Data/hora: 15/05/2024 11:06:01

Provedor de dados: 	48	
País: 	Chile	
Título: 	Effects of substrate water potential in root growth of Agave salmiana Otto ex Salm-Dyck seedlings	
Autores: 	PEÑA-VALDIVIA,CECILIA B; SÁNCHEZ-URDANETA,ADRIANA B.	
Data: 	2009-01-01	
Ano: 	2009	
Palavras-chave: 	Maguey; Proline; Root anatomy; Root growth; Water deficit; Water stress.	
Resumo: 	The objective of this study was to test the hypothesis that root of maguey (Agave salmiana Otto ex Salm-Dyck) seedlings reacts during the first 24 h to low substrate water potential (Yw), by anatomical modifications. Three-4 cm root length seedlings were planted in vermiculite for 24 h at Yw between -0.03 and -2.35 MPa. Root dimensions, proline content and anatomy were evaluated. Substrate &amp;#968;w between -0.65 and -2.35 MPa did not significantly affect longitudinal root growth. However, proline content significantly increased from 1.6 to 2.1 emoles mg-1. Significant reductions of transverse root area (41 %), thickness of mucilage covering the epidermis (47 %), thickness of epidermis (between 15 and 46 %), area of the parenchyma (between 35 and 41 %) and number of vessels (up to 28 %) were observed with Yw of -2.35 MPa. In contrast, thickness of xylem wall, diameter of xylem vessels and the number of cells of the cortex of the differentiation root region significantly increased (64, 17, and 97 %, respectively). The anatomical changes associated with low substrate Yw indicate a net increase of root apoplatic paths; structures involved in water conduction increased their diameter under low substrate Yw conditions and anatomical changes occurred during the first 24 h of water stress.	
Tipo: 	Journal article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602009000200013	
Editor: 	Sociedad de Biología de Chile	
Formato: 	text/html	
Fonte: 	Biological Research  v.42 n.2 2009