Pathogen free Potato Plant Regenerated from Meristem Tip-Cultures

Abstract

In Pakistan the potato cultivars grown from local seed are usually affected by virus disease which is seed borne. Healthy and disease free seed is imported at the expense of heavy foreign exchange. Meristem-tip culture techniques has been used effectively for the eradication of potato viruses. The project was therefore, undertaken to develop technique for regeneration of pathogens-free plants from meristem tips of potato cultivars in vitro, to achieve this objective including others, tissue culture laboratory with basic facilities has been established in the department of Plant breeding and Genetics, Sindh Agricultural University, Tandojam. Meristem tips of four potato cultivars were collected aseptically in agar medium of MS inorganic salts with thiamine HCL, supplemented with NAA and CA3 The medium supplemented with NAA produced 60 to 80 percent plantlets with both root and shoot formation, while CA3 supressed bud proliferation and induced root generation. Vegetative multiplication was continued by successive sub-culturing of each node of regenerated plant on the same medium but with 2% sugar. However, striking difference in growth response was observed in different cultures. In one culture the seed formation (Micro Tubers) was observed. The bud proliferation was also observed in same cultures, which have been sub-cultured. More then 300 cultures are maintained presently in the tissue culture laboratory. Callogenesis is also initiated and maintained from the potato ex-plant. The acquaintance with different tissue culture techniques used with different crops including potato have been achieved in the approved project objectives.