Mechanisms And Control Effect Of Phosphite Against Phytophthora Infestans And Phytophthora Capsici

Phytophthora infestans cuases the potato late blight,one of the most serious plant diseases,and directly affects the growth potato and the related industry.Even until today,it remains as one of the main pathogens.Phytophthora capsici is a devastating pathogen of vegetable crops of national economic importance.The broad host range of Phytophthora capsici,makes it hard for the disease to be prevented and controlled effectively.In order to better control the disease and to further improve the control effect on Phytophthora infestans and Phytophthora capsici,we conducted this study by applying the inorganic compounds phosphite(phi),to protect plants from Oomycete infection,including the plate trials,greenhouse trials,lield trials,pathogenic detection,physiological indices etc.Both control effects and its mechanism were observed to confirm the inhibitory effect of phosphite on Phytophthora infestans and Phytophthora capsici.Through the data statistics and analysis,we found the spray of phosphite onto potato and pepper can reduce the Phytophthora infestans and Phytophthora capsici disease infection.It delayed the disease onset time and alleviated disease severity,therefore,enhanced the prevention effect.The phi could obviously inhibit the hyphal growth,zoospore germination and the biomass in planta.The application of phi caused obvious increase in expression of resistance related genes,including PR1,PR2,PR4,the enzyme activity of POD,SOD and CAT,and the total protein concentration.Taking together,we supposed that the phi may contol the oomycete disease by direct inhibition and induced host resistance.Our study will provide a basis in developing new disease control strategy caused by Phytophthora infestans and Phytophthora capsici.