9604460 Phinney The overall research goal of this laboratory is to understand the biochemical, genetic and molecular basis for gibberellin (GA)-dependent shoot growth in maize. The program is important to the advancement of science in that the results define control elements for the growth of maize, an important economic plant for the welfare of society. Gibberellins are plant hormones that are controllers of shoot growth. They are present throughout the plant kingdom. The Principal Investigator (PI) has pioneered the use of single gene mutants to unravel the details of the GA-biosynthetic pathway; these mutants have also been used to evaluate the biological significance of specific gibberellins in their control of growth. The projected program will continue studies on the gibberellins of maize which will (i) define the biosynthetic origin and metabolism of specific maize gibberellins, (ii) locate specific steps in the pathway that are blocked by dwarf mutants (GA-mutants) and (iii) screen for transposon tagged GA-dwarf mutants with a goal of cloning and expressing the genes that control steps in the maize biosynthetic pathway. This project addresses the biological routes for synthesis of gibberellins, plant hormones that regulate shoot growth. The way gibberellins are made in corn will be studied using combination of chemical and genetic experimental approaches. The work is important because it will lead to a greater understanding of how plant growth is controlled. This work has both basic and practical importance and may eventually lead to increased crop productivity and an increase in the world's food supplies.
