Taxonomy of Bruchus pisorum:
– Bruchus pisorum was described by Linnaeus in 1758.
– Linnaeus created the genus Bruchus for seed-beetles, with B. pisorum as the type species.
– Originally placed within Curculionidae, the genus Bruchus was later separated into its own family, Bruchidae, by Spinola in 1843.
Description of Bruchus pisorum:
– Bruchus pisorum is a short stout beetle with an oval body.
– It can range in color from soft grey to black with white patches.
– The elytra are shorter than the abdomen, exposing large white patches.
– The head is short and strongly constricted behind the eyes, with antennae extending to less than one-third of the body length.
Distribution and Habitat of Bruchus pisorum:
– Bruchus pisorum has a natural range in Asia minor but is considered cosmopolitan due to transport.
– It is a pest in pea-growing areas in the US, South America, South Africa, Japan, China, and is the principal pest of peas in Chile.
– The weevil prefers temperate climates, and infestation levels can vary based on environmental conditions.
Life Cycle and Behavior of Bruchus pisorum:
– Bruchus pisorum is a univoltine species with adult weevils leaving overwintering sites in Spring.
– Eggs are laid singly on pea pods, with larval development lasting seven to 11 weeks and pupation two to three weeks.
– The behavior of pea weevils is poorly understood, but they congregate along crop edges and females fly through crops searching for pea pods.
Impact on Pea Crops and Management Strategies:
– Bruchus pisorum infestation can cause economic losses by affecting seed quality and reducing market value.
– Farmers use various control methods such as crop rotation, certified disease-free seeds, proper storage practices, biological control agents, and integrated pest management approaches.
– Monitoring and early detection are crucial for effective management of Bruchus pisorum infestations.