Abstract:

Since 1982, the experiments of the rare-earth application to forestry have been carried out with both pot-planted seedlings and field trees. The results proved that the rare-earth can increase the seed germination rate, and growth of forest trees at nursery stock stage, and improve the quality of nursery stockes, e. g. Cunninghamia lanceolata (Lamb.) Hook, Schima superba Gardn, et champ, Castanea mollissima Blume, Paulownia sp., Populus sp.etc. It can also raise the seed yields and quality of Pinus elliottii Engelm and Cunninghamia lanceolata in a seed orchard. And there are obvious effects on the fruit set percentage and yields, as well as improving the quality of fruits for some dry or fresh fruit tree species, such as Juglant regia L., Ziayphus jujuba Mill, Castanea mollissima, Maius pumila Mill, Pyrus bretschmeideri Rehd, Crataegus pinnstifida Bge, Diospyros kaki L., Prunus armeniaca L., and so on. The studies on physiological effects of it in forest tree species during its nursery stock stage, and in economic forest tree species during its flowering and fruiting period indicate that it can promot chlorophyll formation and mineral element absorption by roots, increase photosynthetic intensity and dry matter accumulation, as well influence the contents of some organic acids, protein, fat, sugar, and Vc etc in the fruits and seeds. Now the technique for the rare-earth application to forestry have been used in production practice as a result of studing it for many years.

Key words: Rare-earth, Nursery stock, Economic forest tree, Quality of mursery stock, Quality of fruit, Physiological effect