Several backcross progenies involving genes located on chromosomes 3 and 7 were grown in 1941. They were not reported in the last News Letter as the data had not been summarized, hence they are reported now. A few additional backcross progenies were grown during the past season and are reported. Cold, wet weather following planting resulted in very poor stands in both seasons, but it is felt that the segregations obtained are not sufficiently distorted to modify gene order.

1. Backcrosses involving genes on chromosome 7.

 

gl ij bd7
+  +  +
0 1 2 1-2 Total
69  53 4  4 68  26 4  2  
122 8 94 6 230

 

Linear order and map distances are: gl - 6.1 - ij - 43.5 - bd7

(500 seeds were planted, 46.0% produced mature plants.)

 

gl sl ij
+  +  +
0 1 2 1-2 Total
268  182 32  52 2  5 0  2  
450 84 7 2 543

 

Linear order and map distances are: gl - 15.8 - sl - 1.7 - ij

(1,000 seeds planted, 54.3% produced mature plants.)

 

O2 ra gl ij
+  +  +  +
0 1 2 3 1-2 1-3 2-3 1-2-3 Total
273  213 24  28 6  3 49  56 1  1 5  7 0  2 1  0  
486 52 9 105 2 12 2 1 669

 

Linear order and map distances are: O2 - 10.0 - ra - 2.1 - gl - 17.9 - ij

(1,000 seeds planted, 66.9% produced mature plants.)

 

O2  ij  bd7
+   +   +
0 1 2 1-2 Total
69  56 24  44 38  44 7  17  
125 68 82 24 299

 

Linear order and map distances are: O2 - 30.8 - ij - 35.5 - bd7

(500 seeds were planted, 59.8% produced mature plants.)