SELECTED BIBLIOGRAPHY 413 



Discussion Questions 



1. Suggest as many possible reasons as you can for the fact that different kinds 



of plants, growing in the same soil and under the same climatic conditions, 

 absorb various ions in different proportions. 



2. Can the mineral element requirements of a plant be judged from a chemical 



analysis of the plant? 



3. What are the soil factors which will influence the rate of absorption of ions 



bv the roots of plants? 



4. When plants are grown with their roots in a solution containing calcium 



nitrate the H-ion concentration of the solution usually shows a gradual 

 decrease. If ammonium sulfate is used as a source of nitrogen, however, 

 the solution usually increases in H-ion concentration. Explain. 



5. How would you attempt to show experimentally whether or not absorption 



of water and mineral salts by plants are largely independent processes? 



Suggested for Collateral Re.^ding 



Robinson, G. W. Soils, their origin, constitution and classification. D. Van 



Nostrand Co. New York. 1932. 

 Russell, E. J. Soil conditions and plant growth, 7th Ed. Longmans, Green 



and Co. London. 1937. 



Selected Bibliography 



Berr}', W. E., and F. C. Steward. The absorption and accumulation of solutes 

 by living plant cells. VI. The absorption of potassium bromide from 

 dilute solution by tissue froju various plant organs. Ann. Bot. 48: 395- 



410. 1934- , . 1 . 



Crafts, A. S., and T. C. Broyer. Migration of salts and zvater into xylem of 



the roots of higher plants. Amer. Jour. Bot. 25: 529-535- 1938. 

 Hoagland, D. R., and T. C. Broyer. General nature of the process of salt 



accumulation by roots with description of experimental methods. Plant 



Physiol. 11:471-507. 1936. 

 Hoagland, D. R., and A. R. Davis. The composition of the cell^ sap of the 



plant in relation to the absorption of ions. Jour. Gen. Physiol. 5 : 629- 



646. 1923. 

 Hoagland, D. R., and A. R. Davis. The intake and accumulation of elec- 

 trolytes by plant cells. Protoplasma 6: 610-626. 1929- 

 Jenny, H., and E, W. Cowan. The utilization of adsorbed ions by plants. 



Science 77: 394-396. I933. 

 Latshaw, W. L., and E. C. Miller. Elemental composition of the corn plant. 



Jour. Agric. Res. 27: 845-860. 1924. 

 Newton, J. D. The selective absorption of inorganic elements by various 



crop plants. Soil Sci. 26: 85-91. 1928. 

 Osterhout, W. J. V. The absorption of electrolytes in large plant cells. 



Bot. Rev. 2: 283-315. 1936. 

 Prevot, P., and F, C. Steward. Salient features of the root system relative 



to the problem of salt absorption. Plant Physiol. 11 : 509-534. 1936. 



