Tables

<table><caption>**Table 1** Screening for presence or absence of myrosinase-like activity in bacteria and fungi isolated from a rapeseed soil using either selective or non-selective media amended or not with sinigrin (5 mM). Germination assays were conducted in 96-well plates in presence of GNT (5 10⁻⁶ M) with broomrape seeds as bioindicators for perception of glucosinolate-breakdown products.</caption><thead><tr><th>Kingdom</th><th>Taxonomic assignation <sup>a</sup></th><th>Strain name</th><th>Relative germination % <sup>b,c</sup></th><th>Medium</th></tr></thead><tbody><tr><td rowspan="10">Bacteria</td><td>Uncultured <i>Actinobacterium</i></td><td>Act_M9_1</td><td>96.68±1.86%</td><td rowspan="10">M9+Sinigrin</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_2</td><td>75.31±15.94%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_3</td><td>69.08±6.02%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_4</td><td>78.42±0.89%</td></tr><tr><td>Ralstonia <i>picketti</i></td><td>Ral_M9_5</td><td>90.12±8.73%</td></tr><tr><td>Uncultured <i>Proteobacterium</i></td><td>Prot_M9_6</td><td>74.72±5.98%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_7</td><td>67.94±2.18%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_8</td><td>94.68±11.93%</td></tr><tr><td><i>Chryseobacterium</i> sp.</td><td>Chry_M9_9</td><td>0%</td></tr><tr><td rowspan="10">Fungi</td><td><i>Penicillium</i> sp.</td><td>Pen_M9_1</td><td>46.32±26.00%</td><td rowspan="10">M9+Sinigrin</td></tr><tr><td><i>Penicillium echinalutum</i></td><td>Pen_M9_2</td><td>44.50±25.33%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_1</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_2</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_3</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_4</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_5</td><td>46.19±21.27%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_6</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_7</td><td>0%</td></tr><tr><td><i>Aspergillus ochraceus</i></td><td>Asp_PDA_1</td><td></td><td rowspan="4">PDA</td></tr><tr><td><i>Aspergillus</i> sp.</td><td>Asp_PDA_2</td><td>0%</td></tr><tr><td><i>Aspergillus versicolor</i></td><td>Asp_PDA_3</td><td></td></tr><tr><td><i>Aspergillus</i> sp.</td><td>Asp_PDA_4</td><td></td></tr></tbody></table>

<footnote><sup>a</sup> All strains were molecularly characterized using the V4 regions of 16S rRNA (16S) and internal transcribed spacer (ITS1) phylogenetic markers for bacteria and fungi respectively. Species was assigned when it belonged to the top hit, i.e. single species with identity percentage above 95%.</footnote>

<footnote><sup>b</sup> Percentages (mean±sd) are expressed as the number of germinated seeds on total seeds, relatively to the average ratio obtained with the positive control (rac-GR24 10⁻⁷ M).</footnote>

<footnote><sup>c</sup> Activity is validated and highlighted in red when relative germination is different than zero at the highest concentration of 0.01 OD₆₀₀ and 10⁻⁵ spores mL⁻¹ for bacteria and fungi respectively.</footnote>
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Tables

