DAILY VARIATION OF WATER AND DRY MATTER IN 

 THE LEAVES OF CORN AND THE SORGHUMS 



By Edwin C. Miller,^ 



Assistant Plant Physiologist, Department of Botany, 

 Kansas Agricultural Experiment Station 



INTRODUCTION 



In connection with the study of the water relations of corn and the 

 nonsaccharin sorghums previously reported by the writer,^ it was 

 thought advisable to determine the daily variation of the water and 

 dry matter in the leaves of these plants. A knowledge of the variation 

 of the water in the leaves should throw some light on the relative ability 

 of these plants to absorb water from the soil and to transport it to 

 regions of loss from transpiration, while a study of the daily variation 

 of dry matter in the leaves would permit a comparison of the relative 

 power of the plants to manufacture food under different climatic condi- 

 tions. The experiments herein reported were conducted during the 

 summers of 1914, 1915, and 1916 at the State branch Experiment 

 Station at Garden City, Kans. 



EXPERIMENTAL METHODS 

 CULTURAL METHODS 



The plants used in these experiments were Pride of Saline corn (Zea 

 mays), Blackhull kafir {Andropogon sorghutn), and Dwarf milo {A. sor- 

 ghum). In 1 91 4 and 191 5 the plants were grown in alternate rows on 

 the same plot, while in 191 6 the experiments were made with plants 

 grown on a series of one-twentieth-acre plots. The plants were 

 grown in a sandy-loam soil that had been fall-plowed and irrigated 

 with approximately 8 inches of water. The crops were surface-planted 

 in rows 44 inches apart. After the plants were a few inches high 

 the corn was thinned to a distance of 2 feet between the plants, 

 Blackhull kafir to i}4 feet, and the Dwarf milo to i foot. The plots 

 were scraped with a hoe to keep the weeds down, but no other cultivation 

 was given during the growing season. They received no water after 

 the fall irrigation, except that which came from the rainfall. 



1 Acknowledgments are due Mr. J. L. Jacobson for his aid in collecting material in 1914 and to Mr. W. B. 

 Coffman for his general assistance in all phases of this work. 



2 Miller, E. C. comparative study of the root systems and leaf areas of corn and the 

 SORGHUMS. In Jour. Agr. Research, v. 6, no. 9, p. 311-332, 3 fig., pi. 38-44. 1916. Literature cited, p. 331. 



. RELATIVE WATER REQlTiREMENT OP CORN AND THE SORGHUMS. In Jour. Agr. Research, V. 



6, no. 13, p. 473-484, I fig., pi. 70-72. 1916. 



Journal of Agricultural Research, Vol. X, No. i 



Washington, D. C. July 2 1917 



in Key No. Kans. — 6 



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