Effect of potassium fertilization on potato crop (S.tuberosum) growth and yield [Sudan]

Field experiments were carried out for two sucessive seasons, (93/1994 and 94/1995) to investigate the effect of potassium fertilization on the growth and yield of potato crop (Solanum tuberosum L.), grown in the demonstration fram, Faculty of Agriculture, Shambat. Potassium fertilizers used included potassium chloride and potassium sulfate at different levels (0.40,80 and 120Kg K2O/fed) a rranged in acomplete randomized block design. Plant samples were collected during the growing season for growth and chemical analysis. Plant parameters measured included the number, fresh and dry weights of stem, leaf and tubers. For root fresh and dry weights were recorded. The yield records includ fresh and dry weights of harvested tubers and tuber size distribution. Chemical concentration of nitrogen, phosphrus potassium, calcium, magnesium and sodium in leaves were measured. Soil samples were collected after harrvest ad soil analysis was carried out to investigate the effect of potassium on some soil properties. Soil properties studied included the soluble cations, soil pH, available soil phosphrus, total nitrogen and the electrical conductivity of saturation extract. The attained results indicated that the potassium application did not affect vegetative growth early in the season but as the season proceeded, the growth was increased, more tubers were produced with an increase in size as well. Plant analysis indicated an increase in leaf phosphrus, potassium and adecline in leaf calcium, magesium and sodium as result of potassium addition. Soil analysis showed slightly decreased in soil pH (paste) in the top soil, but soil potassium remained unchaged. Potassium fertilizer increased soil nitrogen contet partiularly addition of potasium sulfate. Soil available phophrus was slightly increased by the added potassium. Soil magnesium was signifcantly affected, but soluble calcium and sodium were not affected