PRINCIPAL INVESTIGATOR (S ): Charles J. Lyon 



EXPERIMENT TITLE/NUMBER : Growth Physiology of the Wheat Seedling in Space, 



P-1096 



PROGRAM/ MISSION : Biosatellite II 



CLASSIFICATION : Plant - Wheat seedlings (Triticum vulgare) 



DISCIPLINE(S) : Behavioral science, Cell biology 



OBJECTIVES : To determine whether seeds would produce normal seedlings, change 

 orientation, rate of growth, or germination in weightlessness. 



PROTOCOL : Seventy-eight wheat seeds weighing 38-39 mg were used in both the 

 flight package and Earth controls. The seeds were surface-sterilized in 0.05% 

 HgCl„ and soaked for 3 hours in distilled water at 95 F. The seedlings were 

 placed in polycarbonate stalks containing wet vermiculite. Gas samples were 

 taken and the lids were sealed. All growth took place in the dark. Angle 

 measurements were made to record root orientation. 



EQUIPMENT : Experiment package, photographic equipment. 



RESULTS : Growth physiology of wheat seed germination and the development of 

 wheat seedlings in their early stages were not disturbed sufficiently by the 

 absence of gravity to be reflected in growth rates or external morphology of 

 roots and coleoptiles. 



CONCLUSIONS : The apparent lack of disturbance of the basic metabolic 

 processes which supply the energy for normal growth indicates the independence 

 from gravitational force of certain organelles which carry key enzymes to the 

 sites of energy release and use. Weightlessness had no measurable effects on 

 the endogenous mechanisms for production and distribution of the growth 

 hormone, auxin. 



PUBLICATIONS : 363, 364, 365, 366 



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