The invention relates to a method for applying a
phosphate fertilizer to reduce the content of mercury in rice grains of a heavy mercury polluted rice field, belonging to the technical field of agricultural product heavy
metal pollution prevention and treatment. The method is characterized by comprising the following steps: in the heavy mercury polluted rice field (the soil Hg concentration is 2mg / kg, which is 4 times the national limit standard), applying 100kg / hm<2> (at a middle
phosphorus application level by an effective component P2O5) of the
phosphate fertilizer for three times, namely, applying 1 / 2 of the total phosphatic
fertilizer 3 days before rice
transplanting, and applying 1 / 4 of the total phosphatic fertilizer 5 days before earing and 10 days after head
sprouting respectively; throwing the
phosphate fertilizer 3 days before rice
transplanting, namely, uniformly throwing the
phosphate fertilizer into the rice field; applying the
phosphate fertilizer in a leaf surface spraying mode 5 days before earing and 10 days after head
sprouting, dissolving a water-soluble
phosphate fertilizer into water, and spraying 300L of water with the phosphate fertilizer to each
hectare of the rice field. Compared with a common high-level one-time phosphate fertilizer application method used in practical rice production, the method has an application effect that the content of mercury in the rice grains can be greatly reduced (the content of the mercury in indica type rice is reduced by 61.54%, and the content of mercury in
japonica rice is reduced by 56.67%), and the yield of rice is not greatly reduced.