TABLE 1.

Identification criteria for late blight tolerance of potato leaves in vitro.

Grade of disease	Type	Degree of morbidity
1	Most tolerance	The lesion area is less than 3% or asymptomatic
2	More tolerance	The area of the lesion was 3–10%, forming an anaphylactic necrotic spot without chlorotic halo
3	Moderately tolerance	The area of the lesion was 10–30%. The lesion was water-soaked and surrounded by chlorotic halo. White mycelium could be seen on the surface of the lesion
4	Moderately susceptible	The lesion area ranged from 30 to 60%, there was an obvious chlorotic ring and white mold layer around the lesion
5	More susceptible	The lesion area was more than 60%, and a large number of white molds appeared on the lesion surface