Insects, nematodes, and pathogens associated with horsenettle (Solanum carolinese) in Bermudagrass (Cynodon dactylon) pastures

Horsenettle is a deep-rooted perennial weed that cannot be easily controlled by mechanical means or by a single chemical application. A study was conducted at two sites for two consecutive years to identify biological factors that might limit its growth. Insects, nematodes, and plant pathogens were collected from horsenettle growing in bermudagrass pastures. The insects most commonly found included the Colorado potato beetle and the eggplant flea beetle. An unidentified lepidopteron, family Gelechiidae, was found at very low frequency as pupae in hollow leaf chambers constructed at the apices of flowering meristems. Infested apices bore no fruit. Seven genera of nematodes were found in the soil at both sites, but only very low numbers of lesion nematodes were recovered from horsenettle roots, and these had caused little damage. Root rot was observed under wet soil conditions on plants damaged by trampling. A downy mildew was prevalent at both sites in both years in October.