311 



with spores. An optimum spore dose and larval age at time of inocula. n, 

 exists for each pathogen. Infected adults emerge, live a short time, and are 

 harvested for optimum spore production. Production of the two pathogens is 

 compared, with Glugea gasti producing more spores per insect and thus having a 

 much lower cost. The method shows that mass production In vivo of a protozoan 

 pathogen can be done when large numbers of the host insect can be economically 

 grown. The pathogens were produced to support. 5 years of field testing. 



605. ; Bell, M. R.; and Daum, R. J. 1967. Suspension of microorganisms 



in a thixotropic solution. J. Invertebr. Pathol. 9: 70-77. 

 The rapid settling of microorganisms in suspensions introduces considerable 

 variation in the number of spores or particles dispensed, and this difference 

 Is often great enough to prevent administration of accurate doses. Because of 

 their thixotropic characteristics, solutions of hydroxyethyl cellulose of proper 

 viscosity and body v/ere used successfully to suspend spores of Mattesia grandis . 

 Since the spores did not settle in the syringe or needle, accurate doese could 

 be administered. 



606. ; Bell, M. R. ; and lIcReynolds, G. B. 1971. In vitro primary culture of 



embryonic cells from the boll weevil, Anthonomus grandis . J. Invertebr. 



• *• 



Pathol. 17: 81-86. 



*- 

 When embryonic cells of boll weevils, Anthonomus grandis , were grown in primary 



cultures, large aggregates of cells developed the first week, pulsing actions 



were strong, and multiplication occurred. Then for 4-7 weeks, the tissues grew 



unattached, formed large aggregates, and continued to pulse arid enlarge. 



Characteristically, the tissure developed spherical, membranous outgrowths, and 



cells developed peripherally and became multilayered; possibly, they possess 



an interior membrane. These latter growths resembled midgut cells. 



