Some Factors Affecting Localized and Systemic Necrotic Reactions to Virus Y in the Potato

Abstract

Factors influencing hypersensitive and necrotic reactions to virus Y in potato seedlings, developed from common varieties like Katahdin and Snowflake, have been studied mainly by means of hand inoculation in the greenhouse. This method provides more accurate and etailed information than either graft inoculation or aphid inoculation. The virus dosages applied by aphid inoculation have not been sufficient to assess the hypersensitivity of seedlings accurately.