Apr. 12, 1924 
Brittle Straw and Other Abnormalities in Rye 
171 
The ash, starch, and pectin contents are not very different in the two samples. 
The high sugar content and higher pentosan content coincident with low crude 
fiber in the brittle plants indicate that the carbohydrates do not contribute to 
wall-forming material in the normal way. 
The methods used in the analysis of ash, starch, crude fiber, and pentosan 
were taken from the “ Methods of Analysis of the Association of Official Agri¬ 
cultural Chemists.” 2 The method used for the pectin determination was that 
Fig. 1.—Cross section of normal rye stem. X80 
reported by Carr6 and Haynes. 3 The sugars were determined by the picric acid 
method. 4 
Histological and microchemical examinations were made along with the 
chemical analysis. The microscopic appearance of cross sections of brittle 
and normal rye stems was quite different, as is shown in figures 1 and 2. While 
the depth of the sclerenchyma layer at the periphery of the stem was practically 
the same in the two samples, the thickness of the cell walls was strikingly less 
Fig. 2.—Cross section of “brittle” rye stem. X80 
in the brittle rye, as indicated in Table IV. Garber and Olsen found a similar 
condition associated with lodging in oats and rye. 5 
2 Association of Official Agricultural Chemists . official and tentative methods of analysis. As 
compiled by the Committee on Revision of Methods. Revised to Nov. 1,1919. 417 p., illus. Washington, 
D.C. 1920. 
* Carr£, M. H., and Haynes, D. the estimation of pectin as calcium pectate and the appli¬ 
cation OF THIS METHOD TO THE DETERMINATION OF THE SOLUBLE PECTIN IN APPLES. BiOChem. JOUT. 
16:60-69. 1922. 
4 Lewis, R. C., and Benedict, S. R. a method for the estimation of sugar in small quantities 
of BLOOD. Jour. Biol. Chem. 20: 61-72. 1915. (Modified 1923 by Willaman and Davison.) 
5 Garber, R. J., and Olsen, P. J. a study of the relation of some morphological characters 
to lodging in cereals. Jour. Amer. Soc. Agron. 11: 173-186, illus. 1919. 
