Proboscidea louisianica: An Unreported Host of Heliothis virescens (Lepidoptera: Noctuidae)
The tobacco budworm, Heliothis virescens (F.), was found to be strongly attracted to devil's claw, Proboscidea louisianica (Mill.) Thellung, plants. Of 160 larvae collected from the plants in 1992, 99.4% were H. virescens, 0.6% were Helicoverpa zea (Boddie), 42.5% died from infection by undetermined disease pathogens, and 11.3% H. virescens were parasitized by Cardiochiles nigriceps Vierick. Of 112 larvae collected from P. louisianica in 1994, 90.2% were H. virescens, 9.8% were H. zea, 59.8% died from infection by undetermined pathogens, and 26.7% H. virescens were parasitized by C. nigriceps. Feeding studies showed that P. louisianica was a nutritionally poor host for H. virescens, backcrosses of H. subflexa X H. virescens, and H. zea; when compared with their development on semisynthetic diet, development was much slower, pupal weights were lower, and survival rates were lower for larvae fed P. louisianica than for those fed semisynthetic diet. None of the backcross or H. zea and only one H. virescens female developed on P. louisianica survived to reproduce. This study reports P. louisianica as a new host record for H. virescens. Data show that H. virescens can survive and reproduce on this plant and that P. louisianica could be a major host of H. virescens in the Mississippi Delta if it were to become widespread.