Iodine uptake by spinach (Spinacia oleracea L.) plants grown in solution culture: effects of iodine species and solution concentrations

Abstract

A hydroponic experiment was carried out to investigate the effects of iodine species and solution concentrations on iodine uptake by spinach (Spinacia oleracea L.). Five iodine concentrations (0, 1, 10, 50 and 100 AM) for iodate (IO 3 À ) and iodide (I À ) were used. Results show that higher concentrations of I À ( R 10 AM) had some detrimental effect on plant growth, while IO 3 À had little effect on the biomass production of spinach plants. Increases in iodine concentration in the growth solution significantly enhanced I concentrations in plant tissues. The detrimental effect of I À on plant growth was probably due to the excessively high accumulation of I in plant tissues. The solution-tospinach leaf transfer factors (TF leaf , fresh weight basis) for plants treated with iodide were between 14.2 and 20.7 at different solution concentrations of iodide; TF leaf for plants treated with iodate decreased gradually from 23.7 to 2.2 with increasing solution concentrations of iodate. The distribution coefficients (DCs) of I between leaves and roots were constantly higher for plants treated with iodate than those treated with iodide. DCs for plants treated with iodide increased with increasing solution concentrations of iodide, while DCs for plants treated with iodate (around 5.5) were similar across the range of solution concentrations of iodate used in this experiment. The implications of iodine accumulation in leafy vegetables in human iodine nutrition are also discussed. D

Interactions between selenium and iodine uptake by spinach (Spinacia oleracea L.) in solution culture

“…It has been shown that Se can be easily translocated from roots to shoots if plants are fed with selenate (Zayed et al, 1998). The DC values for Se obtained in this study are comparable to those reported by Zayed et al (1998), and the DC values for I are comparable to those we reported earlier in solution culture (Zhu et al, 2003). In this study the concentrations of Se and I in the growth solution were much higher than would be conventionally found in arable soils.…”

Biofortificación con yodo en plantas para consumo humano

“…No se considera al yodo como un elemento esencial para las plantas terrestres, aunque diversos estudios demostraron que estas absorben y acumulan yodo (Mackowiak y Grossl, 1999;Zhu et al, 2003). Esta aparente no esencialidad explica el porque el yodo no se contempla en los programas de…”

“…Iodine is not considered as an essential element for terrestrial plants, although several studies showed that these absorb and accumulate iodine (Mackowiak and Grossl, 1999;Zhu et al, 2003). This apparent non-essentiality explains why iodine is not contemplated in mineral fertilization programs of crops, despite the fact that it has been shown that the contribution of inorganic iodine salts can increase stress tolerance in plants (Leyva et al, 2011;Gupta et al, 2015).…”

Inter-Taxa Differences in Iodine Uptake by Plants: Implications for Food Quality and Contamination

“…Iodine (I) is readily taken up by plants if available [1], which is important to both agronomy and radioecology because, although I is not an essential element for plants, food crops are a major conduit for the entry of I to human foodchains. Stable I ( 127 I) is an essential trace element for humans whilst the radioisotopes 131 I and 129 I can be significant radioactive contaminants of the environment [2].…”

“…In many soils I − and IO3 − are the most common ionic forms, with I − most likely to be taken up by plants [1] because they have substantial capacity for the uptake of the chemically similar Cl − [9]. Overall, although soil-to-plant transfer factors can be quite low from, for example, Andosols with high anion exchange capacities [10], hydroponic experiments show that plants can take up large quantities of I if it is available to them [1] and most soils produce transfers to crops that can contribute significantly to food I content and to radiocontamination if 127 I or 131/129 I are available in the soil.…”