One of the major constraints to cost-effective potato production among marginal resource-poor farmers in developing countries is the lack of quality potato seed available to them at affordable prices. Potato seed programs have been effective in producing only small quantities of quality seed, supplying less than five percent of the seed needed in developing countries.

Providing farmers with access to true potato seed (TPS) technology (planting with botanical seed instead of tubers), affords them the opportunity to produce quality seed at a low price. The fact that TPS can be used advantageously for the production of seed tubers in high density nurseries is an especially important factor in developing countries where land is scarce or marginal farmers grow potatoes in small plots. Because TPS is free from the major potato diseases, quality seed tubers can also be produced. Equally important to resource-poor farmers is the capability of TPS to be used quickly to mitigate potential agricultural disasters.

GOALS. The goal of the CIP breeding program is to develop improved TPS varieties and parental lines that are suitable for the changing needs in developing countries. CIP’s TPS breeding approach is based on using genetic male sterility in order to develop female lines suitable for the commercial production of TPS; conventional and novel methods such as parthenogenesis to improve parental lines; and incorporating resistance to late blight in TPS varieties.

High priority is also placed on widening the genetic base of the TPS materials and exploring the use of tuber yield heterosis from crosses between Solanum tuberosum and S. andigena. CIP breeders will continue to strengthen their partnerships with key breeding research institutions to maximize all opportunities to test new TPS varieties.

OUTPUT. In order to achieve improved TPS parental lines and TPS progenies for the Indo-Gangetic plains, subtropical highlands of East Asia, and Andean highlands, a breeding and evaluation scheme will be strengthened so as to better facilitate progeny testing for the identification of best TPS parental lines and TPS progenies. Plans are underway to improve the TPS parental lines and locally select adapted TPS progenies based on tuber characteristics that reflect a genetic background exhibiting early tuber yield and late blight resistance.

Twenty grams of TPS is sufficient to produce enough seedling to plant one hectare of potatoes. That is a far cry from the metric tons of conventional seed tubers required for the same area.

STRATEGIES FOR TPS PRODUCTION AND BREEDING. A survey of TPS users by CIP researchers will be aimed at identifying TPS strengths and user preferences. This information will be extremely useful in identifying researchable issues and priorities and will also be used to assist in developing strategies for TPS breeding and production. The first survey will be undertaken in Peru, where TPS has been distributed to marginal farmers for more than four years. This initial effort may be used as a model in other selected countries according to needs.

IMPACT. CIP estimates that more than 110,000 rural households are beneficiaries of TPS bred through CIP’s pioneering breeding program. Their studies also indicate that marginal farmers in India, Vietnam, Bangladesh, Peru, Nepal, and Indonesia are using TPS as the source of their planting material for seed tuber production.

In northeast India and Bangladesh, for instance, TPS has shown to be high tuber-yielding and is better or comparable to the traditionally sown potato variety, Kufri Jyoti. In Vietnam TPS is an alternative to quality tuber seed which is lacking. In the remote Andean communities of the Callejón de Conchucos of Peru, TPS has been utilized to increase food supply and eradicate famine that was of common occurrence before the introduction of TPS.

In some parts of Peru, Chacasina, a TPS hybrid developed at CIP, has allowed farmers to produce at levels three times the country’s national potato production average.

In spite of these remarkable strides, poor farmers still have access to a very limited number of the TPS varieties they need to help them compete in their markets. Clearly, TPS varieties with late blight resistance, high tuber yield, and good tuber characteristics continue to be in great demand.

This project will help to increase productivity and attain food security resulting from the utilization of improved TPS varieties that incorporate early tuber yield and resistance to late blight. The increased number of different TPS varieties developed here will contribute to widening genetic diversity, and also contribute toward a sustainable seed production where TPS is used to re-establish the traditional seed system by means of reducing genetic vulnerability. Main beneficiaries will be small-scale farmers. Income generation will increase among poor farmer-users of TPS as a result of its low cost and high quality seed.

For more information, please contact Enrique Chujoy, Germplasm Enhancement and Crop Improvement Division, Apartado 1558, Lima 12, Peru, or at e.chujoy@cgiar.org