Effect of NPK Media Concentrations on In Vitro Potato Tuberization of Cultivars Nicola and Russet Burbank

Our objective was to test whether the NPK levels in commonly used Murashige and Skoog (MS) media are optimal for microtuberiztion for the two cultivars tested. Two N (N1 = 841 and N2 = 1418 mg L−1); three P (P1 = 39, P2 = 76.9 and P3 = 115 mg L−1; and two K (K1 = 784 and K2 = 1518 mg L−1) media concentrations were evaluated for microtuberization. Higher levels of N2P3K2 were more effective for microtuberization than the lower levels of N1P1K1 in standard MS media. N2P3K2 was the best concentration for all yield components studied, tuber number, tuber weight, and stem and root weight. For the two cultivars, our results suggest that higher NPK levels than those in MS media would enhance in vitro microtuberization, and that optimum NPK levels could vary for cultivars.