (F A), leaf mass ratio (F W), specific leaf area (S A), and shoot/root ratio (P W). At higher light intensities, shoot length decreased, whereas root length, dry mass and number of tillers increased. Leaf area was greatest in seedlings exposed to a 65% light level. The F A, F W, S A and P W were lowest at a light intensity of 100%. Differences in light intensity had qualitative and quantitative effects on chlorophyll contents. The activity of SOD and CAT was higher at lower light levels, whereas the inverse was true for APX and POX activity. Extremes of light availability alter the activity of antioxidant enzymes, negatively affecting the initial growth characteristics and photosynthetic pigments of red rice seedlings.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000200007	
Editor: 	Sociedade Botânica do Brasil	
Relação: 	10.1590/S0102-33062013000200007	
Formato: 	text/html	
Fonte: 	Acta Botanica Brasilica  v.27 n.2 2013	
Fonte: 	info:eu-repo/semantics/openAccess