• USDA

The develop of kudzu bugs (Megacopta cribraria) is likely impacted by two important biotic factors. The first is what host plant they develop on, and the second is the presence of a known beneficial, symbiotic bacteria. In the case of Megacopta, the two primary host plants in the United States appear to be kudzu and soybeans. The ability for the Megacopta to utilize different host plants is thought to depend on the presence and genotype of the bacterial symbiont stored in the gut of the insect (Fukatsu & Hosokawa, 2002; Hosokawa et al., 2007). The obligate symbiont present in the Megacopta gut is known to be a bacterium called Ishikawaella capsulata (Fukatsu & Hosokawa, 2002). The transfer of bacteria from one generation to the next is accomplished through the use of a protein capsule manufactured by the mother, loaded with symbiont, and deposited with the egg mass.This novel mode of transmission allows for convenient study of the development and fitness of M. cribraria with and without the symbiont. We are testing how host plants and symbionts interact to impact the development and survival of the kudzu bug. Much of this work is being carried out in field experiments sponsored by the Doraville Unity Garden in Doraville, Georgia.

During the spring and summer of 2012, we will rear M. cribraria from egg to adult emergence, and measure the timing and rate of development, body size at each life stage, and mortality.The experimental design contains four treatments consisting of two host plants, and the presence and absence of the symbiont There is a secondary question that is of agricultural importance, namely the impact of M. cribraria on the growth of soybeans. A subset of the soy will be grown without M. cribraria in order to measure the biomass of these plants over a season with and without this insect. This will provide an empirical estimate of the agricultural impact of this pest on the growth of soybean.