PLANT PROPAGATION 101 



grain at its opposite end. Does the plumule 

 develop from the blunt end or the pointed end ? 

 3. Make a sketch of the seedling (X 2) and label grain of 

 corn, scar where grain was attached to the cob, 

 stem of plumule, sheath leaf, unfolding leaf, main 

 root, rootlets, soil line. 



B. Corn grain just sprouting. 



1. Examine a corn grain that has just sprouted. Recall 



to mind the end of the grain from which the main 

 root grew. (If you are not sure, look at your 

 drawing, or better yet the seedling.) 



a. What part of the little corn plant breaks through the 



covering first? 



b. What other part of the embryo shows signs of growth? 



2. Remove the thin covering from the grain, and observe 



an oval body embedded in the corn grain. This is 

 the little corn plant or embryo. How does the 

 embryo differ in color from the rest of the grain? 



3. The oval-shaped body from which the root and plumule 



seem to spring in the grain of corn is called the 

 cotyledon. The remainder of the grain is endo- 

 sperm, which is the food material for the develop- 

 ment of the embryo. Make a sketch of the seed- 

 ling at this stage (X2) and label single cotyledon, 

 plumule, endosperm or food material, main root. 



C. Corn grain. 



1. Very carefully scrape away a little of the surface of the 



cotyledon of a dry or soaked grain till the other 

 parts of the little plant or embryo come into view. 

 Make out the plumule and main root. 

 Sketch the corn grain and label cotyledon, plumule, 

 tiny root, food material around the plant (endo- 

 sperm). 



2. Cut a corn grain in such a way as to divide the embryo 



and endosperm lengthwise in half. Put one half in 

 iodine. Where in the corn grain is starch pres- 

 ent? Where is it absent? 



