Integrated Seed Health (ISH) strategy

To address the problem of PSD in low-income countries, Thomas-Sharma et al. proposed an Integrated Seed Health (ISH) strategy. It involves 1) on-farm practices that can maintain or even improve seed quality; 2) the adoption of varieties that degenerate slowly due to their natural resistance to the organisms that cause PSD; and 3) a more strategic use of certified seed (i.e., buying in small amounts or less frequently, depending on the other components of ISH). This approach was developed as part of the RTB, which initiated a project in 2012 to solve the problem of degeneration in RTB crops.

The target beneficiaries of this project are small-scale potato farmers in Georgia, who will improve the quality of planting material, boost their productivity and yield stability, and consequently increase theirs and their families’ income and quality of life. Increased profitability of the potato crop could also benefit consumers through lower and/or more stable prices. An improved seed system will lead to more efficient diffusion of new varieties, which has benefits to farmers and consumers that transcend productivity. For example, CIP is currently developing potato varieties enriched with micronutrients such as iron and zinc. These varieties will be introduced in Georgia via the CIP–MoA potato initiative as a way to address malnutrition problems due to nutrient deficiencies. Iron deficiency is of particular concern in Georgia for women of reproductive age and children aged 3–15 years . The proposed research will lead to a greater awareness among farmers of the problem of PSD and its causes.

Although it is difficult to quantitatively predict the benefits to the target group, previous CIP experience would indicate that very significant increases in productivity can be expected by improving seed quality. For example, researchers in Sub-Saharan Africa (SSA) have shown yield increases of ~30% on average with one season of the PS approach. PS is not 100% efficient—farmers might miss latently or even mildly infected plants—so some yield loss would still occur. Presumably, these studies present a highly conservative estimate of actual yield losses in farmers’ fields caused by degeneration. As well, raising awareness of how to properly manage potato fields would facilitate the adoption of good agronomic practices, further increasing current potato yields in Georgia.

There is also strong evidence that host resistance to PSD pathogens benefits farmers. Several seed degeneration studies have compared two or more varieties, sometimes with known levels of resistance, and indicated differences in yield loss. In Kenya for example, after four seasons the overall yield reduction in genotypes resistant to multiple viruses ranged from 5% to 33%, whereas yield reduction in the local Ugandan and Kenyan varieties ranged from 56% to 58%.

Analysis of development problems. Georgia has excellent agronomic and environmental conditions in highland areas where high-quality seed can easily be produced. During the Soviet era, however, both seed production and seed certification management were centralized in the Soviet Union and basic seed was produced in Russia, Belarus, and Ukraine. This seed was then shipped to other Soviet countries, including Georgia, for further multiplication and eventual certification. Thus, a full seed production chain did not exist in Georgia at that time. With the collapse of the Soviet Union, the flow of basic seed and support for certification stopped, effectively ending certified seed production in Georgia. Subsequently, some high-quality seed has been imported from Europe, but in small amounts; even after multiplication in Georgia it represented less than 10% of seed needs. There is currently no control on the quality of imported seed.

Agriculture in Georgia is characterized by smallholders: there are about 656,000 farm holdings with an average size of about 1.25 ha distributed in scattered parcels of land. On the basis of the national statistics and knowledge of farm size, an estimated 50,000 households are engaged in potato production as a commercial activity and/or for domestic consumption.