入侵植物黄顶菊与3种牧草竞争效应研究

Competitive Effects between Invasive Plant Flaveria bidentis and Three Pasture Species

以入侵植物黄顶菊和多年生黑麦草、紫花苜蓿、高丹草3种牧草为试验材料,采用盆栽取代试验方法观察了不同密度及比例条件下4种植物的竞争表现,为黄顶菊生物替代提供理论依据.结果表明:(1)在3种牧草中,高丹草对黄顶菊株高控制效果最为明显,并以苗期效果最好,在低密度比例下对黄顶菊抑制率即可达60.00%;而多年生黑麦草和紫花苜蓿的控制效果较差,在低密度比例下对黄顶菊起不到抑制作用.(2)在高丹草低密度替代组合中,黄顶菊单株生物量、分枝数比对照均明显减少,抑制率分别可达91.40%和44.87%;而多年生黑麦草和紫花苜蓿各密度替代组合中,黄顶菊单株生物量、分枝数与对照相同或大于对照.(3)在各个生育时期,除高密度高丹草替代组合外,其他组合中黄顶菊的相对产量值均极显著小于1.0,生长受明显抑制;而在各替代密度下,多年生黑麦草、紫花苜蓿与黄顶菊竞争替代效果均不明显.研究发现,高丹草的替代效果明显优于多年生黑麦草和紫花苜蓿,可以作为生物替代的材料对黄顶菊进行替代控制,且在植株比为1∶3比例下即可实现理想控制效果.

In present study,a greenhouse competition experiment was conducted with invasive plant Flaveria bidentis and three pasture species,Lolium perenne,Medicago sativa and Sorghum bicolor×Sorghum sudanense,with different densities and proportions combination,to investigate their competitive behavior.The results as follow：（1）Among the three pasture species studied,the most inhibitory effect on F.bidentis height was observed with S.bicolor×S.sudanense,especially at seedling stage,and F.bidentis height was reduced by 40% even with lowest density and proportion;there are no inhibitory effect on F.bidentis height was observed with Lolium perenne and Medicago sativa in lowest density and proportion.（2）In low-density replacement combination with S.bicolor×S.sudanense,the plant biomass and number of branches of F.bidentis were reduced to 91.40%,44.87%,compared with the control（P0.05）.However,in low-density replacement combination with L.perenne and M.sativa,the plant biomass and number of branches of F.bidentis were equal or even bigger than that of contron.（3）The RY value of F.bidentis plants,when growing with S.bicolor×S.sudanense,was significantly less than 1.0 with obvious growth inhibition observed at both low and intermediate densities through the whole season.However,both L.perenne and M.sativa had little inhibitory effect on F.bidentis plants irrespective of the densities employed.To summery,the present study suggests that S.bicolor×S.sudanense was preference choice,thus it could be used as biological alternative material to manage F.bidentis invasion.Also,an ideal control might be achieved using a proportion of 1∶3（S.bicolor×S.sudanense：F.bidentis）.