During my earlier years, I investigated the mechanism of action of the hormone auxin and several synthetic plant growth regulators/herbicides. This led us into the study of chromosomal proteins, those proteins associated with DNA, because they were believed to regulate gene expression. Among other things, we found evidence that the histones did not play the specific regulatory role or perform some other functions they were believed to. During the late 1960s, we began to study whole plant (monocarpic) senescence, and in 1974, this became my primary research interest. Most of our early work dealt with monocarpic senescence in soybean, but later, we shifted to Arabidopsis. We began with examination of the correlative controls and used this information to study the hormonal controls, particularly cytokinin. We have also worked on several mutations that alter senescence. We used the information on correlative, hormonal and gene controls as tools to probe the biochemistry of monocarpic senescence. Because monocarpic senescence is tied to the repoductive structures in these plants and because of the yield implications, we also investigated the development of the reproductive structures.
Depending on progress with the plant longevity book, I plan to resume (hopefully in 2010) some limited teaching with a freshman seminar. This seminar course probably would deal with herbal medicines and nutrients, but it would emphasize the underlying science including the natural adaptive values of these plant constituents. Although this would be an outgrowth of my plant constituents course, it would also be a change in direction for me.
Eventually, I hope to resume some experimental projects dealing with plant senescence.I am also engaged in a variety of conservation projects.
Telephone: +1 (734) 764-4436 Fax: +1 (734) 763-0544 OR +1 (734) 647-0884 E-mail: ldnum@umich.edu
This page last updated: 11 Jan 2009