关键词: 马铃薯 晚疫病 抗病基因近等混合系

Abstract:

Abstract： Potato （Solanum tuberosum L. ） is the fourth most important crop in the world and one of the top seven important crops in china. Late blight is a devastating disease of potato caused by Phytophthora infestans （Mont.） de Bary, which was the reason of the Great Irish Famine in 1 845. Todaay, late blight remains the No. 1 threat to potato production. It is urgent to improve the late blight resistance of potato cuhivars. Potato breeding for late blight resistance was one of the earliest practices mankind used to combat plant pathogens by means of genetic improvement, but the disease has not been controlled by resistance breeding so far. Resistance genes （R genes） introgressed from wild species broke down quickly. The potato-P, infestanns pathosystem suits the gene-for-gene model, which states that resistance only occurs when the R genes in the host and the corresponding avirulence gene （Avr） are both present and expressed. P. infestans ranks highest in the evolutionary potential and it can easily mutate its Avr genes and thus overccome the only promising solution for late blight control is potato plants carrying corresponding R genes. So, to release several R genes simultaneously and to artificially create a resistance polymorphism in the field, a strategy so called R gene polyculture. Recently, scientists gained a great success in cloning R genes conferring late blight resistance, providing a basis to create R gene polycuhure by means of transgenic technology.

Key words: potato, late blight, R gene polycuhure