Uptake of 134Cs by four species from the Asteraceae and two varieties from the Chenopodiaceae grown in two types of Chinese soil

This study investigated the uptake of 134Cs by Lactuca sativaL., Silybum marianumGaertn., Centaurea cyanusL., Carthamus tinctorius L. from the Asteraceae, and Beta vulgaris L. var. `Lutiancaiʹ and Beta vulgaris L. var. `Hongtiancaiʹ from the Chenopodiaceae grown in two widely-distributed soils (a paddy soil and a red soil) in South China. The results showed that the plants growing on the paddy soil had a relatively high yield and low [134Cs] while those growing on the red soil showed the opposite trend. The accumulation of 134Cs was dependent on plant species and soil types. For the paddy soil, mean values for [134Cs] were higher for the species of the Asteraceae (ranging from 165 to 185 Bq g^-1) than for those of the Chenopodiaceae (less than 140 Bq g^-1). For the red soil, S. marianumand C. cyanus of the Asteraceae had high average concentrations of 134Cs ranging from 340 to 400 Bq g^-1 but L. sativa and C. tinctorius from the same family had low concentrations of 134Cs ranging from 115 to 200 Bq g^-1 on a dry weight basis. B. vulgaris L. var. `Lutiancaiʹ and Beta vulgaris L. var. `Hongtiancaiʹ accumulated from 120 to 231 Bq 134Cs g^-1 of plant shoot. The transfer factor values of 134Cs for the studied species were in general higher in red soil than in paddy soil except C. tinctorius. All plant species from the Asteraceae family growing on the paddy soil had higher transfer factors than the B. vulgaris species. S. marianum, and C. cyanus growing on the red soil had TFs >1, being much higher than the B. vulgaris species. The results therefore showed that the plant species from the Asteraceae could accumulate higher concentrations of radiocesium than the Beta vulgaristhat has previously been suggested as a candidate for phytoremediation of radiocesium contaminated soils.