2. Endosperm characteristics with Su1 Su2 and Du

 

For the past several seasons we have attempted to isolate and recognize the tvelve true breeding genotypes involving the three loci Su suam su, Su2 su2, and Du du. It is believed that all twelve stocks have now been isolated although final tests have not been ccmpleted. It appears to us at present that three testers will distinguish between the stocks. The following reactions are expected:

 

Genotype to be identified

Selfed appearance

su2

Appearance on
Female Tester Stock

suam du

su du

 

 

 

 

 

Su Su2 Du

Dent

Dent

Dent Translucent

Dent

 

 

 

 

 

Su Su2 du

Dent

Dent

Slightly wrinkled

Dent

 

 

 

 

 

Su Su2 Du

Dull surface

Dull surface

Dent

Dent

 

 

 

 

 

Su su2 du

Translucent Slightly wrinkled

Dull surface

Translucent Slightly wrinkled

Dent

 

 

 

 

 

suam Su2 Du

Dent

Dent

Dent

Semi opaque Slightly wrinkled

 

 

 

 

 

suam Su2 du

Translucent Wrinkled

Dent

Translucent Wrinkled

Translucent Wrinkled

 

 

 

 

 

suam su2 Du

Translucent Wrinkled

Dull surface

Dent

Translucent Slightly wrinkled

 

 

 

 

 

suam su2 du

Translucent Wrinkled

Dull surface

Translucent Wrinkled

Translucent Wrinkled

 

 

 

 

 

su Su2 Du

Strongly wrinkled

Dent

Dent

Strongly wrinkled

 

 

 

 

 

su Su2 du

Strongly wrinkled

Dent

Translucent Wrinkled

Strongly wrinkled

 

 

 

 

 

su su2 Du

Strongly wrinkled

Dull surface

Dent to Slightly wrinkled

Strongly wrinkled

 

 

 

 

 

su su2 du

Strongly wrinkled

Slightly wrinkled

Translucent wrinkled

Strongly wrinkled

 

During the past season, the 64 possible endosperm genotypes involving Su su, Su2 su2 and Du du were produced and are in the process of being analyzed for amylose content, water soluble polysaccharides, and starch content. A program of combining the wx and wxa alleles with certain of the tvelve genotypes has been undertaken with the hope of elucidating more fully, the sequence of gene action in determining amylose content in the endosperm.

 

Herbert H. Kramer

Gerald Dunn

Roy L. Whistler