Effects of seed tuber storage condition and dormancy breaking treatments on growth and yield of ware potatoes (solanum tuberosum i)

Abstract

Two experiment s were conducted between November 1994 and February 1995 at Field Station, University of Nairobi, Kabete campus, to investigate how different storage conditions and dormancy breaking treatment affect sprouting of potato (Solanum tuberosum L.) seed tubers and the subsequent performance of the plants from those tubers in the field. The first experiment involved arranging potato seed tubers of Nyayo and Roslin Eburu (B53) cultivars in chitting trays in three (one, two and three per tray) layers and then storing the tubers under either diffused light or dark conditions for a period of twelve weeks before planting in the field. A randomized complete block design experiment with three replicates was used. The second experiment involved treating freshly harvested seed tubers with four (0, 0.5, 1.0, 1.5 cc/kg) concentrations of Rindite to break dormancy and then planting them in the field after two weeks. Same experimental design as an the first experiment was used. Seed tubers stored in the dark had sprouts which were significantly longer in l~ngth and had higher fresh and dry weights than those stored in diffused light. Plants from seed tubers stored in dark emerged significantly earlier than those stored in diffused light. However, plants from diffused light scored seed tubers were more vigorous and tended to grow faster than those from dark stored seed tubers. At maturity, plants from diffused light stored seed tubers outyielded those. from dark store seed tubers by 2.6 t/ha and 6.6 t/ha in the first and second season respectively. However the difference was only significant in the second season. Number of layers of seed tubers in chitting trays did not significantly affect the yield of plants. Rindite application significantly influenced sprouting of potato seed tubers and the performance of the subsequent plants in the field. The higher the Rindi te concentration used the greater the sprouting of seed. tubers and the higher the vigour and eventual yield. The optimum concentration was found to be 1~0 cc/kg tuber since the difference between 1.0 cc/kg tuber and 1.5 cc /kg tuber for total tuber yield was not significant