ANNUAL REPORT, 1941 9 



On areas of the plot where linae was applied, the sugar content of the fruits was 

 increased in some instances. This was true of blueberries and grapes, but not of 

 watermelons. 



The Absorption and Excretion of Potassium and Calcium by the Roots of 

 Barley in Different Solution Media and Changes in pH. (Walter S. Eisenmenger 

 and George Wenzel.) Determinations were made of the absorption and excre- 

 tion of potassium and calcium, by (barley) plants and excised root systems of 

 barley, from and into one-salt solutions of different concentrations, and into 

 distilled water. A study of the changes in hydrogen-ion concentration of the 

 solutions was also included. The salts used were acid potassium phosphate 

 (KH2PO4), and calcium nitrate (Ca(N03)2). The length of the experimental 

 period was 72 hours in all tests. 



The intensity of absorption and excretion increased with the length of the ex- 

 perimental period. In general the absorption increased rapidly after the first 

 24 hours, while the excretion increased slowly throughout. 



The reaction of the media was never stable in the presence of live root systems. 

 The pH values increased during the daylight hours and decreased somewhat 

 during the night. The continual change of pH values was, undoubtedly, tied up 

 with absorption and excretion phenomena of electrolytes, but to state that the 

 degree of change was absolutely proportional to the rates of absorption and ex- 

 cretion would imply the exclusion of buffer action and other controlling factors. 



The proportion of absorbable ions absorbed during a given period decreased 

 as the concentration of these ions in the solution decreased. In this way plants 

 can adapt themselves, to a considerable extent, to solutions of low concentration. 



For the first two days potassium was more firmly held by the roots than calcium, 

 after which calcium was excreted in larger amounts, but no considerable excre- 

 tion of either was observed. The excretion of ions into salt solutions was greater 

 than into distilled water. 



An equivalent absorption and excretion of calcium and potassium did not 

 take place, except for extremely short periods. 



The results with excised roots show that roots alone are not capable of a uniform 

 absorption of ions. 



Attention is called to the fact that energy exchanges are involved in the proc- 

 esses of absorption and excretion. Permeability and osmosis alone are inade- 

 quate to explain these phenomena in the living plant. 



Sunflowers and Their Possibilities. (Karol J. Kucinski and Walter S. Eisen- 

 menger.) This year's growing season was an exceptionally good one for sun- 

 flowers, which grew to maturity and formed very large seed heads. Seedings 

 of one seed per hill every 18 inches in 36-inch rows produced a yield of over two 

 tons per acre of well-formed large seeds. This yield is much larger than that 

 obtained in past years, indicating that a good corn-growing season is also a good 

 sunflower season. At the current wholesale market price of sunflower seed the 

 value per acre is about $225 to $250. This crop would seem to have great pos- 

 sibilities if grown commercially, even on some of our lands which have a high 

 per acre valuation. Since it is somewhat difficult during this present national 

 emergency to import from abroad as much sunflower seed as is necessary, it 

 might be feasible for some of our farmers to grow the crop commercially. 



The cil obtained from sunflower seed is very high in content of vitamins A 

 and D, but it is used in this country primarily as a drying oil in paints. In eastern 

 continental Europe the peasant population has always eaten the seed. It has 

 been thought by some scientists that this seemingly habit-forming practice of 

 eating the sunflower seed is an instinctive effort on the part of the individual to 

 supplement his usual deficient diet with the high nutritive contents of the seed. 



