Investigations on some of the important host plants of Kerria lacca with reference to phloem distance

Background: Kerria lacca, the Indian lac insect, is a phytophagous (sap-feeding) insect thriving on mostly woody dicotyledonous plants. Of more than 400 plant species known to be likely hosts for the lac insect, about 113 host species are found to be successfully infested by the lac insect in India. Architecture of the plant tissue might be a crucial factor for these sap feeders, because for successful establishment, the insect has to pierce the plant tissue to reach the feeding site, viz., the phloem or the xylem tissue. Materials and Methods: Twenty-two diverse host plant taxa classified on the basis of lac yield and insect preference were considered. Anatomical and statistical studies were conducted using distance to the phloem from the stem periphery as a parameter. Results: Statistical observations showed that host preference and lac yield is independent of phloem distance. Conclusions: Other factors such as the contents of carbon, nitrogen, or certain secondary metabolites present in the host plant may be involved in lac insect-plant interaction, which warrant further investigation.