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

Highly active metabolites have been detected in the hemolymph of the l epidopteran Spodoptera exigua infected with the mycopathogen, Beauveri a bassiana. A combination of phenyl sepharose and CM ion exchange chro matography was utilized to extract the active metabolites from infecte d hemolymph samples. The active in vivo metabolites, having a molecula r 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 pup al stage. Additionally, injection of S. exigua larvae with 'active' sa mples caused a reduction in the number of filopodial-producing hemocyt es. The biological activities and biochemical properties suggest that novel compounds are produced during B. bassiana mycosis.