lOO 



BOTANY OF CROP PLANTS 



embryo. Along the side of the grain, facing the palet, is a 

 groove or furrow. This groove marks the region of attach- 

 ment of seed to ovary. The position of the embryo may be 

 seen easily at the base of the grain. Fig. 34 shows a cross- 



FiG. 34. — Common wheat (Triticum aestivum). ^4, grain, groove side; B, 

 grain, embryo side; C, cross-section of grain through the embryo; D, cross- 

 section of grain beyond the embryo. 



— pericarp 



Pig. 35. — Microscopic section of wheat grain. 



section of a mature grain of wheat through the embryo 

 region. The three primary roots are seen in section. 



In a cross-section of a mature wheat grain, cut at right 

 angles to its length, so as not to include the embryo, the 

 following layers may be recognized (Fig. 35) : 



