FACTORS AFFECTING SALT ABSORPTION 



69 



T3 



a> 



^ 

 o 

 in 

 Xk 

 O 



(U 

 D 



jr 



Q. 

 (/> 

 O 



.c 



a. 



k- 

 o 



o 



o 

 o 



10 20 30 40 50 60 70 80 90 100 110 .120 

 Time, days 



-Lighf- 



-Dork- 



>> 



D 

 ^^ 



E 

 u 



o 



0) 



o 



3 



o 



o 



01 2345678 



Time, days 



Fig. 24. Growth and salt absorption 



a. Growth (O— O) and phosphate absorption ( — ) in tobacco (T) and 



potato (P). Redrawn from Dean and Fried (1953); b. Growth ( — ) and 



phosphate absorption ( — ) by maize plants grown at first in light and then 



transferred to darkness (redrawn from Alberda, 1948). 



inorganic elements they contain (Fig. 24a). Any treatment which 

 reduces growth causes a corresponding decrease in the absorption 

 of saUs (Fig. 24b). The importance of locahzed growth in controlling 

 the redistribution of salts within vascular plants, is discussed below 

 (Chapter 7, pp. 125-127). 



5. Symbiosis 



Root systems of many plants have fungi associated with them to 



6 M.S.A.P. 



