建立水曲柳无性系种子园几项技术的研究

TECHNOLOGY OF ESTABLISHING CLONAL SEED ORCHARDS OF MANDSHURIAN ASH

水曲柳(Fraxinus mandshurica Prpr.)是我国北方珍贵的用材树种之一。为探讨该树种培育优良品种的新途径,尽快实现良种化造林,于1976年开始选优规划、建立无性系种子园,面积为1.5 ha。1983年有73％的无性系开花结实,结实期比天然林提前24—26a,比人工林提前14—16a。1985—1987年开花结实的无性系由73％提高到91％,平均单株产量为190g,已造子代林0.5 ha。试验认定4月20日—5月19日为最佳嫁接时间,劈接法成活率最高,嫁接前接穗浸水,接后及时除掉砧木萌条对嫁接成活率提高极为有利。无性系配置采用雌无性系顺序系统排列,雄无性系隔行隔株随机排列,园内雌雄比为6:1,4:1,株行距5m×6 m为好。在管理上进行全面除草,可以促进结实,比对照提前4 a,生长期每年延长17.9 d。

Mandshurian ash is one of the most valuable species in China. In order to reforest with genetically improved seedlings, the selection of superior seeds and the establishment of a elonal seed orchard of mandshurian ash were made in 1976. The orchard, made up of two plots of 1.5 ha, 73％ Clones beared and flowered in 1983, 24—26 years earlier than natural forest and 14—16 years earlier than plantation, folwering and seed production increased to 91％ in 1985—1987. Mean individual tree yield is 190 g, 0.5 ha filial generation had been constructed. To increase grafting survival rate, April 20 to May 19 is the optimum time, the scion were soaked in water before grafting, survival and growth will be affected if the sprout is not cut for more than once in the year of grafting. The clones arranged as follows: Female clone was located orderly, and male clone was located randomly every lines and individuals. The ratio of female to male clones is 6:1 and 4:1, spacing 5m×6m. completely weeding during growing season to promote fruit, and fruit 4 years earlier than the control, growth period prolonged 17.9 days each year.