Ginseng, one of mankind’s oldest panaceas, and cloning, one of science's more recent discoveries, have been brought together by a Taiwan scientist in what may become a major breakthrough in crossbreeding techniques. The British scientific journal Nature featured the breakthrough in a cover story, and the prestigious German Theoretical and Applied Genetics also gave the story prominent coverage. Numerous European and American scientists have since arrived to observe the research firsthand. Among the many visitors has been Nobel Prize winner, Dr. John Kendrew.
The man behind all this commotion in scientific circles is an unassuming and jean-clad botanist, Dr. Chang Wei-chin, who, since 1972 has been quietly experimenting in his laboratory at Taiwan's Academia Sinica, the highest research center on the island.
"My earliest experiments were not with ginseng,” the 40-year-old scientist explained. “A friend gave me a ginseng root sample two years ago and, purely out of curiosity, I included it in the lab experiments. Ginseng always has fascinated the Chinese as a panacea for various human ills and, interestingly enough, a considerable amount of evidence has been found to support some of the traditional Chinese theories. I was told that even the Russian astronauts took some ginseng with them when they journeyed to outer space.”
For three years previous, Dr. Chang had been producing clones in vitro (in test tubes) from various tissue selections of a wide variety of medicinal plants. His hope had been to discover a way to shorten the length of time usually needed by a plant to mature and bear pollen. If such a shortcut could be found, he felt, then hopefully it could be applied to commercial crops such as citrus, pear and apple trees, cutting their juvenile period before flowering from many years to just a few months. The results would not only have far-reaching scientific implications, but be a boon to commercial crop raising - something highly significant for hungry Third World countries.
Test tube life and cloning have become popular of late as themes of science-fiction novels and movies where Frankenstein-like monsters are created by mad scientists. But actually, the whole idea of cloning began, Dr. Chang informed me, over 150 years ago, At that time, two European botanists, Schleiden and Schwann, came up with a theory that each separate cell of plant had within it all the blueprints for reproduction. It was not until many years later, however, that the theory was proven to be factual when biologists propagated plants, using individual cells taken from a parent. This type of asexual reproduction was shown to have both advantages and disadvantages in that the clone is genetically identical with the parent. On the positive side, this means that superior hybrids with high productivity and the best resistance can be mass produced without any variation. On the other hand, if climatic conditions or other factors change, a cloned plant is not able to meet the new conditions.
It is not with cloning, nor even with ginseng, however, that Dr. Chang made his historic finding, but with altering the growth cycle of plants.
"Under normal field conditions," Dr. Chang commented, "it usually takes a plant like ginseng five years to flower. For citrus and other commercial plants, the time is even longer. My work has been in using synthetic plant hormones to induce flowering without the plant first having to go through a lengthy juvenile stage.
Left, a rack of test tubes; right, the culture.
"For seven years," he continued, "I have been conducting experiments with all sorts of plants and hormones, producing clones from tissue sections called callus."
A callus, Dr. Chang explained, was basically an unorganized mass of cells, much like scar tissue produced on a cut finger. The plant callus was produced in a test tube by placing a cutting or piece of the plant in a nutrient and agar culture. The agar was added, he pointed out, to prevent the callus from sinking to the bottom of the test tube and thereby drowning. When various combinations of hormones were added to this culture, all sorts of fascinating results took place. It was precisely through such experimentation that Dr. Chang sped up the growth process of ginseng.
"After including ginseng in my experimentation for more than a year, and not having any results, I was about to drop it. Appendages could be grown from the ginseng callus, but I had no other results. Then, by luck, one combination of hormones suddenly activated the callus to not only produce a clone, but one that miraculously bypassed most of the juvenile stage and began to produce embryoids (asexually produced embryos), seedlings and even flowers."
The advances of science are based on careful, painstaking, repetitive work, precisely observed and controlled.
Dr. Chang's breakthrough was followed by his manipulating another hormone change where he induced embryoids to produce flowers directly and skip the seedling stage.
"My work is only the beginning," he cautioned, "for my lab experiments do not alter the time needed for a ginseng plant to produce commercially valuable ginseng roots. It is only the time required for lab cultures to bear flowers which has so far been shortened. We feel it's a good start, though, in that the test tube pollen is fertile. If the process can be imitated with other plants, this will cut the time usually needed by plant breeders to wait for their plants to bear flowers and fertile pollen."
Assisting Dr, Chang in his experimentations al Academia Sinica is a staff of relatively young lab technicians and associates.
"Even our senior botany staff is young," he smiled, "the average age being around forty."
Several of his lab technicians are overseas Chinese who heard about what he was doing and came to investigate and help. Dr. Chang himself would like to spend a sabbatical overseas to observe similar research in other experimental centers. As it is, his doctorate is from the University of California al Riverside, and he did post-doctorate work at Utah State University.
In 1980, Dr. Chang delivered a paper on his ginseng research at the Third International Ginseng Symposium in Seoul, Korea.
Cloning – Science fiction comes true.
"I am impressed with the amount of scientific interest in ginseng," he observed, "But don't get me wrong. It's no superstar, not yet proven to be anyway."
Dr. Chang doesn’t consider himself a particularly religious man, yet he feels very much a part of China's ancient Taoist tradition of scientific experimentation and investigation. Taoist alchemists may not have discovered their much sought after philosophers' stones or elixirs but, as Dr. Chang points out, they did establish in the process a scientific tradition in China which led to the invention of gunpowder, the compass and the development of dyes, porcelains, alloys and a host of medical insights and herbal cures. It was Taoist alchemy, in fact, which in many ways was the precursor of modern pharmacology, chemistry and astronomy.
It is in keeping with this venerable Chinese scientific tradition that Dr. Chang and his associates and colleagues at Academia Sinica are continuing their experiments. And, it seems altogether fitting that their research should include a plant long believed by Taoist medicine to offer great benefit to mankind… ginseng, an ancient panacea that just may become a model for modern science as well.