DETECTION OF TOXIC METABOLITES IN THE HEMOLYMPH OF BEAUVERIA-BASSIANA INFECTED SPODOPTERA-EXIGUA LARVAE

Highly active metabolites have been detected in the hemolymph of the lepidopteran Spodoptera exigua infected with the mycopathogen, Beauveria bassiana. A combination of phenyl sepharose and CM ion exchange chromatography was utilized to extract the active metabolites from infected hemolymph samples. The active in vivo metabolites, having a molecular mass greater than 10 KDa, were thermolabile and were inactivated by proteinase K. These metabolites were characterized by their ability to disrupt metamorphosis, killing treated larvae at the wandering or pupal stage. Additionally, injection of S. exigua larvae with 'active' samples caused a reduction in the number of filopodial-producing hemocytes. The biological activities and biochemical properties suggest that novel compounds are produced during B. bassiana mycosis.