日本落叶松、杂种落叶松嫩枝全光喷雾扦插的研究

利用日本落叶松优树子代2.5年生的幼树、50.5年生优树及9.5年生杂种落叶松优良个体做为采条母树,以河沙、锯末、蛭石为基质,借用长臂旋转扫描喷雾装置,在全光喷雾条件下,扦插半木质化的嫩枝获得成功。2.5年生幼树条扦插生根率达95％以上(6月20日扦插),17个9.5年生杂种落叶松优株条扦插(7月20日),平均生根率,河沙基质为74.31％,锯末基质为68.60％,蛭石基质为51.90％,生根率最高的系达到96.20％,生根率超过70％以上的系占41.18％。扦插基质对生根的影响作用,以河沙为最好。50.5年生的成龄母树条扦插,幼化的干萌条和嫁接后的幼树条扦插,都比没有经过幼化处理的插穗提高生根率。生根素IBA、ABT处理2.5年生幼树条,7月20日扦插,对生根速度有作用,生根素浓度,50ppm比100ppm好,处理50.5年生成龄母树条100ppm比50ppm好。

STUDY ON TWIG CUTTING OF JAPANESE LARCH AND LARCH HYBRIDS UNDER CONDITION OF SPRAYING IN FULL LIGHT

By means of the progeny of Japanese larch tree, 2.5 years old seedings, and 50.5 years old plus tree as well as 9.5 years old fine individuals of larch hybrids as mother tree of cuttings succeses have been chalked from placing the twig before the new growth becomes hardened as cuttings in a rooting medium, such as sand, sawdust and vermiculite under the condition of spraying in the full light. The rooting rate has reached more than 95 per cent of 2.5 years old seedlings that were placed in June 20, while that of the cuttings from seventeen lines of 9.5 years old fine individuals of larch hybrids that were placed in July 20 are 74.31, 68.60 and 51.90 per cent in sand, sawdusts and vermicucu lite rooting medium respectively, in which the lines with more than 70 per cent in the rooting rate is 41.18 per cent and 98.20 per cent in rooting rate is the highest one. The rooting medium has an effect on the rooting,in general, which is proved best in sand. The cuttings from 50.5 old mother trees in mature age, dry cuttings through the treatment of returning to the juvinile easy to root and the twigs of young trees from grating have higher rooting rate than that of no treatment. Rooting hormones (principally IBA and ABT) are usually beneficial, in creasing the speed of rooting when to treat the cuttings of 2.5 years old seedling placed in July 20.50ppm of the hormones concentration are better than 100ppm of that for twigs of 2.5 years old seedling, on the contrary for 50.5 years old mother trees in mature age.