Submitted to: Entomological Society of America Annual Meeting North Central Branch
Publication Type: Abstract Only
Publication Acceptance Date: March 5, 2005
Publication Date: March 11, 2005
Citation: Behle, R.W. 2005. Evidence that cuphea does not support larval development of western corn rootworm larvae [abstract]. Entomological Society of America Annual Meeting North Central Branch. Abstract #D207. Technical Abstract: Large numbers of adult Western corn rootworms, Diabrotica virgifera virgifera LeConte, caught in emergence cages placed in replicated field plots planted to Cuphea spp. over successive years, suggests that rootworm larvae can successfully develop on this broad-leaf plant. To further study this unexpected observation, two buckets of topsoil were collected from each of four locations in the same research field located near Urbana, Illinois. Soil from each bucket was sieved through a number 4 sieve, then homogenized by tumbling in a cement mixer and stored in a refrigerator for 1 month. After storage, 1.3 kg soil (previously determined to average 12 eggs) was placed in each of 32 pots (155 mm standard). Half of the pots were planted to Cuphea (10 plants/pot) and the other half to corn (3 plants/pot). Destructive sampling at 6 and 8 weeks after planting consisted of manually picking through the soil and root mass to find rootworms. For pots planted to corn, 7 larvae, 9 pupae, and 1 adult were found in eight pots when sampled at 6 weeks; and one adult was found in eight pots sampled at eight weeks. No rootworms were found in the soil from plots planted to Cuphea. A final extraction of the soil for rootworm eggs found a total of 3 eggs from Cuphea pots and 1 egg from corn pots suggesting successful egg hatch in all pots. Thus, this experiment did not support the field observation that corn rootworm larvae could develop on Cuphea roots.