Generation of the genetic mutant population for the screening and characterization of the mutants in response to drought in maize

The autonomous Mutator ( Mu ) transposon in maize ( Zea mays L.) lines 115F, 330I, and 715D were crossed with inbred lines B73, Mo17, 97108, and H9-21, M 1 were self-pollinated to establish the Mu insertion-mutagenized M 2 seeds pool and The M 2 plants encompassed a large amount of biological variation relevant to improving agronomy traits by observed in the field. Next we statistically analyzed these candidate mutants. Under drought stress, we screened seedlings at 3-leaf stage by using the infrared thermography, and successfully got 108 drought-insensitive and 121 drought-sensitive candidate mutants from more than 38,000 lines, which temperature were significant different with others. These candidate mutants were primarily analyzed by infrared thermography, chlorophyll fluorescence, leaf water losing, photosynthetic characteristics, content of soluble sugars, soluble protein, and proline assay. The selected mutants were cloned by MuTAIL–PCR methods. Here we provide the better genetic materials for research on maize breeding for drought tolerance.