INDEX 



325 



Nilsson, inheritance in potatoes, 221 

 oat, classification, 95 

 potato, degeneracy in, 232 

 rye, self-pollination, 40 

 Nilsson-Ehle, oat inheritance, 92, 



93, 95, 96, 97, 133 

 oats, false wild, 97 

 wheat, disease resistance, 85 

 seed characters in, 82 

 spike density in, 81 

 winter-hardiness, 87 

 Norton, A. sterilis, oats, 90 



rust resistance, asparagus, 254 

 time of blooming, oats, 71 







Oats, awn development, 90 



color of lemma, 93 



color of stem, 92 



disease resistance, 95 



false wild, 97 



improvement by crossing, 133 



linkage in, 97 



natural crosses, 36 



open vs. side panicle, 95 



origin of, 90 



pubescence on grain, 94 



selection in, 129, 130, 131 



size characters, 96 



species groups, 89 



yellow factor, 92 

 Oliver, crossing methods, 71 

 Olson, Bull and Hayes, ear charac- 

 ters and yield, maize, 198 

 Origin and development of crops, 1 

 Orton, cotton, wilt resistance, 177 



cowpea, resistance and wilt and 

 root-knot, 144 



watermelon, wilt resistance, 258 



Pea, classification of, 236 



genetic factors in, 240 



inheritance in, 236 



linkage in, 241 



natural crosses, 38 



structure of flower, 237 

 Pear, self -sterility in, 269 

 Pearl and Miner, probable errors, 56 

 Pepper, characters, 246 



inheritance in, 247 

 Piper, alfalfa, origin and species, 215 



cowpea, breeding, 146 



cowpea, origin of, 143 



pea, natural crosses, 38 



sorghum species, 178 



soybeans, natural crosses, 39 

 Piper and Morse, origin of soybean, 



146 

 Piper and others, alfalfa pollination, 



40, 216 



Plant breeding, development of art, 

 2 



relation of biological principles 



to, 8 



Plum, self-sterility in, 269 

 Pollination, artificial crosses, oats, 71 



artificial self-pollination, 67 



depollination with water, 73 



tools for, 73 



Pope, pollination of crop plants, 34 

 Price, cabbage, self -sterility, 251 



inheritance in cabbage, 251 

 Price and Drinkard, tomato inheri- 

 tance, 245 



Pridham, oat crosses, 36, 93 

 Probable error, use of, 56 



in eliminating strains, 57 



pairing method of obtaining, 57 

 Pure line theory, 11, 120, 121 



Pammel, crosses in cucurbits, 256 

 Parker, disease resistance in oats, 95 



spike density in wheat, 81 

 Parnell and others, inheritance in 

 rice, 109 



natural crosses in rice, 37 



Quanjer, diseases in potatoes, 231 



R 



Radish, origin, inheritance, breed- 

 ing, 249 

 Raspberry, inheritance, 272 



