Over expression of the Q-type ZFP StZFP2 in potato increases resistance to potato late blight (Phytophthora infestans) infection

ABSTRACTLate blight in potato caused by Phytophthora infestans remains a major impediment to potato growers worldwide. Utilization of regulators that affect defence may augment control measures to achieve a basal defence against late blight. This work examines the effect of over-expressing the transcription factor StZFP2 in potato on P. infestans infection. StZFP2 is induced upon infestation by chewing insects such as Manduca sexta and the pathogen P. infestans. StZFP2 was transformed into potato under the control of the CaMV 35S promoter. Three over-expressing lines (OE-StZFP2) resulted in significantly lower lesion size five days after infection (DAI). The increased expression of StZFP2 slowed the spread of infection at 5DAI. Levels of StZFP2 and classic pathogen response marker genes, StPR-1b and StPR-2 were significantly lower in more resistant lines, suggesting that OE-StZFP2 affects this pathogen response.