Trupanea

Trupanea is a genus of tephritid fruit flies (family Tephritidae) recognized as significant pests of plants within the Asteraceae family. These insects are widely distributed across various continents and are particularly problematic in regions where sunflower, ornamental daisies, and other composite flowers are cultivated. Their impact is primarily observed in the destruction of reproductive plant tissues.

The host range of Trupanea is largely restricted to members of the sunflower family (Asteraceae). Larvae are gall-formers or tissue feeders that thrive within the flower heads of their hosts. This feeding behavior directly affects the plant's ability to produce viable seeds, causing significant economic losses in both commercial flower farming and seed production sectors.

The life cycle of these flies typically involves the adult females ovipositing into developing flower buds. Upon hatching, the larvae bore into the receptacle and feed on the developing ovaries and florets. The larval development stage is completed inside the flower head. Pupation often occurs within the dry remnants of the flower head or in the immediate soil surface, depending on the specific species and environmental conditions.

Signs of infestation include distorted flower shapes, wilting of petals, and the presence of larval exit holes or frass within the bloom. Because the larvae feed internally, external signs are often not immediately apparent until substantial damage has already been done to the internal structure of the flower, making early detection and proactive management crucial for mitigation.

Integrated Pest Management (IPM) strategies to control Trupanea include:

• Sanitation by removing and destroying infested flower heads to reduce the population load.
• Weed control aimed at eliminating wild Asteraceae that serve as alternative host reservoirs.
• Deep tilling of soil post-harvest to disturb pupae that have overwintered in the top layer.
• Application of appropriate insecticides during the budding stage to prevent oviposition by adult flies.