Scientists revive 32,000-year-old plant right out of the pleistocene
According to the Old Farmer’s Almanac, seeds available today are best grown when only a year old. Some will still germinate after 3 or 4 years, but after that, results are poor. How are seeds then preserved from year to year? They must be regrown and the new seeds collected. (1)
So, imagine the great surprise when in 2005 researchers from Israel successfully grew date palms… from 2000-year-old seeds recovered from an ancient fortress in the Middle East. These seeds were radiocarbon dated to be from the first century, thus the oldest seeds ever to sprout. This finding beat the previous well-documented record holder by about 700 years. It was a lotus found in a dry lake bed in China. This phenomenon was even entered into the Guinness Book of Records. (2)
Oldest Seeds Found
Incredibly, a team of Russian scientists has successfully grown a plant identified as Silene stenophylla from 32,000-year-old seeds. These seeds were found in squirrel burrows about 115 feet below the permafrost in Siberia. This area, formed about 60,000 years ago, is known as the Late Pleistocene ice complex found throughout the eastern Arctic which also includes Alaska and the Yukon where other frozen seeds have been found. (3)
Permafrost covers about 20 percent of the earth’s surface, the most widespread natural subzero depository now under extensive scientific investigation. Scientists believe this search for an ancient genetic pool will shed light on preexisting life which has long since vanished from the earth’s surface.
The Siberian research team worked in an area with layers of permafrost containing plant remnants and bones of large mammals like the mammoth, woolly rhinoceros, bison, and other specimens. The annual ground temperature is −7°C. Where the burrows were found, the temperature was estimated to have been at least −80°C, the minimum for cryopreservation to have occurred. (3)
A total of 70 fossil burrows were found. Incredibly, the number of seeds and fruits found in some chambers reaches up to 600–800 thousand. Fossils contained numerous substances including pollen, insects, plants, and mammal material. The plant material was radiocarbon dated. The material from the burrows is providing important evidence of rapid freezing and subsequent preservation without defrosting. (3)
Laboratory Results
Under strict laboratory conditions, the Russian researchers used tissue culture techniques to initially germinate the seeds of Silene stenophylla retrieved from the Siberian site. Once germinated, the seeds were placed in sterile potting soil and left to grow. Since Silene stenophylla is a perennial, it flowered the second year. The plant was then identified by Moscow State University. (3)
The discovery and subsequent research on ancient seeds is an important scientific challenge. Cryopreservation indicates that long-term conservation of viable biological material is possible. Seed banks like Svalbard Global Seed Vault in Norway which now houses 1,059,646 unique crop varieties are hoping to add some of these 32,000-year-old seeds to their inventory. Future research may help improve modern varieties for better yields and resistance to pests without the use of chemicals. This would be a great contribution to the environment and marginalized people in countries with challenging growing conditions and starvation issues. (4)