赤霉素对入侵植物凤眼莲营养生长和克隆繁殖的调控

The regulation of gibberellins on the vegetative growth and clonal propagation of the invasive plant Eichhornia crassipes

【目的】明确植物激素赤霉素对入侵植物凤眼莲营养生长和无性克隆繁殖的影响,探索凤眼莲快速生长繁殖的内在调控机理,为其科学防控及合理利用提供参考。【方法】在温室条件下用改良霍格兰营养液培养凤眼莲幼苗,并定期对其叶茎表面喷洒50μmol·L-1赤霉酸(GA 3),培养4周后检测其营养生长和无性繁殖指标,包括株高、根长、膨大茎周长、叶片的数量、叶片的长和宽、叶片叶绿素含量和氮含量、茎上组织重量、根重,以及克隆株数量和匍匐茎长度。【结果】相比于喷洒无菌水的对照,50μmol·L-1 GA 3处理后的凤眼莲叶柄明显增长,株高更高,根系较短,膨大茎消失;叶片数量无显著差别,但叶片形状由肾圆形变为心形,叶片宽度变窄,长度基本无变化,总体叶面积变小;叶片所含叶绿素和氮含量更少,茎上组织和根系重量变轻,但根冠比无明显变化,且基本不产生克隆株。【结论】外源喷洒赤霉素可以改变凤眼莲的植株形态,并抑制凤眼莲的叶片发育,从而造成其生物量累积和克隆繁殖水平的降低。

【Aim】The effects of gibberellins(GAs)on the vegetative growth and clonal propagation of the invasive plant Eichhornia crassipes were studied to better understand these mechanisms for its control and utilization.【Method】E.crassipes plantlets were cultivated under greenhouse conditions using modified Hoagland solution for 4 weeks and were periodically sprayed with 50μmol·L-1 gibberellic acid(GA 3),followed by measurement of vegetative growth and clonal propagation parameters,including height,root length,perimeters of bulbous petioles,leaf numbers,width and length of leaves,chlorophyll and nitrogen contents in leaves,weight,root weight,ramet numbers,as well as the stolon length.【Result】Compared with control,of which plants were sprayed with sterilized water,the GA 3 treatment increased plant height,whilst some other parameters including root length,leaf width,leaf area,chlorophyll and nitrogen contents,weight,root weight were all significantly decreased.In addition,GA 3-treated plants presented heart-shaped leaves instead of typical kidney shape.The leaf numbers and leaf length showed little difference between treatments.Moreover,GA 3-treated E.crassipes barely produced ramets.【Conclusion】Exogenously applied GA 3 modified the morphology of E.crassipes and depressed its leaf development,and thereby suppressed its biomass accumulation and clonal propagation.