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Although some germination may occur with or without
stratification methods, seed reproduction from these
cultivated trees has been nearly impossible. From
1980-1983, John E. Kuser of Rutgers University and
Donald Hendricks of the Dawes Arboretum determined
that inbreeding depression of pollen and cones was the
cause of this problem. It was known that the original
stock was from the Suisapa Valley and none from
outside that area, but it was also believed that the
seed might have originated from a single tree. DNA
testing has proven this not to be true; however, they
are from seed stock derived from no more than two or
three individual trees and collected during the
1946-1947 expeditions. These two men initiated a
program of seed collecting from across the entire
native range of trees in China. Seed from more than 50
trees were collected in 1990-1991 and sent to Arnold
Arboretum by Professor Minghe of Huazhong Agricultural
University. Later, the new stock of seeds and
seedlings were shared with arboretums throughout the
world, and made available to the public, thus
providing much of the genetic diversity of the extant
tree in China to the cultivated stock.
Dieses Phänomen wird durch Margits Anzuchterfolg im Grunde genommen in Frage gerstellt. Man müsste aber die Originalliteratur lesen um zu wissen was genau der Herr Kuser denn mit "Depression" mein- nur daß die Samen der ersten Generation nicht gut keimten ? Oder auch eine verkümmerte Wuchsform ? Oder gar bloß ein Peak in irgendeinem Diagramm einer Genanalyse der vielleicht gar nicht so eindeutig interpretierbar ist ?
In Frage kommen:
[] Kuser, John E. 1998-1999. Metasequoia
glyptostroboides: Fifty Years of Growth in North
America. Arnoldia 58(4) and 59(1): 76-79.
[] Kuser, John E. 1983, July. Inbreeding depression in
Metasequoia. Journal of the Arnold Arboretum 64, July.
[] Kuser, John E. 1982. Metasequoia Keeps On Growing.
Arnoldia, Journal of the Arnold Arboretum 42(3), pp.
130-138.
[] Kuser, John E. Assistant Professor Department of
Horticulture and Forestry, Cooke College New Jersey
Agricultural Experiment Station, Rutgers University
New Brunswick, New Jersey. 1983. Metasequoia
glyptostroboides In Urban Forestry. In Metria 4,
Proceedings of the fourth conference of the
Metropolitan Tree Improvement Alliance, New York
Botanical Garden, June 20-21. Pp. 20-27.
[] Kuser, J.E. 1981. Redwoods around the world. American
Forests 87(2): 30-32, 60.
[] Hendricks, Donald R., Director, Dawes Arboretum,
Newark, Ohio. 1995, Summer. Metasequoia Depression,
Sex, and Other Useful Information. Landscape Plant
News, University of Minnesota Landscape Arboretum,
V.6, #2. One of the early reports on reproduction of
Metasequoia from newly introduced seed after 1991.