Field Assessment of Greenbug (Homoptera: Aphididae) Demography on Corn

Abstract

Biotype E green bugs from populations maintained either on Corn, Zea mays L., or grain sorghum, Sorghum bicolor (L.) Moench., were studied to determine their ability to use Corn as a host in the field. Two Corn germplasm accessions (‘Antigua’ and OH-45), two commercial Corn hybrids (AGRIPRO-AP670and ASGROW/OS GOLD-2570), one susceptible grain sorghum (NC+630x), and two resistant sorghums (PI264453 and PI266965) were used. Daily mortality and fecundity schedules were measured, and demographic statistics were calculated. In general, longevity was greater for Corn-reared than for sorghum-reared greenbugs. All life history measures indicated that green bugs did as well on ‘Antigua’ Corn as on sorghum. However, of 64 greenbugs tested on OH-45 and ASGROW/OS GOLD-2570, only 1 and 6, respectively, survived to adulthood. Development time was significantly longer on OH-45, AGRIPRO-AP670, and ASGROW/OS GOLD-2570 for the first, second, and third instars, but not the fourth. This supports early greenhouse studies suggesting that green bugs can physiologically adapt to a new host. These results indicate that greenbugs can develop and reproduce to some extent on commercial Corn hybrids in the field, but not as well as suggested by greenhouse studies.