Lecture 5 —125— Artificial Media 



do and how the system operates. If I have succeeded 

 in these lectures in convincing you that research in 

 Plant Nutrition has made a useful beginning in satisfy- 

 ing this curiosity, I shall be content. 



REFERENCES :- 



Arnon, D. I. and Hoagland, D. R. A comparison of water- 

 culture and soil as media for crop production. Science 89: 



512-514, 1939. .^ . , 

 , . Crop production in artificial culture 



solutions and in soils with special reference to factors 

 influencing yields and absorption of inorganic nutrients. 

 Soil Science 50: 463-485, 1940. 



, Fratzke, W. E. and Johnson, C. M. Hydrogen ion 



concentration in relation to absorption of inorganic nutri- 

 ents by higher plants. Plant Physiology 17: 515-524, 1942. 

 and Johnson, C. M. Influence of hydrogen ion con- 



centration on the growth of high plants under controlled 

 conditions. Plant Physiology 17: 525-539, 1942. 

 Barker, H. A. and Broyer, T. C. Notes on the influence of 

 microorganisms on growth of squash plants in water cul- 

 ture, with particular reference to manganese nutrition. 

 Soil Science 53: 467-477, 1942. 

 COLLANDER, RuNAR. Selective absorption of cations by higher 



plants. Plant Physiology 16: 691-720, 1941. 

 Comber, N. M. The availability of plant food. A modification 

 of the present hypothesis. Journal Agricultural Science 12 : 

 363-369, 1922. 

 Hoagland, D. R. and Arnon, D. I. Physiological aspects of 

 availability of nutrients for plant growth. Soil Science 51 : 

 431-444, 1941. 

 Jenny, H. and Overstreet, R. Cation interchange between 

 plant roots and soil colloids. Soil Science 47 : 257-272, 1939. 



, . Surface migration of ions and contact 



exchange. Journal Physical Chemistry 43: 1185-1196, 1939. 

 Nightingale, G. T. Nitrate and carbohydrate reserves in 

 relation to nitrogen nutrition of pineapple. Botanical 

 Gazette 103: 409-456, 1942. 

 Overstreet, R. and Jenny, H. Studies pertaining to the cation 

 mechanism of plants in soil. Proc. Soil Science Soc. of 

 America 4: 125-130, 1939. 

 Spencer, Ernest L. Specific biological activity of tobacco vines 

 as influenced by age of lesion and nitrogen supply. Plant 

 Physiology 17: 210-222, 1942. 

 Trelease, S. F. and Trelease, Helen M. Changes in hydrogen- 

 ion concentration of culture solutions containing nitrate 

 and ammonium nitrogen. Amer. Jour. Bot. 22: 520-542, 

 1935. 

 Vlamis, James. Studies on salt absorption by the rice plant. 

 Thesis for Ph.D. degree. University of California, 1941. 



