The invention provides a
rotation method for reducing morbidity of root-knot nematodes, which comprises the following steps: planting waltheria indica: preparing soil,
sowing waltheria indica in the middle of a furrow
bed, covering soil, and spraying water until the furrow
bed is infiltrated until the waltheria indica is harvested; one month before the tobacco seedlings are transplanted, the harvested waltheria indica is used as waltheria indica
fertilizer, deep ploughing is carried out, the tobacco seedlings are transplanted,
topping is carried out, leaves are reserved, and tobacco leaves are harvested. The waltheria indica and the tobacco are subjected to
crop rotation, the waltheria indica
fertilizer prepared from the waltheria indica, the
edible mushroom residues and the black
fungus fermentation liquor is applied in combination with planting of the waltheria indica, the two
modes cooperate with each other, the soil microbial
community structure is adjusted, the
soil organic matter content is improved, the good prevention and
control effect on the root-knot
nematode is achieved, and the prevention and
control effect can reach 88%; the harvested tobacco leaves are light in
membrane lipid peroxidation degree, growth and development of tobacco plants are promoted, accumulation of substances contained in the tobacco leaves is improved, and the quality of the tobacco leaves is good.