EXERCISE 18 

 THE EARLY DEVELOPMENT OF THE CORN PLANT 



Object. To study the germination of the corn kernel 

 and the early growth and development of the corn 

 plant. 



Explanation. The kernel of corn incloses a living plant 

 in the dormant stage. The germ is the living part of the 

 kernel from which the shoot and roots develop. When 

 the kernel or seed is placed in the soil under proper con- 

 ditions of moisture and temperature, it absorbs moisture and 

 begins to grow. The food for the young plantlet is fur- 

 nished by the endosperm until the root system becomes 

 established. 



When the kernel of corn germinates, it sends out four 

 temporary roots. The largest of the four roots grows 

 directly out from the tip end of the germ. The other three 

 roots grow out where the main root and shoot are attached 

 to the kernel. Just above these three roots a little swelling 

 appears, and from this point the permanent root system 

 develops. The permanent root system develops about the 

 same distance from the surface of the soil regardless of the 

 depth of planting. 



Equipment. 1. Corn plants one, two, three, and four 

 weeks old, seeded one inch deep. 



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