EFFECTS OF MUTILATING THE SEEDS OF CORN. 3 



the food reserves of the seed as follows: (a) Dwarfing the plants; 



(b) causing very apparent morphological modifications in the leaves; 



(c) causing a precocious but sparse flowering, in some instances the 

 only flowering, in others followed by a second flowering at the normal 

 period; and (d) causing frequent sexual anomalies in the course of 

 the first flowering. 



Andronescu (1) conducted experiments with maize in the labora- 

 tory and in the field. In the laboratory he dissected out the em- 

 bryos, detaching them from the scutella, and succeeded in germi- 

 nating them upon various nutrient solutions. He found that "the 

 stem produced was the expansion of the mesocotyl and the elongation 

 of the plumule sheath. One principal and two secondary roots, very 

 poorly developed, were produced. In no case was the plumule able 

 to split its sheath. " 



In the field experiments the embryos were not detached from the 

 scutella and the plants were grown to maturity. The stalks from 

 the embryos were shorter, of smaller diameter, and of fewer inter- 

 nodes than the stalks from the entire seeds. In general, the ears of 

 the stalks from embryos were borne at lower nodes than the ears of 

 the stalks from entire seeds. The ears from both the control and the 

 test plants were imperfectly developed because of unfavorable weather 

 during the growing season. No comparison of yield is shown. 



The experiments that have been reviewed have dealt principally 

 with plants other than corn; they have been conducted largely in 

 the laboratory or greenhouse and frequently have not extended to 

 the maturity of the plants. In some of the experiments the seed has 

 been sown in the greenhouse and the plants later transferred to the 

 field. These experiments would not be entirely representative of 

 field conditions. In those that have been conducted under field con- 

 ditions, corn either has not been among the species worked with or 

 where it has been included the data obtained are incomplete. 



EXPERIMENTS ON THE EFFECTS OF MUTILATION OF THE SEED COATS 



AND ENDOSPERMS. 



The experiments reported in this bulletin, with the exception of 

 those on the effect of mutilation of the embryo, were entirely under 

 field conditions. The purpose was to determine the effects upon 

 growth and productiveness that may be expected in a general way 

 to result from the use of seed which from various causes is deficient 

 in food reserves. These experiments are of additional interest be- 

 cause of the data they furnish upon the influence of the physiological 

 condition of the seed in predetermining the subsequent development 

 of the plant. 3 



3 This subject has been interestingly discussed and reviewed by Kidd and West, Physiological Predeter- 

 mination, in Annals of Applied Biology, v. 5 and 6, 1918, 1919. 



