青葙的自毒作用及对其他植物的化感作用

Autotoxicity of Celosia argentea and its allelopathic effects on other plants

【目的】研究青葙Celosia argentea L.的自毒作用及对其他植物的化感作用,从化感作用的角度探讨其作为常见田间杂草并与入侵植物三叶鬼针草Bidens pilosa L.共存的适应机制。【方法】采用室内生测方法,测定了青葙新鲜叶片水浸提液对青葙、三叶鬼针草、油菜Brassica campestris L.和萝卜Raphanus sativus L.4种植物种子萌发和幼苗生长的影响;采用室内盆栽试验,测定了青葙鲜叶水提取液浇灌和鲜叶覆盖对青葙生长的影响,以及青葙和三叶鬼针草凋落物覆盖的相互化感作用。【结果】青葙鲜叶水浸提液对4种受体植物种子萌发和幼苗生长均有不同程度的抑制作用,且随着提取液质量浓度的增加,抑制作用增强。无论是浇灌青葙水浸提液还是添加青葙叶片覆盖的处理都可以降低盆栽青葙的生物量,其中,质量浓度为0.250 0 g·mL^(-1)提取液浇灌盆栽的青葙,其生物量比对照降低了37.5%。将三叶鬼针草和青葙的凋落物覆盖盆栽的青葙和三叶鬼针草,40 d后均显著抑制了青葙生物量;与对照相比,单独覆盖青葙凋落物使盆栽三叶鬼针草的地上部质量和总生物量分别降低了23.0%和22.2%。【结论】青葙既有自毒作用,又对油菜和萝卜有较强的化感作用,应控制田间青葙的大量生长,同时栽培青葙时应避免连作;青葙和三叶鬼针草具有相互的化感抑制作用,青葙通过化感作用实现与三叶鬼针草的共存。

【Objective】To demonstrate the autotoxicity and allelopathic potentials of Celosia argentea L.against other plants,discuss the adaptive mechanism of C.argentea as a common field weed and co-existence with the invasive plant Bidens pilosa.【Method】Laboratory bioassay was used to evaluate allelopathic potentials of aqueous leachate of C.argentea fresh leaves on seed germination and seedling growth of four different plants,including C.argentea,B.pilosa,Brassica campestris and Raphanus sativus.Meanwhile,pot experiments were conducted to determine the effects of aqueous leachate and litter mulching of C.argentea fresh leaves on itself growth,and mutual allelopathic potentials of C.argentea and B.pilosa litter.【Result】The aqueous leachate of C.argentea leaves displayed varying inhibitory effects on seed germination and seedling growth of four tested plants,and this inhibition increased with increasing concentrations.The aqueous leachate of C.argentea leaves at 0.2 500 g·mL^–1 reduced itself root biomass by 37.5%.Litter mulching of C.argentea and B.pilosa significantly reduced the biomass of C.argentea after 40 days.Compared with the control,root biomass and total biomass of B.pilosa seedlings treated with litter mulching of B.pilosa decreased by 23.0%and 22.2%respectively.【Conclusion】Not only C.argentea plant has autotoxicity,but also it has strong allelopathic effects on B.campestris and R.sativus.The large amount of C.argentea growth in field should be controlled,and monoculture and continuous cropping of C.argentea should be avoided.The mutual allelopathic inhibition was found between C.argentea and B.pilosa plants,and the co-existence of C.argentea with B.pilosa was conducted with the allelopathic effect.