The invention belongs to the field of nano material
biological effect research, and discloses a
magnesium-
nitrogen-
doped carbon dot, a preparation method thereof and application of the
magnesium-
nitrogen-
doped carbon dot in improvement of
plant photosynthesis. The preparation method comprises the following steps: dissolving
citric acid,
ethanolamine and
magnesium hydroxide in
ultrapure water, carrying out ultrasonic treatment, pouring the treated
system into a reaction kettle, and conducting reacting at 200 DEG C for 6 hours; after the reaction is finished, conducting cooling to
room temperature, filtering a product by using a filter head with the
pore diameter of 0.22 [mu]m, and then conducting dialyzing for 12 hours; and conducting freeze-
drying to obtain the magnesium-
nitrogen doped carbon dots. After the carbon dots are compounded with
chloroplast, the excitation energy can be absorbed by the
chloroplast for
photosynthesis, so that the photosynthetic activity is improved. After the carbon dots are applied to
rice plants through foliage spraying, Mg,N-CDs can be uniformly distributed in leaf cells, expression of related
enzyme genes is regulated and controlled, synthesis and
metabolism of
chlorophyll in leaves are promoted, the activity of
chlorophyll molecules is kept at a high level, and therefore the photosynthetic activity of the leaves is improved. Finally, the
plant growth is obviously improved.