Probing behavior of Dysmicoccus brevipes mealybug in pineapple plants1

Abstract

Differences in susceptibility to viruses in plants may be partially explained by the insect vector probing behavior and by the presence of phenolic compounds, which are often associated with defense strategies. This study aimed at detecting barriers that may difficult the probing activity of the Dysmicoccus brevipes (Pseudococcidae) pineapple mealybug, a vector of the pineapple mealybug wilt-associated virus, as well as evaluating the phenolic content of plants, in order to verify any possible relationship with the probing behavior, by using the electrical penetration graphs (EPG) technique. Seedlings of 'Smooth Cayenne' and 'Pérola' pineapple cultivars were used in the experiments. Only 28 % and 21 % of the mealybugs reached the phloem of the 'Smooth Cayenne' and 'Pérola' cultivars, respectively, over 16 h of recording, with an average of 9 h to reach the phloem vessels. The xylem phase was extended in both cultivars and represented approximately 31 % ('Smooth Cayenne') and 44 % ('Pérola') of the recording time. The phenolic contents of both cultivars were similar.

Interaction between mealybugs (Pseudococcidae) and coffee plants

“…This performance is related to the reproductive success depending on their ability to avoid and/or overcome the plant defenses present at the cuticle, epidermis, mesophyll and phloem levels. As an example, plant surface presents hair, thorns, trichomes and thick cuticles, which may exert some action preventing mealybug settling (Renard, 1993;Le Rü et al, 1995;Souza, 2016).…”

“…Ingested food directly influences the distribution and abundance of insects, affecting biological parameters such as fecundity, longevity, development and behavior (Silveira-Neto et al, 1976). As phloem sap sucking insect, mealybugs (Pseudococcidae) are greatly influenced by the quality of the phloem sap Souza, 2016).…”