Relationship between Early Blight Disease Severity and Uptake of NPK by Potato Under Diverse Fertility Gradient of Soil

Abstract

Negative correlations were observed between the early blight disease severity (%) and uptake of Nitrogen, Phosphorus and Potassium by potato crop. The experiment was carried out by 13 treatments combination including untreated control (S0N0P0K0) with four different soil fertility gradient and Kufri jyoti was selected as test variety for the experiment. From this relationship, it clearly indicated that with increasing the disease severity there was Nitrogen uptake drastically reduced. Similarly, in case of Phosphorus and Potassium uptake by the plant extremely reduced with the increases of early blight disease severity. It due to less leaf area index (LAI), less root formation and less photosynthetic production were confirmed in the linear regression line and regression equations. The highest tuber yield (340.4 quintal ha-1) was recorded in high fertility gradient of soil with higher NPK combinations (S4N250P150K125) followed by medium fertility gradient soil i.e. 339.4 quintal ha−1 (S3N200P150K125) and were found significantly superior to other treatments combination and in respect of untreated control under different fertility gradient of soil. From this observation, it could be noted that the high fertility gradient soil recorded the maximum yield and minimum yield obtained in low fertility gradient of soil. So it revealed that the nutrition factors as well as disease severity strongly interfere in the tuber yield.