Megacopta cribraria, also called the bean plataspid, kudzu bug, globular stink bug and lablab bug, is a shield bug native to India and China, where it is an agricultural pest of lablab beans and other legumes. The bug, while harmless to houseplants and people, often enters houses. It is attracted to white surfaces such as the walls of houses or white vehicles, because of the high reflectance of the white surfaces as it relates to the bugs' simple eyes. As a defense mechanism, they emit a foul-smelling pheromone that also acts as a congregation pheromone. Aside from smelling foul, the liquid also creates a burning sensation and sometimes leaves a red welt on bare skin. It is similar to other Plataspidae in having a somewhat unusual symbiotic relationship with its gut bacteria. Before laying eggs, females deposit particles containing the symbiont, which are then eaten by newly hatched nymphs under natural conditions. Nymphs experimentally deprived of access to the symbiont exhibited slower growth, smaller body sizes and higher mortality.The bean plataspid gives off an offensive odor when touched, squashed, or poked. Hosted by wisteria, green beans, and other legumes, the insect sucks juice from the stems of soybean plants and reduces crop yield. However, when the insect infests kudzu, another invasive species, it appreciably reduces the growth of that plant.

In the Southeastern United States, M. cribraria is an invasive species, and was first noticed in northeastern Georgia in 2009. As of 2012, it was spreading rapidly into the surrounding states of Alabama, Florida, North Carolina, South Carolina, Tennessee, and Virginia. It has recently begun to invade Maryland and Mississippi, as well. In 2017, M. cribraria was observed in Texas.

Southeastern United States

Universities and corporations throughout the Southeastern United States have begun research into alternative means of dealing with the kudzu bug. Universities in Georgia, South Carolina, and North Carolina, such as North Carolina State University and Georgia State University, have produced publications since 2011 until 2014 regarding M. cribraria pest management. One recent work demonstrates that the kudzu bug's diet in Alabama is broader than originally believed.

Current research

M. cribraria lives in symbiosis with the bacterium Candidatus Ishikawaella/Candidatus Ishikawaella capsulata. This symbiont is retained in the eastern North American invasive range, so its successful invasion and devastation of crops there is not due to symbiont switching. This is unsurprising given that M. cribraria has not switched host plants, and symbiont switching is a strategy which has been seen in invasive insects which need to digest an unfamiliar host native to their new range.

Symbionts

harmful

bite

Megacopta cribraria, commonly known as the kudzu bug, is considered a tree pest because it feeds on the sap of various tree species, including soybeans, wisteria, and kudzu, causing damage to the foliage and potentially impacting the health and growth of the trees.

tree pest

Megacopta cribraria, also known as the kudzu bug, is considered a garden pest because it feeds on various garden plants, including vegetables and ornamental plants, causing damage to the foliage and potentially reducing the yield and aesthetic value of the garden.

garden pest

Megacopta cribraria, commonly known as the kudzu bug, is considered a crop pest because it feeds on crops such as soybeans, causing damage to the plants and potentially reducing crop yields, leading to economic losses for farmers.

crop pest

Megacopta cribraria, commonly known as the kudzu bug, is considered a pest because it feeds on various tree species, garden plants, and crops, causing damage to the foliage and potentially reducing yields, leading to economic losses for farmers and impacting the health and growth of plants.

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What are some traditional uses of bean Plataspid insects in other cultures?

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