The March 27 edition of Nature, an internationally known magazine published in England, carried an article by a specialist from the Republic of China on a new way to cultivate the oriental herb known as ginseng in vitro (from a test tube). In the article, Dr. Chang Wei-chin of the Institute of Botany of the Academia Sinica, explained how he had produced ginseng flowers with fertile pollen from germs taken from the root, without going through the long juvenile stage first.
Ginseng is regarded in the East as a tonic for a wide variety of ills. As the climate is too warm to raise the herb in Taiwan, it has to be imported at great expense, mainly from Korea. About two years ago, however, Dr. Chang and his research assistant Yueie Hsing started to experiment on the possibility of cultivating ginseng artificially from its cells (cloning).
A major breakthrough in plant science came when they discovered that the cultured callus (germ tissue) derived from ginseng can develop into embryoids, seedlings and flowers without going through a long juvenile phase. They followed this up by discovering a method to induce flowers directly from the embryoids, shortening the period needed to reach maturity from five years to only one or two months.
To achieve their goal, they first placed different types of ginseng tissue, including leaf, petiole, anthophore and stem in a test-tube culture, and added nutrition and hormone to encourage rapid growth of the callus. They continued to add hormones, and the embryoids started to produce flowers one or two months later.
The initial cell mass was called an embryoid rather than embryo, because it is asexually reproduced. Using natural methods, it takes 20 months for ginseng seeds to bud and grow leaves, and another three years to produce flowers.
Although experiments on similar lines have been carried out in many laboratories overseas, Dr. Chang is certainly the first researcher to induce flowers directly from embryoids without going through the juvenile stage. His article on the work was featured as a cover story by Nature magazine.
Dr. Chang's work will form a basis for researchers to find out whether his technique is applicable to other plants. If it is, it means that farmers will be able to cut down the time they have to wait for the result of a cross-pollination to bear flowers and fertile pollen.
Despite his success, Dr. Chang is not satisfied with his achievements so far. He is still trying to discover what roles nutrition and plant hormones play in enhancing the growth of the callus, embryoids and flowers of ginseng.
Dr. Chang, 40, a graduate of the horticulture department of the National Taiwan University, won his Ph.D. in plant physiology from the University of California, Riverside. In 1972, he ended his research work in the U.S. to return to settle down in his fatherland with his wife and two children. In addition to his work at the Academia Sinica, he lectures at his old department in the NTU.
"Although my salary may not be as high as it would be in the U.S., I am very satisfied with the excellent research environment in the Academia Sinica, and very pleased to contribute the results of my research to my country," said Dr. Chang.
Among projects he has worked out for the future are continued research into artificial cultivation of ginseng from its cells, and the shortening of the juvenile phase of orange and other crops. He also hopes that as a result of his work, the name of the Republic of China will appear more often in international scientific periodicals.
[Picture Caption]
Left: ginseng root; and right: Dr. Chang Wei-chin at work.
Top: Different types of ginseng tissue grow into calluses with the addition of nutrition and hormone. Right: Dr. Chang's research showed that the cultured callus derived from ginseng can develop into embryoids, seedlings and flowers without going through a long juvenile phase.
Left: Dr. Chang's second breakthrough was to discover a method to induce flowers directly from the embryoids. Right: Nature magazine uses Dr. Chang's article as its cover story. Below: Dr. and Mrs. Chang tend their garden during their spare time.
Dr. Chang Wei-chin at work.
Different types of ginseng tissue grow into calluses with the addition of nutrition and hormone.
Different types of ginseng tissue grow into calluses with the addition of nutrition and hormone.
Dr. Chang's research showed that the cultured callus derived from ginseng can develop into embryoids, seedlings and flowers without going through a long juvenile phase.
Dr. Chang's second breakthrough was to discover a method to induce flowers directly from the embryoids.
Nature magazine uses Dr. Chang's article as its cover story.
Dr. and Mrs. Chang tend their garden during their spare time.
