Fig. 1

Outline of the construction of the EMS-induced mutant library. Seeds were treated with a chemical mutagen (0.35 % EMS). To increase the mutation density, bulk M2 seeds from approximately 2000 M1 plants were treated again with 0.35 % EMS and 8000 M2 seeds used to grow M1’ plants; the generation after the second mutagen treatment was called M1’ to discriminate it from the initial M1 generation. M2' seeds were collected each from 1762 M1' plants. A total of 1762 M2' plants were grown and used to extract DNA. Twenty-six potential out-crossing plants were removed, resulting in a total of 1736 M2’ plants. The resultant library consisted of DNA derived from 1536 M2’ plants; 1437 of which produced seeds. Seeds from each line were stored with their corresponding DNAs