PLANT BREEDING 



189 



kind or of one row are thus detasseled, it is made probable that 

 pollen, if received at all by the ears of the detasseled stalks, 

 must come from another row or from another kind of corn. 

 The detasseling of alternate rows is a rather common way 

 of insuring cross-pollination. In most cases of hybridizing 

 with bisexual flowers it is necessary to carry out processes 

 similar to the following ones: 



1. Select the flower to be pollinated before it 

 opens or before its own pollen is mature. If it is 

 one of a cluster of flowers, as in the wheat and 

 the apple, remove from the cluster of the flowers 



all that are not to 

 be operated upon. 

 2. Open the re- 

 maining flowers 

 and remove the 

 stamens by taking 

 hold of the fila- 

 ments with fine 

 forceps, or cut 

 away all the sta- 

 mens at once, as 

 shown in figure 

 162. Keep the 

 flower or the en- 

 tire twig covered with a paper bag until the stigma is mature. 



3. When the stigma is mature, pollinate it with the desired 

 kind of pollen. This may be done with the finger tip or with 

 a camel's-hair brush or other implement. It is safer to take 

 pollen from a flower that has been kept covered with a paper 

 bag to keep off foreign pollen. 



4. Keep the pollinated flower covered with a paper bag 

 until the fruit has grown considerably. 



178. Plants grown from hybrid seeds. When seeds pro- 

 duced by hybridization are planted, the seedlings grown from 

 them may vary greatly in their vegetative characters, as size, 



Fig. 162. A peach flower prepared for hybridization 



A, flower cut round for removal of the stamens, with 

 the removed parts of the young flower showing above ; 



B, longitudinal section of a flower showing level () 



at which the cut was made in A 



