The relationships between cacao viruses and their vectors: the feeding behaviowr of three mealybug (Hornoptera: Pseudococcidae) species

摘要: SUMMARY In transverse sections of cacao stems, 164 345 stylets Planococcoides (=Pseudo-coccus) njalensis were seen to end in the phloem. Passage through cortex was intra-cellular and entered phloem by avoiding peripheral blocks sclerenchyma. Stylets Ferrisiana virgata, which transmits viruses less readily than P. njalensis, also phloem, but often. Phenococcus madeiriensis, is not a vector viruses, fed differently; few stems none ended and, though its are long enough reach this tissue, they did extrude for full length when mealybugs on agar.