Nutrient-encapsulation of potato nodal segments for germplasm exchange and distribution

Nutrient-encapsulation technique using in vitro grown nodal segments was developed as an alternative method for distribution of potato germplasm. The nodal cuttings of two potato genotypes, Kufri Jyoti and Kufri Lauvkar, were encapsulated in calcium-free Murashige and Skoog's (MS) medium containing either 2 or 3 % sodium alginate and 0, 1, 2 or 3 % saccharose. The encapsulated segments were stored in tubes with or without semisolid MS medium, and incubated in the dark at 25 ± °C for 3 to 6 weeks. Presence of saccharose in the beads was found detrimental for regrowth of new shoots. In absence of saccharose, about 82 % and 53 % encapsulated segments initiated regrowth after 3 and 6 weeks of dark storage, respectively, in tubes containing MS medium. Storage in empty tubes deteriorated the encapsulated segments, and depressed shoot formation. For potato germplasm distribution, the encapsulated segments can be transported in small tubes containing semisolid MS medium. This revised version was published online in July 2006 with corrections to the Cover Date.