PRINCIPAL INVESTIGATOR (S ): R. C. von Borstel, R. H. Smith, Anna R. Whiting, 



and D. S. Grosch 



EXPERIMENT TITLE/NUMBER : Mutational and Physiologic Responses of Habrobracon 



in Biosatellite II, P-1079 



PROGRAM/MISSION : Biosatellite II 



CLASSIFICATION : Animal, Microorganism - Parasitic wasp ( Habrobracon 

 iuglandis ) . Brine shrimp cysts ( Artemia salina ) . 

 Microorganism ( Saccharomvces c erevisiae ) 



DISCIPLINE(S) : Radiobiology, Genetics, Behavioral science 



OBJECTIVES : To survey mature sperm and all different stages of oogenesis for 

 mutations (particularly dominant lethality), recessive lethal and visible 

 mutation frequencies, and inherited partial sterility under the combined 

 conditions of radiation and weightlessness. 



PROTOCOL : M 8i e a nd female wasps were irradiated preflight, inflight, or not 

 at all with Sr at 4000 R, 2000 R, 1000 R, 500 R or R. Thirty parameters 

 of genetic, mutational, biochemical, behavioral, and physiological character 

 were measured. Artemia salina cysts were used since they are sensitive to 

 vibration. Saccharomvces cerevisiae were used to detect scattered radiation. 



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 EQUIPMENT : Habrobracon flight containers, Sr source, LiF powder, glass rod 



dosimeters. 



RESULTS : Spaceflight effects were enhancement of fecundity and hatchability 

 of primitive and transitional oogonia, disorientation of male mating behavior, 

 increased life span of females and decreased xanthine dehydrogenase activity 

 in males. The effects of radiation were decreased hatchability and enhanced 

 fecundity of eggs. The only mutagenic effect found was a threefold 

 enhancement of the recessive lethal mutation frequency in the nonirradiated 

 sperm in the orbited males. No difference was found in intragenic or 

 intergenic recombination endpoints comparing flight and ground control 

 Saccharomvces . The Artemia cysts were not influenced by spaceflight or gamma 

 radiation received inflight. 



CONCLUSIONS : The enhancement of spontaneous recessive lethal frequency in 

 sperm was induced by some factor of the flight profile other than 

 weightlessness. The excess of deaths found among the offspring from females 

 flown might have been from a mixture of chromosome imbalance phenomena and 

 recessive lethal mutations induced by the spaceflight conditions. The 

 increased fertilizing capacity appeared to be an enhancing effect of radiation 

 combined with weightlessness. The strong trend for enhanced emergence from 

 Artemia cysts might have been caused by vibration. 



PUBLICATIONS : 226, 227, 228, 229, 230, 545, 546, 547, 546, 549 



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