Effect of Various Levels of Nitrogen Fertilizer and the Nutrient Solution Acidity on the Physiological Characteristics and Mini Tuber Production of Potato (Solanum tuberosum L.)

In order to optimize the conditions and also increase the production of potato mini tuber in Agria cultivar, the effects of various amounts of nitrogen and acidity of nutrient solution in two separate experiments in 2013 in a completely randomized design with three replications in a hydroponic environment in a research greenhouse of the Faculty of Agriculture of Ferdowsi University of Mashhad was carried out. In one experiment, different levels of nitrogen (zero milligrams Hoagland solution (control), 50 milligrams Hoagland solution and 100 milligrams Hoagland solution) was in the form of ammonium nitrate and in another experiment, Hoagland protein solution acidity was at three levels (3, 4 and 5/6). Three times after seedlings transplants to planting bed (30. 35 and 40 days after planting), the acidity treatments were applied for 10 hours on the plants and after that leaching was arranged. The results indicated that increasing the amount of nitrogen caused an increase and reduction of acidity caused reduction of photosynthesis, transpiration and chlorophyll a and b concentrations compared with the control. The increase in nitrogen from zero to 100 milligram per liter and the temporary reduction of acidity from 5.6 to three increased the mean weight, diameter and number of micro tubers. an increase in mean weight, diameter and number of mini tubers. Increasing nitrogen content increased and reducing the acidity of the nutrient solution reduced leaf area and dry weight of the shoot. The number of micro tubers did not differ significantly with increasing nitrogen levels from 50 to 100 milligram , which indicates that increasing nitrogen consumption increases the number of tubers to a certain extent, but since then, does not significantly change the yield and may even have negative effects In general, it seems that consumption management and the application of appropriate amount of nitrogen fertilizer and short-term reduction of dietary acidity of acid solution can frequently play an important role in increasing the production of micro tubers and yield in this plant.