CHAPTER IV 

 COMPARATIVE STUDY OF CEREALS 



IN the germination of cereals some interesting comparisons are 

 noted. First, the young roots appear, then the plumule or young 

 plant. In corn, wheat, and rye the young plant arises directly from 

 the germ, but in oats and barley the grain is enclosed in a husk and 

 the young plant grows under the husk, emerging at the opposite end 

 of the grain (Fig. 8). 



FIG. 8. Germinating oats, on left, and barley, on right. Note that oats has three tempo- 

 rary roots and barley six (compare with Fig. 5) . 



The young roots are usually 3 in number in corn, wheat, and oats, 

 but usually 4 in rye and 5 or 6 in barley. The number of roots on 

 germination is not exact ; for example, in corn the number may vary 

 from 2 to 5, but is usually 3. 



Temporary and Permanent Roots. The first roots emerging 

 are called temporary roots. They only assist the young plant while 

 it is becoming established, and probably supply water mostly as the 

 young plant at first lives largely on the stored-up food in the seed. 



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