Muraleedharan Nair, VBhuvanandran, DKAU2020-06-082020-06-081987http://krishikosh.egranth.ac.in/handle/1/5810147278PGAn investigation was conducted in the upland soils of Banana nursery, Peringammala to study the comparative performance of four sweet potato varieties under different levels and times of nitrogen and potassium application. The treatments consisted of three levels of nitrogen (50, 75 and 100 kg N/ha) and three levels of potassium (50,75 and 100kg K2O/ha) at two times of application. Four varieties (Cross-5, H-2743, H-4021 and H-4126) were studied in the experiment. The experiment was laid out in a split plot cum confounded design with two replicationsenThesis