Data/hora: 13/06/2024 08:51:59

Provedor de dados: | 48
País: | Chile
Título: | Anatomical root variations in response to water deficit: wild and domesticated common bean (Phaseolus vulgaris L)
Autores: | Peña-Valdivia,Cecilia B; Sánchez-Urdaneta,Adriana B; Meza Rangel,Joel; Juárez Muñoz,Juana; García-Nava,Rodolfo; Celis Velázquez,Raquel.
Data: | 2010-01-01
Ano: | 2010
Palavras-chave: | Endodermis; Protoderm; Seedlings; Water potential; Xylem.
Resumo: | Root anatomical responses to water deficit are diverse and regulation of water uptake strongly depends on plant anatomy. The ancestors of common bean (Phaseolus vulgaris L.) cultivars are the wild common beans. Because wild beans adapt and survive well in theon atural environment, it is hypothesized that wild common bean roots are less affected than those of domesticated beans at low substrate water potential (&amp;#968;W). A wild common bean accession from Chihuahua Mexico and cv. Bayomex were studied. Seedlings with a mean root length between 3 and 4 cm were maintained for 24 h in vermiculite at &amp;#968;W of -0.03 (well hydrated), -0.65, -1.48 and -2.35 MPa (partially dry). Ten anatomical characteristics of differentiation and cell division in root regions were evaluated. Thickness of epidermis and protoderm diminished similarly in wild and domesticated beans growing at low substrate &amp;#968;W (between -0.65 and -2.35 MPa). At the same time, parenchymatic cell area diminished by 71 % in the domesticated variety, but by only 32 % in the wild bean at -2.35 MPa. Theon umber of cells in the cortex and the thickness of the xylem wall increased in both wild and domesticated beans at low substrate &amp;#968;W;on evertheless, the effect was significantly lower in the wild bean. Theon umber of xylem vessels increased in the cultivar (up to 40 %) while in the wild bean it decreased (up to 33 %). The diameter of xylem vessels and transverse root area diminished (15 and 57 %, respectively) in the cultivar, but in the wild common bean wereon ot affected. Anatomical root characteristics and their modifications in both differentiation and cell division in root regions demonstrated that the wild bean reacted quite differently to substrate &amp;#968;W than the domesticated common bean.
Tipo: | Journal article
Idioma: | Inglês
Identificador: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000400006
Editor: | Sociedad de Biología de Chile
Formato: | text/html
Fonte: | Biological Research  v.43 n.4 2010