Impact of Heavy Metals on Non-food Herbaceous Crops and Prophylactic Role of Si

The presence of heavy metals in the environment is a direct consequence of anthropogenic activities, notably mining, industrialization and ever-increasing urbanization. Heavy metal toxicity is a major threat to plant productivity, because of the deleterious consequences, even at very low doses, on important processes, e.g. inhibition of photosynthesis, growth reduction and decreased biomass production, altered nutrient assimilation and premature senescence. Here, we will provide a survey on the impact of heavy metals on non-food herbaceous plants, in particular, energy and fibre crops (i.e. crops producing bast fibres, as well as seed trichomes). We will also examine the protective role of Si against heavy metal toxicity. Available high-throughput studies adopting –omics approaches are presented and discussed. The final paragraph highlighting the importance of coupling –omics to imaging techniques for the localization of the heavy metals in plant tissues concludes this survey.