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TEXTBOOK OF BOTANY 



SPERMSi 



Fig. 214. Diagram illustrating the derivation of the chromosome complement of the 

 triple fusion nucleus and the endosperm cells resulting in xenia. 



fusion nucleus has a double set of these chromosomes. With this one 

 exception, the fertilized egg and triple-fusion nucleus in the same embryo 

 sac have the same chromosome complement. 



Some of the factors in these chromosomes specifically affect the 

 processes in the endosperms, such as the formation of starch, dextrin. 



Fig. 215. Ear of Stowell's Evergreen sweet com from an open pollinated plant. 

 The development of the endosperm of some of the grains was influenced by 

 sperms from waxy corn, and black Mexican sweet corn growing nearby. Photo 

 by G. W. Blaydes. 



protein, and pigment. It is often observed that when brown-, blue-, or 

 yellow-grained corn is growing near white-grained com, a few colored 

 grains of corn appear on the ears of white com, but white grains do not 

 appear upon the ears of colored corn this same season (Fig. 215). 

 Similarly grains of starchy corn appear on the ears of sweet corn, and 

 grains of field com appear on the ears of pop corn. 



