∫Biology dz/dt

Venus Kuo, IBH Senior, collecting soil samples on Barro Colorado Island, Panama

SUMMER RESEARCH 2014

This summer I'm glad to report we have two IB Honors students doing independent research at the Smithsonian Tropical Research Institute (STRI) in Panama.

Nathan Stables, IBH junior, is part of the NSF funded  STRI REU Program which matches student research interests with those of faculty mentors that do research based in Panama. Nathan is working with Prof. Andy Jones measuring genome sizes of tropical trees along sites that differ in soil fertility.

Venus Kuo, IBH senior, is working with me! Venus is part of a larger NSF funded project that is exploring how seeds are defended against diverse predators and pathogens, and how defensive traits are linked more broadly to tree life history. Venus was recently featured in STRI's weekly newsletter (photo and text courtesy of Sean Mattson).

"The hot and humid tropical forest floor voraciously decomposes

virtually anything that is biodegradable. So it came as a
bit of a surprise when Jim Dalling, a professor at the University
of Illinois, demonstrated that seeds from some pioneer tree species
can retain their ability to germinate for up to four decades
in forest topsoil.
His research, published in The American Naturalist in 2009,
inspired Venus Kuo, an undergrad at UI, to find out what keeps
seeds viable. She suspects soil fungi. “Do they play some kind of
a protective, mutually beneficial role for the seeds?” asked Kuo,
as she hiked to the 50-hectare forest plot on Panama’s Barro
Colorado Island where the seeds for the original study
were collected.
Pioneer trees are the first to emerge when a forest regenerates.
But they need a lot of light and this is in low supply in the
understory. Not until a tree falls and opens a gap will pioneers
have a chance to grow into reproductive adults.
Kuo will collect seeds from Dalling’s sites as well as other spots
in the 50-hectare plot where tree census data suggest pioneer
species rained seeds on the forest floor decades ago. She will
test the seeds for viability and diversity of endophytic fungi, and
compare her findings with younger seeds. She expects fungal
diversity will be lower in older seeds, pointing to which fungi
may promote long-term seed dormancy.
“I think it can probably lead to some interesting questions
about how we can predict tree emergence and canopy composition
over time,” said Kuo".