**7.2 Se accumulation in plants**

Selenium are usually concentrated in younger leaves during the period of seedling and tend to accumulate in the vacuoles of plant cells and are discharged via sulfate transporters in the tonoplast [67–69]. Different categories of selenium accumulation exist in plants: non-accumulators, secondary accumulators and hyperaccumulators (**Figure 3**; [61]). The non-accumulators are plants that

#### **Figure 3.**

*Classification of plants based on selenium accumulation.*

accumulate lesser than 100 mgSe/Kg of their DW, cannot survive on selenium-rich soils and volatilize selenium in form of dimethylselenide (DMSe), for example, grasses [61]. The secondary accumulators show no sign of toxicity at 1000 mgSe/Kg DW, for example, *Camelina, Brassica napus.* Finally, the hyperaccumulators by their name accumulates greater amount of selenium (>1000 mgSe/Kg DW), flourish in selenium-rich areas of the world and they release selenium as dimethyldiselenide, such plants includes *Xylohiza* and *Conopis.*
