Graphene oxide exhibited positive effects on the growth of Aloe vera L

There is increasing evidence for graphene associated plant growth promotion, however, the chronic effects of soil-applied graphene remain largely unexplored. The present study investigated the morphological, physiological and biochemical responses of graphene oxide (GO) on Aloe vera L. over the concentration range of 0-100 mg/L for four months. Our results demonstrated that GO, with the best efficiency at 50 mg/L, could enhance the photosynthetic capacity of leaves, increase the yield and morphological characters of root and leaf, improve the nutrient (protein and amino acid) contents of leaf, without reducing the content of the main bioactive compound aloin. Compared with leaves, the effect of GO on root growth was more obvious. Although the electrolyte leakage and MDA content were raised at high concentrations, GO treatment did not increase the root antioxidant enzymes activity or decrease the root vigor, which excluding typical stress response. Furthermore, injection experiments showed that the GO in vivo did not change the plant growth state obviously. Taken together, our study revealed the role of GO in promoting Aloe vera growth by stimulating root growth and photosynthesis, which would provide theory basis for GO application in agriculture and forestry.

Automated summary

The study found that graphene oxide (GO) promotes the growth of Aloe vera by stimulating root growth and photosynthesis, with the best efficiency observed at a concentration of 50 mg/L. GO enhanced the photosynthetic capacity of leaves, increased yield, morphological characters, and nutrient contents of leaves without reducing the bioactive compound aloin. Despite increased electrolyte leakage and MDA content at high concentrations, GO treatment did not affect root antioxidant enzymes activity or root vigor, suggesting a non-typical stress response.