Gelling Agents and Partial Agar Replacement In Vitro for Production of Potato Plants

Abstract

The potato crop (Solanum tuberosum L.) is susceptible to pathogens that reduce its production. The micropropagation technique is used to reduce contaminants in seedlings, which requires gelling agents, with agar being the most used, which increases the cost of production. This study consists of two experiments: one with the cultivar Atlantic, under a completely randomized design, containing five treatments, with four replications, where three concentrations of Agar (6,5 and 4 gL-1) were tested, one concentration of Phytagel (2.5 gL-1) and the partial replacement of Agar adding Galactomannan (5+5 gL-1 ) and another with the Atlantic and Markies cultivars, under a completely causal experimental design, in a 2x5 factorial analysis, with the two cultivars and the same five types of gelling agents, containing 10 treatments, with four repetitions; 30 days after multiplication, morphometric evaluations were performed. After 30 days of acclimation, ex vitro survival, length of root, shoots and number of leaves were evaluated. For the statistics analysis, were used the R program and the variables compared using the Tukey test at 5 % of probability. It was concluded the partial replacement of Agar by Galactoman is possible, lowering the concentration of Agar to 5gL-1, where great results are obtained in the growth of explants, reducing the production cost in micropropagation and acclimatization of the cultivars Atlantic and Markies. There were no differences between agar at lower concentrations and the use of phytagel in the production of seedlings of cv.s Atlantic and Markies.