Pentas lanceolatus as a nectar source for Larra bicolor and its effect on parasitism of Scapteriscus mole crickets

Larra bicolor was one of three classical biocontrol agents released into Florida in response to losses in pasture and managed turfgrass from Scapteriscus mole crickets. Larra bicolor distribution in North America now includes Florida, Mississippi, Alabama, and Georgia. Nectar sources influence the successful establishment of L. bicolor. In 2007 and 2008, a replicated garden containing 14 ornamental plant taxa was established. Numbers of wasps feeding on these plants was recorded. Wasps foraging on flowers are reportedly male biased. Therefore, the same garden was used to determine daily foraging time and sex ratios of L. bicolor feeding on flowers in a separate experiment. In the garden experiment, only pentas and Spermacoce veticillata were successful in recruiting wasps, and were used in the laboratory to determine wasp longevity. Spermacoce verticillata is a naturalized flowering weed used to monitor wasp activity in Florida. White-flowered pentas had comparable numbers of wasps in both years and was comparable in wasp longevity in laboratory experiments. Male wasps are present throughout the foraging period whereas females are transient presumably going back and forth between nectar sources and foraging for mole crickets. A field study was established to determine the link between nectar sources and parasitism. For lack of wasps on flowering pentas in summer 2008 likely due to hurricanes and above average rainfall, this experiment will be repeated in 2009. In conclusion, pentas appears to be a viable substitute as a nectar source for Spermacoce and may be incorporated into landscapes to enhance biological control of mole crickets.