One of the World’s Longest-Running Experiments Sends Up Sprouts

David Lowry was impatient for the very old seeds to wake up. For days, Dr. Lowry, an assistant professor of botany at Michigan State University, had entered a basement room at the school, peeked into the growth chamber and seen only dirt.

But on April 23, he checked again and there it was: A tiny plant, its two leaves reaching upward. “It was kind of an amazing moment,” he said.

This was no average springtime sprout. Back in 1879, the botanist William James Beal plucked that seed and thousands of others from different weedy plants in and around East Lansing, Mich. He then stashed them in bottles and buried them in a secret spot on the Michigan State campus, with the goal of learning whether they’d still grow after years, decades or even centuries of dormancy. In mid-April, Dr. Lowry and four colleagues sneaked out under cover of night to dig one of the bottles up and plant its contents, thus continuing one of the longest-running experiments in the world.

Through late April and early May, more seedlings peeked above the soil — 11 as of Tuesday. One is a bit of a mystery, with leaves that are hairier and sharper-edged than those of the other sprouts.

The rest are most likely Verbascum blattaria, a tall, jaunty-flowered herb that has emerged as the experiment’s undisputed champ. Commonly known as moth mullein for its antenna-like stamens, this species was introduced to North America in the 1800s and lives an unassuming life in fields and meadows.

This plant’s victory is lucky, because it probably wasn’t supposed to be part of the experiment. Apparently Dr. Beal had intended to preserve a different species, Verbascum thapsus. That one was present in the first eight bottles and fared less well, with few of its seeds growing after only 20 years of dormancy.

V. blattaria first showed up in the ninth bottle, sneaking in through what was perhaps a case of mistaken identity by Dr. Beal. Since then it has been quite successful — out of the 50 V. blattaria seeds originally placed in each bottle, 31 germinated after 50 years, followed by 34 after 60 years, and so on. In 2000, when the previous bottle was dug up and tested, nearly half of the V. blattaria seeds grew sucessfully.

It will take time for the team to definitively determine exactly what has sprouted, and to conclude that the other seeds aren’t viable. In the coming weeks, they will give all the bottle’s seeds additional cues that could spur them to sprout: a cold treatment, a smoke bath and a spray with a plant growth hormone. (In 2000, a cold treatment led to the germination of a single Malva pusilla seed, the only non-Verbascum plant to come up that year.)

They may also may make small cuts on some of the larger seeds. “Rough them up on the outside, because that causes germination for some,” said Marjorie Weber, a team member and an assistant professor of plant biology at the university.

While it’s hard to draw many conclusions at this stage, the fact that any plants grew at all after such a long dormancy is “amazing,” Dr. Lowry said.

Margaret Fleming, a postdoctoral researcher and a member of the team, said that the seeds’ eagerness to germinate demonstrates their health. “Some of them are just chugging along like no time has passed,” she said.

The apparent persistence of V. blattaria — a weedy, nonnative species — also has implications for conservation. If species like this can survive underground for decades or even centuries, they may pop up on land that people are attempting to turn into native plant habitat — “presenting surprises and maybe even challenges to restoration projects long into the future,” said Lars Brudvig, another team member and an associate professor of plant ecology at the university.

Now that the latest seed bottle has been successfully harvested, the team is eager to sew new ones. While this experiment isn’t set to end until the year 2100, “the time is now” to start preparing a follow-up, said Frank Telewski, a professor of plant biology at the university and the longest-standing member of the Beal experiment team.

The core of the experiment will remain the same — seeds, bottles, time — but there are a few things this group aims to do differently, to protect their successors from the confusion and temptation they currently face.

They will check how many seeds from each species germinate when planted right away — something Dr. Beal did not do when he buried the bottles in 1879. That has left the current team without a baseline for comparison of long-term tests.

They also plan to bury twice as many bottles, leaving one for planting, and one to explore whatever “the coolest question” happens to be when it’s dug up — even if that requires destroying the seeds, Dr. Brudvig said. And stringent protocols for seed identification will also help them ensure they don’t mix up species like Dr. Beal did.

They may even say goodbye to the secret spot: The “actual, long-term ecological research sites” that have been established since Dr. Beal’s time may be safer places to stash an important experiment, Dr. Lowry said.

As they solidify their plans, they are also building a seed recruitment list. While the new experiment, like the original, will have some invasive, weedy plants, it will also include native plants and some that are known to have unusual germination cues, like smoke and cold.

And Verbascum blattaria will be tapped again, “of course,” Dr. Telewski said. The team might even include some seeds from this year’s sprouts — which, after their time in the growth chamber, may be given a spot in the university’s W.J. Beal Botanical Garden. There, after over 140 years underground, these patient plants could finally feel the sun.

Source: Read Full Article