CONTENTS 



PAOB 



delayed in plants, p. 15 ; Sex, p. 16 ; Difficulty of 

 control, p. 16 ; Seed an embryo, p. 16. 

 Examples of Improvement or Modification in Plants . 17 

 Examples of definite improvement, p. 18. 



Methods of Improvement 19 



Inducing variation, p. 19 ; Influence of environment, 

 p. 19; Change of seed, p. 20 ; Crossing, p. 21 ; 

 Selection, p. 21; Power of specific forms to repro- 

 duce themselves, p. 22 ; Importance of large num- 

 bers, p. 23. 



Plant Breeder's Advantage 23 



Practicums 24 



Collateral Reading 25 



CHAPTER III.— WHEAT. 



I. STRUCTURE. 



Relationships . 26 



Roots, p. 26 ; Culms, p. 27 ; Leaves, p. 29 ; Tiller- 

 ing, p. 29 ; Organs of reproduction, p. 30 ; The 

 true flower, p. 3 1 ; The spikelet, p. 3 1 ; The spike, 

 p. 32 ; The grain, p. ^^ ; The embryo, p. 34 ; The 

 endosperm, p. 35 ; Aleurone layer, p. 35 ; The bran, 

 p. 35 ; Physical properties, p. 37. 



II. COMPOSITION. 



Composition 3^ 



Water, p. 38 ; Ash, p. 39 ; Protein, p. 40 ; Gluten, 



p. 41 ; Gliadin, p. 42 ; Glutenin, p. 42. 



Relation of Weight per Bushel to Nitrogen Content . 42 



Influence of Environment on Composition of Grain , 44 



Germination 4^ 