<table><caption>**Table 1** Screening for presence or absence of myrosinase-like activity in bacteria and fungi isolated from a rapeseed soil using either selective or non-selective media amended or not with sinigrin (5 mM). Germination assays were conducted in 96-well plates in presence of GNT (5 10⁻⁶ M) with broomrape seeds as bioindicators for perception of glucosinolate-breakdown products.</caption><thead><tr><th>Kingdom</th><th>Taxonomic assignation <sup>a</sup></th><th>Strain name</th><th>Relative germination % <sup>b,c</sup></th><th>Medium</th></tr></thead><tbody><tr><td rowspan="10">Bacteria</td><td>Uncultured <i>Actinobacterium</i></td><td>Act_M9_1</td><td>96.68±1.86%</td><td rowspan="10">M9+Sinigrin</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_2</td><td>75.31±15.94%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_3</td><td>69.08±6.02%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_4</td><td>78.42±0.89%</td></tr><tr><td>Ralstonia <i>picketti</i></td><td>Ral_M9_5</td><td>90.12±8.73%</td></tr><tr><td>Uncultured <i>Proteobacterium</i></td><td>Prot_M9_6</td><td>74.72±5.98%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_7</td><td>67.94±2.18%</td></tr><tr><td><i>Arthrobacter</i> sp.</td><td>Art_M9_8</td><td>94.68±11.93%</td></tr><tr><td><i>Chryseobacterium</i> sp.</td><td>Chry_M9_9</td><td>0%</td></tr><tr><td rowspan="10">Fungi</td><td><i>Penicillium</i> sp.</td><td>Pen_M9_1</td><td>46.32±26.00%</td><td rowspan="10">M9+Sinigrin</td></tr><tr><td><i>Penicillium echinalutum</i></td><td>Pen_M9_2</td><td>44.50±25.33%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_1</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_2</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_3</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_4</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_5</td><td>46.19±21.27%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_6</td><td>0%</td></tr><tr><td><i>Penicillium</i> sp.</td><td>Pen_PDB_7</td><td>0%</td></tr><tr><td><i>Aspergillus ochraceus</i></td><td>Asp_PDA_1</td><td></td><td rowspan="4">PDA</td></tr><tr><td><i>Aspergillus</i> sp.</td><td>Asp_PDA_2</td><td>0%</td></tr><tr><td><i>Aspergillus versicolor</i></td><td>Asp_PDA_3</td><td></td></tr><tr><td><i>Aspergillus</i> sp.</td><td>Asp_PDA_4</td><td></td></tr></tbody></table>

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<footnote><sup>a</sup> All strains were molecularly characterized using the V4 regions of 16S rRNA (16S) and internal transcribed spacer (ITS1) phylogenetic markers for bacteria and fungi respectively. Species was assigned when it belonged to the top hit, i.e. single species with identity percentage above 95%.</footnote>

<footnote><sup>b</sup> Percentages (mean±sd) are expressed as the number of germinated seeds on total seeds, relatively to the average ratio obtained with the positive control (rac-GR24 10⁻⁷ M).</footnote>

<footnote><sup>c</sup> Activity is validated and highlighted in red when relative germination is different than zero at the highest concentration of 0.01 OD₆₀₀ and 10⁻⁵ spores mL⁻¹ for bacteria and fungi respectively.</footnote>
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<figure><img src="image_1.png" /></figure>

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<caption>**Fig. 1** Relative abundance levels of bacterial families, expressed as mean percentages ± sd of all amplicon sequence variant (ASVs) detected in the rapeseed soil. DNA extraction was performed on three soil samples and amplification targeted the V4 region of the 16S rRNA genes. Taxonomic assignments were performed on the SILVA database. Taxa less than 0.1% abundant were grouped into the "< 0.1% abundant." class, and taxa with no family assignation of family level were grouped into the "NA" class (not available).</caption>
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<figure><img src="image_2.png" /></figure>

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**Fig.1** Relative abundance levels of bacterial families, expressed as mean percentages ± sd of all amplicon sequence variant (ASVs) detected in the rapeseed soil. DNA extraction was performed on three soil samples and amplification targeted the V4 region of the 16S rRNA genes. Taxonomic assignments were performed on the SILVA database. Taxa less than 0.1% abundant were grouped into the "< 0.1% abundant." class, and taxa with no family assignation of family level were grouped into the "NA" class (not available).
<figure><img src="image_2.png" /><figcaption>**Fig.2** Relative abundance levels of fungal families, expressed as mean percentages ± sd of all amplicon sequence variant (ASVs) detected in the rapeseed soil. DNA extraction was performed on three soil samples and amplification targeted the ITS region. Taxonomic assignations were performed on the UNITE database. Taxa less than 0.1% abundant were grouped into the "< 0.1% abond." class, and taxa with no family assignation of family level were grouped into the "NA" class (not available).</figcaption></figure>
<figure><img src="image_3.png" /><figcaption>**Fig.2** Relative abundance levels of fungal families, expressed as mean percentages ± sd of all amplicon sequence variant (ASVs) detected in the rapeseed soil. DNA extraction was performed on three soil samples and amplification targeted the ITS region. Taxonomic assignations were performed on the UNITE database. Taxa less than 0.1% abundant were grouped into the "< 0.1% abond." class, and taxa with no family assignation of family level were grouped into the "NA" class (not available).</figcaption></figure>
A

