黄香草木犀水浸提液对杂草种子萌发和幼苗生长的影响

Aqueous Extraction of Melilotus officinalis on Seed Germinationand Seedling Growth of Weeds

通过种子萌发和幼苗生长试验,探讨黄香草木犀水浸提液对其自身及4种常见杂草生长发育的影响。结果表明,黄香草木犀水浸提液对其自身和其他杂草都存在明显的化感作用,但其化感作用强度则取决于受体植物种类及浸提液的浓度。种子萌发试验表明,黄香草木犀水浸提液降低其自身和狗尾草的发芽率,而提高马齿苋和牛筋草的发芽率,且均在高浓度时效果显著(p<0.05);但对反枝苋却有“低抑高促”作用。除了牛筋草在高浓度(3.3%~10.0%)时发芽势有所增加以外,黄香草木犀水浸提液明显降低其自身、狗尾草、反枝苋和马齿苋的发芽势,且随着浓度增加而抑制作用显著。幼苗生长试验表明,黄香草木犀水浸提液增加了2种双子叶植物的株高(p<0.05);对2种单子叶植物及其自身则为“低抑高促”作用。狗尾草、牛筋草和反枝苋的地上生物量随浸提液浓度的增加而增加(p<0.05);对于马齿苋为高浓度促进、低浓度抑制的影响,这和对黄香草木犀自身植株的生长和生物量积累的情况完全相反。地下生物量的结果则表明,黄香草木犀对2种单子叶杂草均为促进作用,而对2种双子叶杂草则为“低抑高促”的作用,而对其自身根系的生长则表现为明显的抑制作用,且浓度越高抑制作用越明显。

Through seed germination and seedling growth experiment,aqueous extraction of Melilotus officinalis was used to test the effects of allelopathy on seedling growth and development of its own and four other weeds.The results showed that there was clear allelopathic effect of Melilotus officinalis on itself and other weeds,but its efficacy depended on species and the concentration of extraction.According to the seed germination experiment,it showed that the aqueous extraction of Melilotus officinalis reduced the germination rate of itself and green bristle grass(Setaria viridis),while it was promoted for purslane(Portulaca oleracea)and Indian goose grass(Eleusine indica).What’s more,the inhibition or promotion effect was significant at high concentration(p<0.05).The germination rate of common amaranth(Amaranthus retroflexus)significantly increased at higher concentration,but presenting an inhibition at a lower concentration.Germination potential decreased significantly with the refined extraction for Melilotus officinalis itself,green bristle grass,common amaranth,and purslane except for Indian goose grass at a high concentration(3.3%-10.0%).In terms of plant height,it obviously promoted the growth of purslane and common amaranth as dicotyledon plants(p<0.05)with the increased concentration;while for monocotyledonous plants like green bristle grass and Indian goose grass,even for Melilotus officinalis itself,plant height was inhibited at low concentration but promoted at high concentration.For biomass,the aboveground biomass was accumulated with the increased concentration of extraction for green bristle grass,common amaranth,and Indian goose grass(p<0.05),but presenting an inhibition effect to purslane at low concentration and promoting effects at high concentration which was opposite to Melilotus officinalis.The determination of the underground biomass of the weeds showed that it was promoted by the extraction for the monocotyledons,while the effect of inhibition for lower concentration and promotion for higher concentration was presented for the two dicotyledonous weeds.Anyhow,for Melilotus officinalis,the higher the concentration was,the more obvious the inhibition effect was.