Impact of yeast extract, zinc sulphate and organic fertilizers spraying on potato growth and yield

This study was carried out at a private farm in proximity to the Faculty of Agriculture, University of AL-Qasam Green, Babylon, Iraq with an objective to evaluate the performance of manure, organic poultry residuals, dry yeast extract and zinc sulfate on growth and yield of potato. The experiment was arranged in a split-plot within a randomized complete block design keeping three poultry litter doses (0, 1.5 and 3 Mt/ha) as the main plot treatments and five dry yeast extract doses (0, 2, 4, 6 and 8 g/l) and two zinc sulfate (ZnSO₄) doses (200 and 400 mg/l) as the sub-plot treatments. The interaction of 3 Mt/ha poultry litter in combination with 8 g/l dry yeast produced the plants with the longest vines. The interaction of 1.5 Mt/ha poultry litter in combination with 4 g/l dry yeast extract produced the maximum stems, highest chlorophyll level, highest leaf area and most total and marketable tubers. Likewise, the interaction of 3 Mt/ha poultry litter in combination with 200 g/l ZnSO₄ produced the heaviest tubers and maximum total and marketable yields. The interaction of 1.5 Mt/ha poultry litter in combination with 8 g/l dry yeast produced maximum percentage of dry matter and starch. The best response for higher total and marketable yields was recorded with the application of 3 Mt/ha poultry litter in combination with 200 g/l ZnSO₄.