Week 1

<figure><img src="image_3.png" /></figure>

Week 2

<figure><img src="image_4.png" /></figure>

B

<figure><img src="image_5.png" /></figure>

Weeks after broomrape inoculation

Control Buffer 0.22µm filtered Unfiltered

C

<figure><img src="image_6.png" /></figure>
<figure><img src="image_4.png" /></figure>

<figure><img src="image_5.png" /></figure>

<figure><img src="image_6.png" /></figure>
**Fig.3A** Germination of broomrape seeds in mini-rhizotron systems, 1 and 2 weeks post broomrape inoculations on rapeseed roots. Percentages were calculated on 4 squares of 1cm². Different lowercase letters indicate significant differences of treatments (p-value <0.05) determined by ANOVA. **B** Successful broomrape attachment on rapeseed roots in mini-rhizotron systems, 2, 3 and 4 weeks post broomrape inoculation. Values are displayed as mean with standard deviation as error bars. Asterisks indicate significant differences 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘not significant (ns) ‘, compared to the control modality and determined by ANOVA on a Poisson distributed model. **C** Average proportion of the different broomrape developmental stages, reported as a relative ratio to the average number of total attached parasites. Stages correspond to Young (young tubercle without adventitious root), Spider (old tubercle bearing adventitious roots) and bud (bud with adventitious roots but without a stem). Different lowercase letters indicate significant differences of treatments (p-value <0.05) determined by ANOVA on logistic models for each stage. Bold and italic letters indicate comparisons between young and spiders respectively. No letter was displayed when there was no significant difference between modalities (i.e. Bud and Necrosis stages).

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**Fig.3A** Germination of broomrape seeds in mini-rhizotron systems, 1 and 2 weeks post broomrape inoculations on rapeseed roots. Percentages were calculated on 4 squares of 1cm². Different lowercase letters indicate significant differences of treatments (p-value <0.05) determined by ANOVA. **B** Successful broomrape attachment on rapeseed roots in mini-rhizotron systems, 2, 3 and 4 weeks post broomrape inoculation. Values are displayed as mean with standard deviation as error bars. Asterisks indicate significant differences 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘not significant (ns) ‘, compared to the control modality and determined by ANOVA on a Poisson distributed model. **C** Average proportion of the different broomrape developmental stages, reported as a relative ratio to the average number of total attached parasites. Stages correspond to Young (young tubercle without adventitious root), Spider (old tubercle bearing adventitious roots) and bud (bud with adventitious roots but without a stem). Different lowercase letters indicate significant differences of treatments (p-value <0.05) determined by ANOVA on logistic models for each stage. Bold and italic letters indicate comparisons between young and spiders respectively. No letter was displayed when there was no significant difference between modalities (i.e. Bud and Necrosis stages).

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<figure><img src="image_7.png" /></figure>

**Fig.4** Effect of soil extract and exogenous gluconasturtiin on broomrape germination. Germination of broomrape seeds after a four-day treatment in 96-well plates with unfiltered soil extracts at a 10-fold and 100-fold dilution with and without gluconasturtiin (GNT 10⁻⁶ M), or after co-treatment with GNT and treated soil extracts: 0.45 µm and 0.22 µm syringe filtration, addition of large spectral biocide (Plant-Preservative Mixture 0.1% v/v) with the unfiltered extract, and soil gamma-sterilization. Ratios are expressed as the number of germinated seeds on total seeds, relatively to the average ratio obtained with the positive control (racGR24 10⁻⁷ M, a synthetic strigolactone, maximum germination ratio = 1 ≈ 70.12±4.37% of germinated seeds). Different lowercase letters indicate significant differences (p-value <0.05), and determined by a Kruskal-Wallis rank sum test (non-normal data) and multiple pairwise comparison.
<figure><img src="image_7.png" /></figure>

