Influence of drought on the insect-plant interaction between Macrosiphum euphorbiae And Chilean Solanum tuberosum cultivars

Abstract

The centre of Chile is the largest agricultural production area of the country. It is particularly exposed to drought episodes, which are and will be more frequent in the future. To date, few information are available regarding drought effect on the interaction between insect pests and potatoes, which is one of the most important crops grown in Chile. In this study, a trade-off hypothesis between potatoes drought tolerance and resistance to aphids was tested. Two cultivars of Solanum tuberosum differing by their drought tolerance were subjected to reduced water availability. Preference tests, probing behaviour and reproductive performance experiments were conducted with the potato aphid Macrosiphum euphorbiae. The impact of M. euphorbiae on potato development was also assessed. Results show that the two studied cultivars respond differently to drought, and that aphids show di erences in host preference, feeding behaviour and preproduction performance, where the drought level applied does not seem to greatly in uence aphids. However the trade-off hypothesis is not the best- tting hypothesis to explain the variations in this insect-plant interaction. The present study provides informations about how plant-insect interactions can be modified in drought conditions, as few information is available to date on this specific stress combination.