GREGORY: EFFICACY OF MUTATION BREEDING 471 



Table 2. — Effect of Radiation Upon F-> Progeny Means in Percentage of the Mean 

 of All Treatments and Crosses, Fruit Yield. 



Treatments 

 Cross 



P PX F FX Cross x 



% % ' % % % 



Cross I: 



Bl. 1 102.0 98.8 101.4 96.2 99.6 



Bl. 2 101.7 95.0 98.3 103.3 



Cross II: 



Bl. 1 96.4 94.5 103.2 96.3 100.5 



Bl. 2 106.9 97.7 108.1 101.5 



Cross III: 



Bl. 1 100.5 93.6 105.4 103.7 99.9 



Bl. 2 102.5 89.5 106.4 97.5 



x 101.7 94.9 103.8 99.8 100.0 



significance for the plant breeder. The F 2 genotypic standard devia- 

 tions for individual families are presented for each treatment in 



Table 3. — Mean Yield (x) of F 2 Plant Progenies and Genotypic Standard 

 Deviations (sg) in Pounds of Dry Fruit. 



Treatment 

 Cross P PX F FX 



X SG X Sq X SQ X SQ 



Cross I: 



Block 1 2.38 0.06 2.31 0.31 2.37 0.22 2.25 0.36 



2 2.37 0.00 2.22 0.40 2.29 0.19 2.41 0.24 



Cross II: 



Block 1 2.25 0.00 2.21 0.27 2.41 0.22 2.25 0.32 



2 2.50 0.00 2.28 0.19 2.52 0.16 2.37 0.39 



Cross III: 



Block 1 2.35 0.00 2.19 0.26 2.46 0.22 2.42 0.27 



2 2.39 0.04 2.09 0.22 2.48 0.23 2.28 0.27 



Grand x 2.37 2.21 2.42 2.33 



Av. s G 0.02 0.27 0.21 0.31 



