JoeReal

The article below could be applied to banana seed germination:

"Seed the Day" by: Matthew Holm (Research/Penn State, Vol. 17, no.
1 (March, 1996))

On his porch, surrounded by plants and blooms from around the world,
Norm Deno tells me how, when he retired from his chemistry
professorship about 15 years ago, he went down to the library to see
what had been written about his lifelong hobby, seed germination. He
felt -- as he says, like Darwin at the Galapagos -- that everyone in
the field had somehow gotten it completely and utterly wrong. "My only
choice," he says, "was to do the whole field over.

"The problem all plants have, that most botanists have overlooked," he
says -- and he's tested more than 6000 species of plants -- "is
keeping the seeds from germinating." My first reaction is that this
energetic, eccentric, 70-something man has his statement backwards.

But then I look at his yard and see the ease with which the
wildflowers have devoured the land, staring lawn-care in the face and
laughing. Deno's yard is a testament to many things -- the beauty of
nature, the haziness between the terms weed and flower -- but
especially to the need for a plant to disperse its seeds. "You don't
want the seeds to start growing in the follicle," Norm says, and I can
see his point -- it would be rather embarrassing (if not fatal) for
seeds to germinate before they're off the branch. Plus, he adds, they
need to wait for the right growing conditions once they hit the
ground.

Deno's approach to seed germination -- the one that turns the field on
its head -- is that seeds have chemical inhibitors to prevent
germination. No seed can grow until these blocks have been destroyed
by things like temperature changes, moisture, and sunlight. These
conditions combine in nearly infinite ways, making each plant's
germination needs different. Of course, when you know what the proper
conditions are, you can break down the barriers relatively quickly and
easily -- this is why you can plant Burpee seeds straight from the
envelope (where they have waited in dry storage for several months)
and have sprouts in a few weeks, and why you can "force" a crocus to
bloom in February by keeping the bulb in your cool, dark garage and
then moving it to a sunlit windowsill.

To test his inhibitor theory and catalogue the germination patterns of
thousands of seeds, Deno employed some of the most powerful tools of
modern science: a small, brown, dormitory-style refrigerator, moist
paper towels, and polyethylene sandwich bags. His mighty home lab
sports a 6-foot long workbench, a row of unfinished plywood shelves,
some fluorescent lamps, and miscellaneous fly-fishing tackle -- a far
cry from the gas chromatographs, mass spectrometers, ultraviolet and
infrared lights of his chemistry days at Penn State, but it's all he
needed to redefine thought about seed germination.

In less than two years, his self-published, 242-page book (printed by
Kinko's Copy Center, no less), Seed Germination Theory and Practice,
has sold more than 8,000 copies without any advertising whatsoever --
Simon and Schuster, eat your heart out. Norm gets boxloads of mail
every day, from people asking him to try out some interesting seeds,
solve a tricky germination problem in South Africa, or send them his
book. "For $20, I'll get it to you anywhere in the world,
postage-paid," he grins.

Deno unashamedly acknowledges his success in the field, accrediting it
to good science. "One of the biggest mistakes experimenters made in
the past," says Deno, "was not controlling for the fungi in the soil,"
-- hence the moist paper towels and plastic bags, which make for a
sterile, controlled environment. The fungi are significant because
they, too, can break down the chemical inhibitors. Deno tells of a
cactus that will only germinate in the presence of a fungal chemical
called a gibberellin (gibberellins, of which only 3 of 70 known types
appear to affect plants, are not well understood). "Here you have this
tiny seed, with a tiny speck of a root, in the middle of this huge,
dry desert," he says -- if the seeds germinate just anywhere, they'll
surely die and the parent cactus will be left with no offspring. "What
it needs, then, is a pocket of moist leaf mold," says Deno. "It drifts
around and will only germinate when exposed to that gibberellin,
produced in that pocket of mold, where it can get a start."

This ingenious twist of natural selection demonstrates just one of the
six main ways that inhibitors are destroyed. Along with the
gibberellins go exposure to sunlight, dry storage (this works for most
seeds, including all of our grains), moist storage at 70 degrees F,
moist storage at 40 degrees F, and the puncturing of the seed coat.

This last method -- removing a physical rather than chemical block --
is the least common, used by only 5% of all species. But Deno, of
course, has some of these seeds as well -- he picks a Kentucky Coffee
Tree seed pod off the ground (his yard is littered with vegetation in
various states of growth and death, including a spectacular 150
different species in bloom -- just today) and tears it open, exposing
the smooth, dark, walnut-sized seeds that lie in a sticky, sickly
yellow paste.

"Raccoons carry these pods away, then eat the sweet stuff inside,"
Norm says, offering me a taste. I dab my fingertip in the goo, then
touch it to my tongue, where the initially sweet flavor soon fades
into a persistent sourness. As Norm warns, "Not too much -- I think
it's got toxins," I'm reminded of underripe banana.

As the raccoons take their treat home, they also disperse the seeds.
The seeds themselves, which look like they would require a few good
hours with a hammer and a tungsten-carbide drill to open, won't
germinate until heat expansion and contraction finally crack the shell
in another 5 to 10 years. "They can be viable for over 150 years,"
says Deno.

Dropping the seed and leaving it to its decades-long journey, he
ambles along the winding, rocky path through his sloping backyard.
Common and endangered plants vie for soil and sunlight in a manner
that would make a conservationist cringe. "I went to a Sierra Club
meeting," Deno says, shaking his head. "Once." At the meeting, he
recalls, the club members spoke for five minutes about the
disappearance of the lady slipper orchid, then spoke for 45 minutes
about the need to plant trees.

"Reforestation is the single worst thing for a lady slipper like the
Queen's lady slipper or the small white lady slipper," says Deno.
"Encroaching trees rob the orchids of the sunlight they require."
Under a large power line junction in Ohio, where every spring the
earth is intentionally burned free of brush and weeds, the white lady
slipper still covers acres. The snow orchis grows in the Bennett bogs
in New Jersey, Deno notes, because farmers mow the marsh in June,
allowing sun to reach the plant's ground-hugging rosettes. A rare
gentian in Centre County is found only along the roadside where the
road crews mow. "Many rare species of flowers exist only because of
man's interference," Deno says. "Without this, some of them would
probably be on their way out."

Deno's approach to conservation is realistic -- not everyone can be
responsible for saving all species simultaneously. He waves at a patch
of dry brown foliage where he has killed some flowers with Roundup,
saying, "My wife and I encourage a species to grow some years, then
cut it back other years." In his garden, everything gets its fair
turn. "If you want to preserve a species, then I think you need to set
aside an area and just concentrate on that one alone," he says. I am
reminded of the hundreds of thousands of seeds he has worked on and
the hundred or so more that await preparation later today as he tells
me, "You just have to take things one at a time."

Norman Deno, Ph.D., is professor emeritus of chemistry in the Eberly
College of Science, 139 Le Nor Dr., State College, PA 16801;
814-238-8770. Matthew Holm is a former writing intern at Research/Penn
State.