Specificity of Disonycha glabrata (Coleoptera: Chrysomelidae) in caruru and sweet potato genotypes

This study aimed to test the feeding preference of Disonycha glabrata (Fabr.) (Coleoptera: Chrysomelidae) between amaranth plants and different genotypes of sweet potato in field and laboratory. Disonycha glabrata demonstrated specificity to the amaranth plant in multiple-choice tests, gained weight with this diet in nonchoice tests and it was found, under field conditions, constantly on this weed host compared with the ten genotypes of sweet potato evaluated. The results indicate that this chrysomelid might be a future candidate for biological control programs of amaranth plants, although further research should be conducted to assess the real potential of this insect as a biological control agent of weeds.