There are several important aspects related to the evaluation of resistance in potato to Phytophthora infestans and we try to provide information on some of them here.

CIP LB protocol.  CIP is in the process of putting together a set of disease evaluation protocols.  This is a draft of the protocol for evaluation of LB resistance.

LB rating system.   There is a rating system with pictures at the Web site of Bill Fry that may be useful in evaluating disease severity. 

Disease Assessment.  A brief discussion of research done on factors that affect visual disease assessment.  Several good references.

R-gene differentials  A good source of information on the history and current availability of R-gene differentials often used in evaluatinng resistance.

Comparison of techniques.  A recent survey on evaluation methods for resistance to Phytophthora infestans that was published at the GILB'02 Conference. 

Measurement scales.   Here is a brief description of different types of measurement scales.  Something to keep in mind before measureing anything.

Follow links below for information on assessment of resistance using specific methodologies.

Field Evaluation

Whole Plant Evaluation in the Greenhouse

Detached Leaf Evaluation

Also see EUCABLIGHT Protocols, which include testing for tuber blight resistance.