Correlation of toxicity with lead content in root tip cells (Allium cepa L.).
The present study determines lead content in onion root tip cells (Allium cepa L.), correlating it with its toxicity. The treatment was carried at 25 +/- 0.5 degrees C using aqueous solutions of lead chloride at 0.1, 0.25, 0.50, 0.75, and 1 ppm for 12, 24, 48, and 72 h. For each treatment, a control where the lead solution was substituted by distilled water was included. After treatment, the meristems were fixed with a mixture of alcohol-acetic acid (3:1) and colored according to the technique of Feulgen. Lead content was quantified by graphite furnace absorption atomic spectrometry. The lead content in the roots ranged from 3.25 to 244.72 microg/g dry weight, with a direct relation with the concentration and time of exposure. A significant negative correlation was presented (r = -0.3629; p < 0.01) among lead content and root growth increment, and a positive correlation (r = 0.7750; p < 0.01) with the induction of chromosomic aberrations. In conclusion, lead is able to induce a toxic effect in the exposed roots, correlated with its content.
Carruyo
Ingrid
I
Departamento de Biología, Facultad Experimental de Ciencias, Universidad del Zulia, Maracaibo, Estado Zulia, Venezuela. yncarr24@hotmail.com
Fernández
Yusmary
Y
Marcano
Letty
L
Montiel
Xiomara
X
Torrealba
Zaida
Z
D002869:Chromosome Aberrations / Q000139:chemically induced; D007854:Lead / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity*; D018519:Meristem / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D008938:Mitosis / Q000187:drug effects*; D008940:Mitotic Index; D019697:Onions / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism
D007854:Lead; C029891:lead chloride