Reproductive Biology and Control ofSolanum dimidiatumandSolanum carolinense

Abstract

Studies were conducted to investigate the reproductive biology and herbicide response of horsenettle (Solanum carolinenseL. # SOLCA) and robust horsenettle (Solanum dimidiatumRaf. # SOLDM) that are common in peanut (Arachis hypogaeaL.) production. Of these two species, horsenettle had a higher rate of seed germination, greater ability for seedling establishment in a competitive situation (pasture), greater ability to regenerate from smaller root fragments, and greater ability to regenerate from progressively greater depths in soil. Horsenettle was relatively more sensitive to glyphosate [N-(phosphonomethyl)glycine] (1.1 and 2.2 ai kg/ha), propylene glycol butyl ether esters of 2,4-D [(2,4-dichlorophenoxy)acetic acid] (0.8 and 1.7 ae kg/ha), and the ethanolamine salt of 2,4-D (1.7 ae kg/ha) than robust horsenettle. Conversely, robust horsenettle was more sensitive to dicamba [3,6-dichloro-2-methoxybenzoic acid)] (0.3 and 0.6 ae kg/ha). In a field study, dicamba applied annually in July or August for 2 yr at a rate of at least 1.1 kg/ha controlled 92% or more.