THE EFFECT OF SEEDPIECE POPULATION AND HARVEST DATE ON YIELD AND ECONOMIC VALUE OF CARLTON POTATOES IN MANITOBA

Abstract

The effect of seedpiece population on Carlton potatoes for the early tablestock market was evaluated under rainfed conditions in southern Manitoba over the 1982, 1983 and 1985 growing seasons. Populations of 21.7, 26.3, 33.3, and 45.5 thousand seedpieces per hectare were harvested 75, 85 and 95 d after planting each year. Total and marketable tuber yields increased with population. Tuber specific gravity increased with population in 1982 and in the first two harvests in 1983, but no trends were observed in 1985 and in the final harvest in 1983. The incidence of hollow heart in marketable tubers was very low in all 3 yr, and was not related to seedpiece population or date of harvest. Net crop value (NCV) usually increased with successive harvests within each year, and generally showed a positive relationship with seedpiece population.Key words: Potato, Solanum tuberosum L., Carlton, seedpiece population, hollow heart, specific gravity