Grönroos Roland, Flygh Gunnar, Kähr Monika, VON Arnold Sara
Department of Forest Genetics, Uppsala Genetic Center, Swedish University of Agricultural Sciences, Box 7027, S-750 07 Uppsala, Sweden.
Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences, Box 7072, S-750 07 Uppsala, Sweden.
New Phytol. 1993 Dec;125(4):829-836. doi: 10.1111/j.1469-8137.1993.tb03931.x.
Three different types of rooted hypocotyl cuttings showed relative growth rates close to those recorded as maximal for seedlings of Pinus contorta Dougl. ex Loud. However, slight differences in growth rate were noted depending on how the cuttings had been rooted. (I) Cuttings rooted in vitro initially formed a large wound tissue at the base from which roots subsequently developed. (II) Cuttings rooted ex vitro formed roots without previous formation of a wound tissue at the root-shoot connection. I and II produced plants with in average two roots per plant and the plants grew at similar relative growth rates (6.86 and 6.88 % per day respectively). (III) Auxin-rooted cuttings also formed roots (21 per plant) without previous formation of a wound tissue and had a slightly higher growth rate (7.65 % d ). The growth rate of auxin-rooted cuttings was not significantly different from the 8.67 % d obtained in seedlings. The conclusions drawn from these experiments were that; (1) rooted cuttings have the capacity to grow almost as fast as seedlings, (2) wound tissue produced prior to rooting or an extended period before the roots develop does not have a negative affect on the growth capacity of the cuttings, (3) the number of roots per cutting did not affect growth rate.
三种不同类型的带根下胚轴插条的相对生长速率，接近扭叶松（Pinus contorta Dougl. ex Loud.）幼苗所记录的最大生长速率。然而，根据插条生根的方式不同，生长速率存在细微差异。（I）在体外生根的插条最初在基部形成大量创伤组织，随后从该组织上长出根。（II）在体外生根的插条在根茎连接处没有预先形成创伤组织就长出了根。I和II类型的插条平均每株植物有两条根，植株以相似的相对生长速率生长（分别为每天6.86%和6.88%）。（III）用生长素处理生根的插条也在没有预先形成创伤组织的情况下长出了根（每株21条），并且生长速率略高（每天7.65%）。用生长素处理生根的插条的生长速率与幼苗所获得的每天8.67%没有显著差异。从这些实验得出的结论是：（1）带根插条的生长速度几乎与幼苗一样快，（2）生根前产生的创伤组织或在根发育前的一段较长时间，对插条的生长能力没有负面影响，（3）每个插条的根数不影响生长速率。
