ABSTRACT
Poor seed quality is often cited as the most important factor limiting potato productivity in developing countries (Rasco 1994). Improving tu ber seed quality and availability is institutionally complex in the tropics and subtropics. Progress of public sector (government-financed) seed pro grams has usually been slow and disappointing even in countries where sites for seed multiplication are agroecologically attractive (Crissman 1987). True potato seed (TPS) is a captivating technological alternative that of fers farmers an option to overcome the aforesaid weaknesses of clonally propagated tubers as a source of planting materials. Side-by-side com parisons of a jar of TPS with twenty 100 kg bags of clonal planting material-the amounts needed to plant one hectare (ha)—are visually impressive evidence of the potential of the technology.*
Although the investment in agricultural research and extension of TPS technologies is small compared with the amount spent on clonal seed technologies and selection systems, sufficient experience has accumulated, largely over the past 20 years, to review achievements, shortcomings, and future prospects (Almekinders et al. 1996; Simmonds 1997). "At
Corresponding author: T.S. Walker, e-mail: walkerts@msu.edu; present US mailing address: Michigan State University, Department of Agriculture Economics, 207 Agriculture Hall East Lansang, MI 48824-1039, USA *A jar of TPS as planting material is equivalent to 2,000 kgs of clonal planting material; i.e., a common seedling rate/ha for potatoes.
