Culture media in the in vitro multiplication of ‘Inhame da Costa’ (Dioscorea rotundada Poir.)

Yam plays an important socioeconomic role in Northeastern Brazil, but the use of low-quality seed tubers is an obstacle to cultivation. The micropropagation technique can work around this problem, as it allows the production of high quality phytosanitary seedlings. The objective of this work was to evaluate different culture media in the in vitro multiplication of ‘Inhame da Costa’ plants. Mini-cuttings with one lateral bud were inoculated in flasks containing MS, Galzy and 2GGC culture media, in solid and liquid consistencies, in an experimental design entirely randomized in a 3 × 2 factorial scheme. Cultivation was carried out in a growth room with 27 ± 1 °C, photon flow density of 30 μmol m-2 s-1 and photoperiod of 16 hours. At 90 days of cultivation, the plant height (cm), the number of shoots, the number of senescent leaves, the number of green leaves, the number of minicuttings and the fresh and dry masses of aerial parts and roots (mg). The explants were 100% responsive in all treatments and the 2GGC medium was the most efficient for in vitro multiplication, with liquid consistency being the most suitable for the micropropagation of ‘Inhame da Costa’.