Effect of using certified and uncertified potato seeds on the yield and sanitary conditions of a potato crop

Abstract

The establishment of a potato crop must begin with a good potato-seed, ideally certified to assure its purity, sanitary condition, calibre and vigour. In Chile, small farmers do not have an easy access to this type of seed and do not understand the benefits of utilising these seeds.
With the objective of stimulating small farmers to use certified potato-seeds to obtain a product of high quality, demonstration plots were established in the locality of “Los Muermos”, situated in the Tenth Region of Chile, using the certified potato-seed of the Desiree cv. , widely produced in the region.
During a field day with farmers from the zone, the yield and the sanitary quality of the harvest from the demonstration plots was evaluated and compared.
Total yield of potato tubers (t/ha) was similar between the demonstration plot and the farmer plot. However, when the tubers were classified according to their calibre, form and sanitary conditiun (culling the tubers with more than 25% of the surface covered by black scab (Rhizoctonia solani), silver itch scabies,(Helminthosporium solani) common scabies(Streptomyces scabies) and dusty scabies (Spongospora subterranea)) the commercial yields were 48 t/ha and 26, 7 t/ ha, respectively. In terms of the sanitary condition of the tubers harvested, those produced with the certified seed were in better health than those coming from the uncertified potato variety.