Effects of Host Characteristics, Elevation and Slope Direction on Severity of Beneh Rust (Pistacia mutica) in Firoozabad Forests, Iran

A field survey was carried out in Firoozabad Beneh (Pistacia mutica) Forest Station covering about 12000 hectares. Data were collected using combined random and systematic sampling methods to study the effect of altitude, dominant slope direction, sex and age of the host and plant canopy on rust severity caused by Pileolaria terebinthi. The rust severity decreased with plant age and elevations above 2000 meters. Female trees were more susceptible to the pathogen than males. The slope direction and plant canopy had no effect on disease severity. There was a significant correlation between plant age and elevation with disease severity but not with plant canopy. Regression analyses indicated a linear regression between disease severity variables and dependent variables of age, sex, and elevation.