**Fig.4** Effect of soil extract and exogenous gluconasturtiin on broomrape germination. Germination of broomrape seeds after a four-day treatment in 96-well plates with unfiltered soil extracts at a 10-fold and 100-fold dilution with and without gluconasturtiin (GNT 10⁻⁶ M), or after co-treatment with GNT and treated soil extracts: 0.45 µm and 0.22 µm syringe filtration, addition of large spectral biocide (Plant-Preservative Mixture 0.1% v/v) with the unfiltered extract, and soil gamma-sterilization. Ratios are expressed as the number of germinated seeds on total seeds, relatively to the average ratio obtained with the positive control (racGR24 10⁻⁷ M, a synthetic strigolactone, maximum germination ratio = 1 ≈ 70.12±4.37% of germinated seeds). Different lowercase letters indicate significant differences (p-value <0.05), and determined by a Kruskal-Wallis rank sum test (non-normal data) and multiple pairwise comparison.
<figure><img src="image_8.png" /><figcaption>**Fig.5A** Broomrape attachments to rapeseed roots in mini-rhizotrons, on day 7 to 21 post seed inoculation. Values are displayed as mean with standard deviation as error bars. Asterisks indicate significative p-values compared to the control modality 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ns’; determined by an ANOVA on a Poisson distributed model. **B** Corresponding tubercle developmental stages of the broomrape attachments to roots in mini-rhizotrons at day 21. Stages correspond to Young (young tubercle without adventitious root), Spider (old tubercle bearing adventitious roots) and bud (bud with adventitious roots but without a stem). Aggressiveness assays were conducted on germinated and 48 h pre-treated seeds with either control buffer solution, unfiltered soil extract or 0.22µm filtered soil extract or cytokinin (tZ 10⁻⁷ M). Differences of treatments (p-value <0.05) are determined by ANOVA on logistic models for each stage, but are not significant for any stage between modalities (ns).</figcaption></figure>
<figure><img src="image_8.png" /></figure>

**Fig.5A** Broomrape attachments to rapeseed roots in mini-rhizotrons, on day 7 to 21 post seed inoculation. Values are displayed as mean with standard deviation as error bars. Asterisks indicate significative p-values compared to the control modality 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ns’; determined by an ANOVA on a Poisson distributed model. **B** Corresponding tubercle developmental stages of the broomrape attachments to roots in mini-rhizotrons at day 21. Stages correspond to Young (young tubercle without adventitious root), Spider (old tubercle bearing adventitious roots) and bud (bud with adventitious roots but without a stem). Aggressiveness assays were conducted on germinated and 48 h pre-treated seeds with either control buffer solution, unfiltered soil extract or 0.22µm filtered soil extract or cytokinin (tZ 10⁻⁷ M). Differences of treatments (p-value <0.05) are determined by ANOVA on logistic models for each stage, but are not significant for any stage between modalities (ns).
<figure><img src="image_9.png" /><figcaption>**Fig. 6** Effect of soil extracts on prehaustorium formation in P. ramosa. Prehaustorium formed after a three-day treatment in 96-well plates with unfiltered soil extracts or treated soil extracts: 0.45 µm and 0.22 µm syringe filtration, addition of large spectral biocide (Plant-Preservative Mixture 0.1% v/v) with the unfiltered extract and soil gamma-sterilization. Ratios are expressed as the number of germinated seeds exhibiting prehaustoria (swollen radicles with papillae) on total germinated seeds, relatively to the average ratio obtained with the positive control (TDZ 10⁻⁸ M, a cytokinin-like molecule). Different lowercase letters indicate significant differences of treatments (p-value <0.05), determined by an ANOVA on a logistic model.</figcaption></figure>
<figure><img src="image_9.png" /><figcaption>**Fig. 6** Effect of soil extracts on prehaustorium formation in P. ramosa. Prehaustorium formed after a three-day treatment in 96-well plates with unfiltered soil extracts or treated soil extracts: 0.45 µm and 0.22 µm syringe filtration, addition of large spectral biocide (Plant-Preservative Mixture 0.1% v/v) with the unfiltered extract and soil gamma-sterilization. Ratios are expressed as the number of germinated seeds exhibiting prehaustoria (swollen radicles with papillae) on total germinated seeds, relatively to the average ratio obtained with the positive control (TDZ 10⁻⁸ M, a cytokinin-like molecule). Different lowercase letters indicate significant differences of treatments (p-value <0.05), determined by an ANOVA on a logistic model.</figcaption></figure>