Mulberry geometrid

Taxonomy: The mulberry geometrid Phthonandria atrilineata (Butler, 1885) is a moth species belonging to the order Lepidoptera and the family Geometridae. It is recognized as a specific pest that poses significant risks to mulberry (Morus) cultivation in various parts of Asia and beyond.

Host plants: The primary host plant for this insect is the mulberry tree. The larvae are oligophagous, feeding primarily on the leaves of mulberry species. This makes the pest particularly damaging to sericulture, where the quality and quantity of mulberry leaves are vital for silkworm rearing.

Biology and life cycle: The species completes a full metamorphosis consisting of egg, larval, pupal, and adult stages. Depending on climatic conditions, it can undergo multiple generations per year. The insect typically overwinters in the pupal stage, buried in the soil or protected within crevices of the host plant bark.

Damage and economic impact: Larvae are voracious leaf eaters. Early instars skeletonize the leaves, while later instars consume the entire leaf lamina, leaving only the main veins. Widespread infestation leads to severe defoliation, which hampers the tree's photosynthetic capability and reduces overall plant vigor and fruit yield.

Control measures: Management of Phthonandria atrilineata requires integrated pest management (IPM) strategies. This includes mechanical practices like soil cultivation to disrupt pupal stages, the installation of physical barriers to trap migrating larvae, and the targeted application of insecticides or biopesticides when scouting thresholds are exceeded.