Abstract:

To evaluate the anti-expansion capacity of different citrus germplasm against Diaporthe citri. In order to evaluate the anti-expansion capacity of 73 citrus germplasm，this study selected the in vitro citrus leaves and fruits to establish evaluation system. The resistance was evaluated with the methods of disease system clustering analysis，average diameter of the speckle and disease index method. The 73 citrus varieties were grouped into five groups：High resistant，medium resistant，resistant，susceptible and high susceptible varieties taken advantage of three analysis methods. Most of lemon and grapefruit varieties were highly resistant，sweet orange and Citrus reticulate was susceptible to D. citri.

Key words: citrus, Diaporthe citri, anti-expansion capacity