Effect of transpiration on Pb uptake by lettuce and on water soluble low molecular weight organic acids in rhizosphere

Does salicylic acid regulate antioxidant defense system, cell death, cadmium uptake and partitioning to acquire cadmium tolerance in rice?

“…A previous study with Indian mustard showed that Cd accumulation in shoots was strongly influenced by transpiration (Salt et al, 1995). Generally, transpiration is the most important mechanism for the uptake of nutrient elements (Novák and Vidovič, 2003;Tani and Barrington, 2005;Liao et al, 2006) by its gradient of water potential, which can drive them to move into roots and upward to shoots. This mechanism could be applicable to the Cd uptake pattern in the present study where more water loss from solution ( Figure 3A) along with lower Cd concentration in the solution ( Figure 3B) was observed in the +Cd compartment than in the W+Cd compartment during the 36-h-Cd exposure period.…”

Lead Uptake, Toxicity, and Detoxification in Plants

“…Transportation of metals from plant roots to shoots requires movement through the xylem (Verbruggen et al 2009) and, when it occurs, is probably driven by transpiration (Liao et al 2006). Arias et al (2010) demonstrated high lead deposition in xylem and phloem cells of mesquite plants by using X-ray mapping.…”

Nitric Oxide Increases Pb Tolerance by Lowering Pb Uptake and Translocation as well as Phytohormonal Changes in Cowpea (Vigna unguiculata (L.) Walp.)

“…In endodermis cells, the major part of lead is sequestered or excreted by plant detoxification systems (Pourrut et al 2011). Transportation of metals from plant roots to shoots requires movement through the xylem (Verbruggen et al 2009) and, when it occurs, is probably driven by transpiration (Liao et al 2006). Although in the present study, under lead stress conditions, just 50% of the total absorbed Pb by cowpea plants was maintained in the roots which indicates cowpea was sensitive to Pb but exogenous NO not only decreased total Pb uptake but also lowered translocation of Pb to aerial parts of plants.…”