Physiological eveluation of potato (Solanum Tubersum L.) cultures : thesis submitted to the G.B. Pant University of Agriculture and Technology Pantnagar (Nanital) U.P. in partial fulfilment of the requirements for the degree of Doctor of Philosphy (Horticulture) April, 1984 - Singh, Ram Pratap (G.B.Pant University of Agriculture and Technology Pantnagar, 1984)