Obstacles of pollution from Hg on P absorption by citrus plants.

Main barrier factors in P absorption by citrus plants were screened by collecting leaves and soil samples in the large area of citrus-producing area,and making correlation analysis on data of chemical analysis.It was validated that pollution from Hg in leaf was the main influencing factors of P absorption by citrus plants,by screening 250 data of 3 citrus varieties for 2 years.Leaf Hg content was higher than soil Hg content and the correlation between them was not significant.In randomly checked 12 fungicides,Cu contents in 6 fungicides were over 0.5 mg·kg-1,the highest content was 15.1 mg·kg-1,As a result,fungicide is Hg pollution resource in citrus orchard.