空心莲子草无性繁殖体片段引入频率对其萌芽及幼苗生长的影响

摘要

[Objective]The study aimed to discuss the effect of introduced frequency of vegetative propagation fragments in A. phioxeroides on the establishment of its population, and provided the basis for deeply understanding the invasion mechanisms of A. phioxeroides and controlling its spread. [Method]In summer of 2006, the subterranean stem fragments and fleshy root fragments of A. phioxeroides were implanted with different Introduced frequencies in the plastic pots with soil, after covering soil by 2 cm, the total fragments of fleshy root or subterranean stem in each pot were 15, and the experiments were repeated by 7 times. After fishing the implantation on last subterranean stem fragments or fleshy root they were germinated and grew for 1 month and the budding was stabilized and the new seeds were produced no longer. At this time all the A. phioxeroides were harvested to determine the sprout number, the branch node number as well as the total biomass of each pot. [Result]At introduction for 1 time, the sprout number per pot for the vegetative propagation fragments (subterranean stem and fleshy root) in A. phioxeroides was less than that of introductions for several times (P＜0.05, n=7), but there was no significant difference on the sprout number in introductions for several times as 3 times, 5 times and 15 times (P＞0.05, n=7). The introduction for 1 time and introductions for several times had no significant effect (P＞0.05, n=7) on the branch node number and biomass of A. phioxeroides. [Conclusion]The introductions by several times for vegetative propagation fragments were favorable to ensure the sprout number of A. phioxeroides, which increased the invasive risk. Even at introduction for 1 time, as long as there were a certain number of unearthed sprouts, a good clonal population of A. phioxeroides could be established after a period of growth.%[目的]探讨空心莲子草无性繁殖体片段引入频率对其种群建立的影响,为深入理解空心莲子草入侵机制和控制其蔓延提供基础.[方法]在2006年夏季,将空心莲子草地下茎片段和肉质根片段以不同引入频率埋植在带土塑料盆中,覆土2 cm,每盆中的地下茎或者肉质根片段总数为15根,重复7次.最后一个地下茎片段或者肉质根片段埋植完成后,经过一个月的萌芽及生长,萌芽趋于稳定,不再产生新的萌芽,此时全部收获空心莲子草,测定每盆的萌芽数、分枝茎节数、总生物量.[结果]1次引入条件下,空心莲子草无性繁殖体(地下茎和肉质根)片段的每盆总萌芽数显著低于多次引入(P＜0.05,n=7),多次引入(3次、5次、15次)之间萌芽数差异不显著(P＞0.05,n=7);1次引入和多次引入对空心莲子草的分枝茎节数、生物量均没有显著影响(P＞0.05,n=7).[结论]空心莲子草无性繁殖体的多次引入对于保证空心莲子草的萌芽数有利,但增加了入侵的风险;即使是1次引入,只要有一定数量的萌芽出土,经过一段时间生长后,空心莲子草也能建立良好的无性系种群.