My program presently centers on two sets of developmental mutants of pea with altered stem elongation and photoperiod response. The major genes controlling plant stature regulate biosynthesis of, and plant response to, gibberellins. We have been studying the effects of these genes on gibberellin metabolism and stem elongation.
Efforts are underway to clone genes involved in gibberellin biosynthesis.
By isolating these genes, we hope to determine their relationship to specific tissues and organs, and stage of development, as well as the effects of light, photoperiod and other environmental factors. The major genes controlling flowering and photoperiod response comprise a classic system for the study of juvenility and photoperiod. In pea, hormones clearly mediate the effects of photoperiod on plant growth. Gibberellins play a role in photoperiodic control of internode elongation, but their effects on apical growth and development, including flowering, is less clear. We have identified gibberellins in pea associated with photoperiod and the photoperiod genes.