The use of autoradiography in the indentification of selected bacteria in the European corn borer

AbstractScientists trying to find biological controls for insect pests are hamperedd by the absence of rapid methods for screening organisms such as bacteria for potential pathogenicity. An organism must grow in the gut of the insect to be pathogenic. By using radioisotopes as tracers a quick method of screening potential insect pathogens may be developed.Escherichia coli and Sarcina flava were used as known nonpathogens and Bacillus thuringiensis was used as a known pathogen. In this work an attempt was made to verify the presence of bacteria in specific tissues of the insects.European corn borer larvae were fed 1-C14 palmitic acid and labeled E. coli, S. flava and B. thuringiensis. Parasaggital sections were made of the corn borers and radioautograms were made of the sections. Grain counts over a 2,000 u2 area were made of various tissues and compared.There was a statistically significant difference in the distribution of label in corn borer larvae fed labeled bacteria as compared to corn borers fed 1-C14 palmitic acid. Label tended to incorporate into fatty tissue in the corn borers.If this technique can be used to positively demonstrate the establishment of selected bacteria in the gut of the insect then it may be possible to use such methods to screen for potential insect pathogens and give insight into the mechanisms which result in the death of insects.Ball State UniversityMuncie, IN 47306Thesis (M.S.)--Ball State University, 1971