Table S1 Information on Allelopathy of the Nine Studied Invasive Plant Species

Table S1 Information on allelopathy of the nine studied invasive plant species

Invasive plants Release pathway Allelopathic effect References

Ageratina adenophora Water and organic extracts of Inhibiting seed germination and growth of Pisum sativum, [1-3]

leaves, stems, and roots Oryza sativa, Rumex acetosa and so on

Ageratum conyzoides Essential oil Inhibiting seed germination and growth of Arachis hypogaen, [4-6]

Cucumis sativus, Triticum aestivum, and Lolium perenne

Bidens pilosa Water extracts of stems, leaves, Inhibiting seed germination and growth of Amaranthus [7-10]

and roots viridis, Medicago sativa, Oxalis corniculata,

Toona sinensis and so on

Chromolaena odorata Essential oil; water extracts of Inhibiting seed germination and growth of Raphanus sativus, [11-13]

stems and leaves; leaf leachate Capsicum frutescens, Cucumis sativus and so on

Gynura crepidioides Water extracts of stems and Inhibiting seed germination and growth of Triticum aestivum [14]

leaves and Zea mays

Lantana camara Essential oil; water extracts of Inhibiting seed germination and growth of Oryza sativas, [15-18]

stems, roots, and leaves, Amaranthus hybrius, Alectryon subcinereu,

rhizosphere soils Cryptocara rigida and so on

Mikania micrantha Essential oil; organic extracts of Inhibiting seed germination and growth of Cucumis sativus [19-21]

stems and leaves and Oryza sativa, and rice blast

Tihonia diversifolia Water extracts of stems and Inhibiting seed germination and growth of Oryza sativa and [22, 23]

leaves Vigna radiate, and spore germination of Pteris vittata

Wedelia trilobata Water extracts of stems and Inhibiting seed germination and growth of Brassica [24-28]

Leaves; root exudates and parachtnensis, Oryza sativa, Arachis hypogaen,

volatile Echinochloa crusgalli and so on

Table S2 Characteristics of the soils from three sites invaded by Ageratina adenophora for different time

Soil Source pH A.N A.P A.K Organic matter Soil microbial biomass C

mg kg-1 mg kg--1 mg kg--1 g kg-1 μg g-1 (mean ± se)

Soil from site invaded long 5.36 367 26.97 67 5.32 341.16.60 ± 30.80

Soil from site invaded intermediately 4.61 333 1.77 140 4.11 369.60 ± 20.67

Soil from site invaded shortly 5.34 142 2.67 131 2.34 280.80 ± 19.70

A.N, A.P, and A.K indicate available N, P, and K, respectively. The differences in soil microbial biomass are not significant among the soils.

Table S3 Effects of soil sources (SS; n = 3), soil sterilization treatments (SST; n = 2), and their interaction on response index (RI) of Oryza sativa to leaf leachate of Ageratina odenophora according to a two-way ANOVA

Variables RI based on shoot length RI based on root length

Df F-value P-value Df F-value P-value

SS 2 5.883 0.006 2 30.056 <0.001

SST 1 380.975 <0.001 1 463.808 <0.001

SS × SST 2 0.023 0.977 2 5.398 0.008

Error 42 42

Table S4 Effect of soil sterilization treatment (SST; n =2), soil sources (SS; n = 3), degradation time (T; n = 6) in soils, and their interaction on contents of 9-Oxo -10,11 -dehydroageraphorone (DTD) and 9β-Hydroxyageraphorone (HHO) according to a three-way ANOVA

Variables DTD content HHO content

Df F-value P-value Df F-value P-value

SST 1 5029.510 <0.001 1 892.571 <0.001

SS 2 40.808 <0.001 2 14.533 <0.001

T 5 377.856 <0.001 5 75.949 <0.001

SST × SS 2 105.077 <0.001 2 19.388 <0.001

SST × T 5 188.388 <0.001 5 55.449 <0.001

SS × T 10 9.451 <0.001 10 9.908 <0.001

SST × SS × T 10 17.793 <0.001 10 10.394 <0.001

Error 72 72

Fig. S1 Response index of upland rice to leaf leachates of Ageratina adenophora (a, b), Chromolaena odorata (c, d), Lantana camara (e, f), Wedelia trilobata (g, h), and Tihonia diversifolia (i, j) in substrates with 0, 10, 30, 50, 70, and 100% of the soil sample from corresponding species (mixed evenly with the sterilized soil deep below ground). Values of R2 and P are from non-linear regressions (y= y0 + axb) for all panels except panel E.

References

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