We studied the effect of pretreatment with daily short-term temperature drops (DROP) on the content of photosynthetic pigments in the leaves of nematode-infected potato plants. No differences between healthy and infected plants were found as regards carotenoid content. Infection with nematode resulted in a rise in chlorophyll content in the leaves of the control plants, whereas DROP treatment caused it to decrease. Presumably, the differences in the content of chlorophylls may be related to the metabolic status of the plants at the time of infestation. DROP treatment appears to be a priming promoting the plants’ resistance to the nematode.