The great progress has been achieved in R gene clone recent years. Several potato late blight R genes
have been cloned at present and particularly we discovered that R3 has multiple allelic versions to allow
allele-mining [25]. It is reported that some R genes have been cloned, such as R1 [26]and R3a [25]genes
derived from S. demissum and the RB/Rpi-blb1 [27-28] and Rpi-blb2[29]genes from S. bulbocastanum.
These cloned R genes provide the starting point to develop R-gene polyculture. Other R genes were
mapped to different loci of chromosome. It is a good time now to develop R gene polyculture for potato
late blight control.