1Division of Crop and Soil Science, Central Potato Research Institute, Simla-171001, (H.P.).
Field experiment was conducted on the sandy loam soil at the Central Potato Research Institute, Simla during 1978 and 1979 to study the effect of N fertilization on the concentration and yield of ctude and true proteins in potato tubers of Kufri Chandramukhi and Kufri Jyoti. Kufri Jyoti tended to give higher protein content than Kufri Chandramukhi. The interaction between the varieties and N-fertilization on protein was not significant. N application, however, exerted a highly significant on influnce on the crude and true proteins of tubers when applied upto 150 kg N/ha and thereafter N fertilization depressed the concentration of crude and true protein. N fertilization almost doubled the crude and true protein yield of potato tubers. True protein was highly associated with crude protein and constituted 44% of crude Protein. N and P in leaf blades collected after 75 days of planting showed positive association with crude or true protein of tubers. P in tuber also showed positive association with the proteins. K in the leaf blade or tubers showed negative association with the crude or true protein. Nitrogen fertilization in general tended to increase P but decreased K content both in the leaf blade and tubers.
