Lewis Knudson ( 1884 - 1958 )

Prior to Federal quarantine regulations which prohibited the importation of orchid plants into the United States , large numbers were collected and there was a constant supply of plants and bloom for a flourshing industry . The Department of Agriculture's quarantine regulations sharply curtailed this seemingly unlimited supply of plants ,however. In addition , growers were desirous of producing hybrids which would give flowers of higher quality and which would permit flower production throughout the year instead of during relatively short seasons .The problem of successfully germinating orchid seed was a limiting factor , though . Noel Bernad had shown in 1909 that orchid seeds in nature required mycorrhizal fungi for germination , and out of this work a method was developed whereby a culture medium could be used and the fungus artificially introduced . A certain degree of success was attained for a young plant physiologist at Cornell University , Ithaca ,New York , to become interested in the problem and to develop the asymbiotic method of orchid seed germination that revolutionized the commercial orchid industry . This man was Lewis Knudson.

Lews Knudson was born in Milwaukee , wisconsin , oN 15 October 1884 . After graduating from the University of Missouri in 1908 with the degree of B.S.A , he went to Cornell University as assistant in plant physiology and began teaching graduate students , all of whom were older than he. Liberty Hyde Bailey , then dean of the College of Agriculture , had told the head of the plant physiology department that he might engage an assistant who would be willing to do considerable rough work in addition to other duties ,and who could be discharged at the end of the spring term if it seemed advisable . By the end of the term Knudson had been advanced to instructor status , however , receiving his doctorate and becoming assistant professor of plant physiology in 1911! His first major research was on tannic acid fermentation , and one of his two Ph.D. theses was written on that subject. Shortly afterward ,he and his graduate students developed one of the first reliable cultures of nitrogen-fixing bacteria for inoculation of legumes.

Upon the resignation of Professor B.M. Duggar, whom Knudson had worked under , in 1912 he was made acting head of the Department of Plant Physiology ,which in 1916 he was made acting head of the Department of Botany ,and so Knudson gained another title: professor of botany .

One of Knudson's main interests was the organic nutrition of plants . In 1916 he began growing various plants in environments free from microorganisms. As a result of his investigations on the use of sugar by plants and his development of pure culture , in 1917 he adapted his techniques to the germination of orchid seeds .

In 1919 he was invited by the Spanish government to establish the study of plant physiology in Spain and to give courses in Madrid and Barcelona .Six months were spent in Spain and a year in France,, where be carried out research at the Sorbonne and attended lectures in the Pasteur Institute . Here he was able t o attend Madame Marie Curie's discussions on radium.

Continued interest in the pure culture growth of plants and his interest in the theories of Noel Bernad in France and Hans Burgeff in Germany led him to the hypothesis that orchid seeds could be germinated without the presence of the mycoorhizal fungi but with sugars and starches. European botanists were aroused to caustic comment by Knudson's early papers on these ideas.The hypothesis was verified when put to test , however. Eight years of investigation and experiments in seed germination enabled knudson to prove conclusively that orchid seed could be successfully germinated on an artificial culture medium . This breakthrough brought about a revolution and a new awakening in orchid hybridization on both the amateur and commercial levels . Eventually Knudson published over twenty papers on the subject.

In 1938 the vanilla industry in Puerto Rico was threatened by a disease that caused continued root decompositiion . A request for aid was sent to Cornell and Knudson responded . The solution appeared to be the development of hybrids resistant to root decay and of equal or better quality than that of Vanilla fragrans , then being cultivated for its flavoring . Knudson's experimentation in pollination and asymbiotic seed germination led to the development of two rot-resistant hybrids-the first Vanilla hybrids produced.

In 1941 Professor Knudson became head of the Department of Botany at Cornell .For twelve years he was consultant for the United Fruit Company and organized much of the research on bananas both in the tropics and in the United States , and his interest in the problems of tropical agriculture took him on many trips to the countries of Central America. His work there became a major contribution to the economy of those conuntries . His investigations dealt with a very distructive disease of bananas , with culture methods of producing bananas , and with the physiology of ripening of the fruit . The research involved resulted in better selection of farming land, increased productivity per acre, and the abandonment of replanting and cultivation by disc and harrow.

Less widely known but nevertheless noteworthy was his interest in the effects of radiation on chloroplast morphology in ferns .The pure culture technique was also used in this study, and through the use of X-ray on fern spores ,many extraordinary permanent mutations were induced .

Knudson was an exceptionally effective teacher in both elementary and advanced courses of plant physiology and , when necessary , also lectured with marked success in the general botany courses . By his sympathetic and stimulatind direction , twenty-five students completed the work necessary for the doctor's degree under him. Many of these students became widely known in plant physiology , horticulture ,and related sciences.

During his period of active service Lewis Knudson was appointed to many of the most important committees of Cornell University , and memberships and honors were granted him other organizations. He had been vice-president of the American Orchid Society , which in 1949 conferred on him its Gold Medal for distinguished service to orchiology. He was also an honorary member of the Orchid Societies of Caracas, Venezuela , and of Brazil; a fellow of the American Association for the Advancement of Science ; a member of the Botanical Society of America ; honorary member of the Real Sociedad Espanola de Historia Natural; and member of the American Society of Naturalists, American Society of Plant Physiologists ,Alpha Zeta , Gamma Alpha , Sigma Xi, and Phi Kappa Phi.

Knudson retired , after forty-five years of service to Cornell , on 30 June 1952. Even after retirement , however , his interests in science and plant physiology remained strong, and his emeritus activities in consultation and research continued without pause.

To honor him , the Federated Garden Clubs of New York State presented him its Gold Medal award in 1956 " for distinguished service in scientific research on the physiology and nutrition of plants ," an honor conferred on only one other scientist , the famed Liberty Hyde Bailey . In 1957 he was awarded the degree of honorary doctor of science by hi s alma matuer , the University of Missouri .

On 31 August 1958 ,at seventy -three years of age , he died in his home at Ithaca ,New York . He had practically completed a monograph of the banana at the time of his death . He was survived by his widow ,Caroline I .Knudson , and two sons.

References

American Orchid Society Bulletin . 1958 .Necrology .Vol. 27,no.10.

American Orchid Society Bulletin . 1950. Society Honors Two Scientists .Vol. 19 ,no. 8.

Nature . 1958. Vol. 182,p. 1640.

Miscellaneous papers provided by Cornell University, Ithaca , New York.