Ciencia del suelo
versión On-line ISSN 1850-2067
BONGIOVANNI, Marcos Darío y LOBARTINI, Juan Carlos. Effect of soluble soil organic substances on iron absorption by sunflower seedlings. Cienc. suelo [online]. 2009, vol.27, n.2, pp. 171-176. ISSN 1850-2067.
Soil organic matter (SOM) is one of the most important natural resources that affect soil quality. Soil uses and management may decrease SOM content affecting physical and chemical soil properties and consequently plant growth. The aim of this study was to evaluate the effect of soluble organic carbon (SOC) and fulvic acids (FA), both affected by tillage, on iron uptake by sunflower seedlings. Soluble organic carbon disappeared in the soil under cultivation and FA was reduced 57%. Sunflower seedlings growing in hydroponic solution increased iron absorption and translocation. Thus, iron content in leaves increased 18.1 and 6.7 times with the addition of 30 mg L-1 and 40 mg L-1 of SOC and FA, respectively. Increasing SOC and FA concentration in nutrient solution improved iron uptake and also prevented iron precipitation in roots.
Palabras clave : Humic substances; Iron uptake; Fulvic acid.