关键词: 杉木, 林木育种, 林木改良, 采穗圃, 无性系选择

Abstract: A hedged orchard for cutting production of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook. ) occupying 0.80ha. Has been established since 1986. 31, 000 seedlings originated from desired provenances, families and seed orchards were planted in the orchard as donors. The orchard is unique to the existing ones found in the literature due to the fact that no main stems can be seen, while shoots come up from the stems lying underground and are also collected from the cuttings underground. Experiments showed that the number of the cuttings produced in 1m~2 of the orchard area was about 270 in the second year and 470 in the third year of the establishment. This means that the number of the rooted cuttings yielded in a given hedged orchard area is double or even triple the number of the seedlings produced in the same area of a seed orchard at the highest yielding age of 10 years.An average of 90% rooting survival rate in practice was obtained with no shading, no irrigation and no hormone treatment. No damping-off disease was found. Both average height and diameter at the root collar were larger in the rooted cuttings than in the seedlings of the same age. About 230 000 rooted cuttings, whose expected genetic gain would be equal to that of the original stocks were produced in the past two years, and 600 000 propagules are now growing in the nursery beds. The cost of a rooted cutting was 20% lower than that of a seedling.The techniques for cstablishing a hedged orchard, and the efforts to obtain high yields of shoots and to reduce the cost are also recommended in this paper.

Key words: Cunninghamia lanceolata (Lamb.) Hook, Forest tree breeding, Forest tree improvement, Hedged orchard, Clonal selection