A review of the evidence
Crop yields are increasingly under pressure from various climate-induced factors including drought.
A comprehensive review published in the Spanish Journal of Agricultural Research describes how nanomaterials can ameliorate the damaging effects of drought stress in horticultural and crop plants by regulating gene expression and altering physiological and biochemical processes.
Carbon-based nanoparticles, including carbon nanotubes (CNTs) and fullerene, have been shown to improve seed germination and plant growth, induce salinity tolerance, and increase chlorophyll index, total phenolics and antioxidant capacity under moderate drought stress. Both metallic and non-metallic nanoparticles have been used to ameliorate the effects of drought stress. Soil application of cerium oxide nanoparticles (nanoceria) can improve photosynthetic performance and water use efficiency, and soil-applied iron nanoparticles have been shown to decrease Cd concentrations in drought-stressed crops grown in Cd-contaminated soil. Seed treatment with nanopolymers such as nanochitosan and nanocomposite fertilizers can increase growth and yield under water stress. But not all treatments are favourable – some nanoparticle applications have negatively affected seed germination and seedling growth as a consequence of oxidative injury due to inactivation of various cellular antioxidant enzymes.
The review authors conclude that nanoparticles appear to act by regulating the expression of several genes involved in drought tolerance such as LEA (late embryogenesis abundant) and aquaporins, in addition to altering various physiological and biochemical processes, including alleviating oxidative stress damage by enhancing antioxidant defence systems, improving photosynthesis through increasing the content of photosynthetic pigments and RuBisCO activity, and enhancing uptake and translocation of water and nutrients by improving root growth and upregulation of aquaporins.
For research on treatments and effects of nanomaterials on drought stress, search:
(nanotechnology or nanoparticles or nanomaterials) and drought