DIFFERENTIAL COMPETENCE FOR IN VITRO RAPID AND RELIABLE REGENERATION OF POTATO (SOLANUM TUBEROSUM L.) CULTIVARS

Abstract

The present study tested in-vitro growth and performance of 14 exotic and local potatoes (Solanum tuberosum L.) cultivars under artificial long-day conditions. The study carried out in four steps; 1) effect of medium (ten nutrient medium) on in vitro plant growth, 2) callus induction and shoot proliferation from internode and leaf disc explant, 3) selection of nodal explants (apical, 1^st and 2^nd nodes) and position, 4) acclimatization and ex-vitro plant growth of regenerated explants. The nutrient growth medium were statistically significant difference (P< 0.05) on shoot length, number of leaf/shoot and tuber formation. The M7 (MS salts + B5 vitamins) medium was most suitable and efficient for in vitro regeneration. Internode explants of 14 potatoes cultivars demonstrated significant differences (P < 0.05) among them and showed superiority for calli  induction compared to leaf disc explants. The redifferentiated from internode derived calli to adventitious shoot had positive responces on number of shoots (4.7) per plant of potato cv. Tokat-6/24 when subcultured on M7 medium containing 4 mg/l gibberellic acid_, 0.5 mg/l 6-benzylaminopurine, 0.2 mg/l naphthalene acetic acid. The maximum (91.7%) acclimatization and survival rate of in vitro regenerated plantlets noted on peat moss: perlite: sand (1:1:1) when compared to other three potting mixture. The in vitro regenerated potato plants were vigorous, and produced healthy tubers in pots as well as field conditions. However, this protocol can be use for development of genetic engineer and large-scale production of healthy & disease-free potato seed tubers.