Effects of Different Growing Media on Yield and Growth Parameters of Potato Minitubers (solanum Tuberosum L.)

Seed potatoes (Solanum tuberosum L.) are increasingly produced by minitubers originated from tissue culture techniques to eliminate the chance of infections by viruses. The aim of this study was to evaluate the suitability of several potting media for minituber production in the greenhouse environment. Six growing media treatments were used in a randomized complete block design with four replications. Treatments included perlite, soil, perlite + vermiculite (1:1 v/v), perlite + peat moss (1:1, v/v), perlite + soil (1:1, v/v), perlite + soil + composted cattle manure (4:3:3 v/v), and perlite + soil + vermicompost (4:3:3v/v). All treatments except treatments that contained composted cattle manure or vermicompost were subjected to daily application of nutrient solution. Growing media were analyzed for a selected number of physical and chemical properties. Tuber yield and yield parameters were determined 75 days after planting. Leaf area, shoots, and root DW and FW and concentrations of N in roots and shoots were measured at tuber bulking stage. The highest value of particle density and bulk density and the lowest value of porosity and EC were obtained for the media that contained Perlite. The greatest value of leaf chlorophyll index throughout the growing period was observed at perlite + soil + composted cattle manure and perlite + soil + vermicompost, likely due to excess availability of N. The maximum contents of N in the shoot root and tubers were observed in perlite + soil + composted cattle manure. Fresh and dry minituber yield and number of minituber per m(2) shoot and root FM and DM yield were greater in growing media without soil than the containing Compound with soil. The fertigated perlite + peat moss (1:1, v/v) resulted in the greatest yield among treatments likely due to desirable EC, pH, and porosity. This treatment can be recommended as a suitable media for the production of potato minitubers in greenhouse environment.