FIGURE LEGENDS
FIGURE 1 Inhibition of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars on weed number and biomass (all species pooled) in a paddy field. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Values were calculated as percentages relative to controls (plots without rice). Columns with different letters indicate significant differences within each cultivar at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
FIGURE 2 Inhibition of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars on four paddy weeds and their barnyardgrass-based mixtures. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Values were calculated as percentages relative to controls (weeds only). Columns with different letters indicate significant differences within the same weeds and their mixtures at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
FIGURE 3 Root intrusion of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars in the present of paddy weeds. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’and’Lingyou-3826’ (both indica) and Liaojing (japonica). Control, allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ monocultures in the absence of paddy weeds. Vn/Va values indicate root placement patterns of unresponsive (Vn/Va=1), intrusive (Vn/Va > 1), or avoidance (Vn/Va <1).
FIGURE 4 Root avoidance of paddy weeds in response to allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Control, paddy weeds monocultures without any rice cultivars. Vn/Va values indicate root placement patterns of unresponsive (Vn/Va=1), intrusive (Vn/Va > 1), or avoidance (Vn/Va <1).
FIGURE 5 Production of allelochemicals (tricin and momilactone B) from allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars in presence of barnyardgrass and barnyardgrass-based weed mixtures. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Values were calculated as percent increase above controls (no weeds). Columns with different letters indicate significant differences within barnyardgrass or its mixtures with other weeds at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
FIGURE 6 Plots of principal components analysis of PLFA composition in the soils grown by focal rice cultivar ‘Huagan-3’, ‘Lingyou-6173’ or barnyardgrass monocultures and their mixed-cultures. Data used in PCA plots were transformed using sample unit totals to represent the relative abundance of each PLFA (mole percentage of total PLFA).
FIGURE 7 Inhibition of barnyardgrass by allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars under applied NH4NO3 and allantoin. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Values were calculated as % reduction relative to controls (no rice). Columns with different letters indicate significant differences at P < 0.05 among different related cultivar in the same nitrogen treatment according to ANOVA, followed by Turkey HSD tests.
FIGURE 8 Root/shoot carbon and nitrogen ratios of barnyardgrass in the presence of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars under applied NH4NO3 and allantoin. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Control, barnyardgrass monocultures.
Supplementary Figure 1 Pot experiments for the performance of weeds by allelopathic rice cultivars mixed with different related cultivars at seedling stage. Control refers weed monocultures. Only barnyardgrass is shown here.
Supplementary Figure 2 Rhizobox experiments for the root placement pattern of weeds in the presence of allelopathic rice cultivars mixed with different related cultivars at seedling stage. Top panel illustrates the planting design in an individual rhizobox. Control refers to weed monoculture. Only barnyardgrass is shown here.
Supplementary Figure 3 Distribution of root length and biomass of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars in the presence of paddy weeds. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Columns with different letters indicate significant differences within each weed at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
Supplementary Figure 4 Distribution of root length and biomass of paddy weeds in response to allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’and’Lingyou-3826’ (both indica) and Liaojing (japonica). Columns with different letters indicate significant differences within each weed at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
Supplementary Figure 5 Inhibition of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars on barnyardgrass and barnyardgrass-based weed mixtures at rice mature stage. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Values were calculated as percentages relative to controls (weeds only). Columns with different letters indicate significant differences within barnyardgras or its mixtures with other weeds at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
Supplementary Figure 6 Grain biomass of allelopathic rice cultivars ‘Huagan-3’ and ‘Lingyou-6173’ mixed with different related cultivars in presence of barnyardgrass and barnyardgrass-based weed mixtures. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars ‘Huafeng’ and ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Columns with different letters indicate significant differences within barnyardgras or its mixtures with other weeds at P < 0.05 according to ANOVA, followed by Turkey HSD tests.
Supplementary Figure 7 Relative abundance of bacterial, fungal, actinobacterial PLFAs in the soils grown by focal rice cultivar ‘Huagan-3’, ‘Lingyou-6173’ or barnyardgrass monocultures and their mixed-cultures. Closely related cultivars, ‘Huagan-8’ and ‘Lingyou-6365’. Distantly related cultivars, ‘Huafeng’, ‘Lingyou-3826’ (both indica) and Liaojing (japonica). Columns with different letters indicate significant differences within the same PLFA at P< 0.05 according to ANOVA, followed by Turkey HSD tests.