Data/hora: 23/09/2024 23:05:28

Biblioteca(s): 	Embrapa Trigo.	
Data corrente: 	10/01/2010	
Data da última atualização: 	29/08/2011	
Autoria: 	NORVELL, W. A.; WELCH, R. M.	
Título: 	Growth and nutrient uptake by barley (Hordeum vulgare L. cv. Herta): Studies using on N- (2-Hydroxylthyl) ethylenedinitrilotriacetic acid-buffered nutrient solution technique. I. Zinc ion requirements.	
Ano de publicação: 	1993	
Fonte/Imprenta: 	Plant Physiology, v. 101, n. 2, p. 619-625. 1993.	
Idioma: 	Inglês	
Conteúdo: 	The critical range of Zn2+ activity in nutrient solution required for optimum growth of barley (Hordeum vulgare L. cv Herta) was studied using the synthetic chelating agent N-(2-hydroxyethyl)ethylenedinitrilotriacetic acid to buffer micronutrient metal ions. The activity of Zn2+ was varied over a wide range from approximately 0.1 x 10–)11 to 22 x 10–)11 M Zn2+. The dry weight of barley shoots reached a maximum at Zn2+ activities above approximately 3 x 10–)11 M and was clearly depressed when Zn2+ activities were below about 1 x 10–)11 M. The relationship in shoots between dry weight and Zn concentrations supports the view that there is a critical Zn concentration of about 25 [mu]g g-1 dry weight in whole shoots of barley seedlings. When Zn2+ activities in solution were near or below approximately 3 x 10–)11 M, barley shoots accumulated higher concentrations of P, Mn, Ca, Mg, and Na, whereas Cu concentrations were reduced. P and Mn began to accumulate in the shoots before differences in dry weights were apparent and provided the earliest index of Zn deficiency. In Zn-deficient roots, concentrations of Ca and Mg increased by 25 to 30%, and those of Fe and Mn more than doubled. Zn appears to play a special role in regulating uptake of several mineral nutrients in barley.	
Thesagro: 	Cevada; Crescimento; Nutriente.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Trigo (CNPT)	
Exemplares: 	CNPT - (27566-1) - ADD - SP - -- - 13647 -  - 13647 - DIS