W. J. Reid

Susceptibility of certain coleopterous larvae to the DD-136 nematode

Abstract In laboratory cages the nematode DD-136 was highly pathogenic to larvae of the banded cucumber beetle, Diabrotica balteata , but only slightly so to larvae of the southern potato wireworm, Conoderus falli . In field drum plots, the nematode caused as much as 76% mortality of the Diabrotica larvae; residual activity was increased by shading the soil. Higher dosages were more effective than lower ones. However, three applications of the nematode to small field plots of sweet potatoes did not give adequate protection against the total insect complex. Bioassays of soil from these plots indicated that the nematode produced high initial infection in D. balteata larvae but declined rapidly in effectiveness thereafter.