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