Abstract: The pomegranate wilt is a kind of new plant disease occurred in Mengzi County of Yunnan Province and is aggravating in recent years. General field investigation, sample collection, vision analysis, and experts consultation on the disease were carried out on total of 240 pomegranate trees in 5 orchards during two growing seasons. Based on the data collected on emergence and symptoms of pomegranate wilt, the authors proposed a severity scale system of the disease according to the ratio (R) of the spread of wilt in trunk base to the width of trunk base. The system contains nine grades in disease severity. This system is useful to selection of disease-resistance pomegranate species and evaluation of protective reagents against the wilt in field trials.

Key words: wilt of pomegranate, disease severity, classification standard