Effects of organic fertilizer application on soil fertility and leaf nutrients and fruit quality of citrus

In order to improve the fruit quality and yield of citrus in Chongming County of Shanghai, the effects of organic fertilizer rate and depth of manuring on soil fertility,and leaf nutrients and fruit quality of citrus were investigated.The results showed that in comparison with no application of organic fertilizer(CK),application of organic fertilizer could increase the readily available N,available P and available K contents of soil,and the contents in the best fertilizer treatment were respectively 20.9%,24.9%and 44.4%higher than those in CK;application of organic fertilizer could also increase the organic matter content of soil by 16.2%in the best fertilizer treatment,and decrease the bulk density and pH of the soil,thus improving the soil fertility.In addition,application of organic fertilizer could increase the quantity of soil microorganism and the total N and total K contents in citrus leaves and improve the fruit quality of citrus.