EULISS, KATY W.* and JEFFREY S. CARMICHAEL. Biology Department, University of North Dakota, Grand Forks, ND, 58202. - The effects of selenium accumulation in canola (Brassica napus).
Trace amounts of selenium are considered essential for proper growth
and development in most organisms. However, high levels of selenium
can cause adverse effects in animals as well as most plants. Canola
(Brassica napus) has been studied for its potential use in
phytoremediation of seleniferous soil because of its ability to
accumulate relatively high levels of this potentially toxic element.
While much is known about the role of selenium in higher plants and
the use of plants for phytoremediation, relatively little is known
about the effects of selenium on developmental events and the impacts
of selenium on reproductive success (e.g., seed set). Studies
presented here reveal intriguing and unexpected results. We found that
canola plants grown hydroponically in 2 ppm selenium displayed
significantly reduced flowering and seed set. In particular, we found
that compared to controls, selenium treatment resulted in fewer plants
flowering and an overall lower seed yield. Comparable numbers of seeds
per pod were produced in selenium-treated and control plants, but seed
viability was reduced in selenium-treated plants. Plant height and
leaf production were also negatively impacted by selenium. The effects
of selenium on vegetative anatomy along with herbivore and pathogen
defense will be discussed.
Key words: Brassica napus, canola, herbivore, selenium