Survival curves for earthworm departures.

<p>Results of survival curve analysis for the departure of the first (a) and second (b) earthworms from groups of 1, 2, 5 or 10 earthworms; t₀ for the second earthworm is the departure time of the first.</p

Mean proportion of earthworms leaving a cluster over 60, 120 and 180 min.

<p>as a function of the initial size of the cluster. * denotes threshold for 60, 120 and 180 min.</p

Time equation of the first earthworm's departure.

<p>Average time to departure is a function of the cluster size and its adjustment (black line).</p

Earthworms clusters.

<p>(a) Earthworm group in a rearing box; (b) self-assembled earthworm cluster formed out of the soil.</p

Results of joining assays in the circular arena: total number of isolated earthworms reaching the central region or the edge for each cluster size; and average times to the first movement and to arrival at the central region.

<p>Results of joining assays in the circular arena: total number of isolated earthworms reaching the central region or the edge for each cluster size; and average times to the first movement and to arrival at the central region.</p

Y binary choice and arena set-ups.

<p>(a) Y device. A = 2.5 cm long neutral area where a single earthworm is placed at the beginning of the experiments, B = two lateral branches (2, 2.5 or 3 cm long), C = Circle chambers (3.5 cm diam.) where 15, or 0, earthworms were placed during the experiments; (b) Lateral and frontal view of the circular glass arena (20 cm diam.) with concentric circles (drawn on a transparent sheet affixed below) and indicating the central region (a circle of 4 cm diam.) the glass arena was elevated by a pedestal (10 cm).</p

Thresholds of the aggregate.

<p>(a) Distribution of cluster size at 5 hours for three different initial populations: 2 earthworms, 5 earthworms, and 9 earthworms, with the probability of joining μ = 0.02 min⁻¹ and that of leaving Q(N) = N^−2.6/6.25 min⁻¹. (b) Mean cluster size at 5 hours as a function of the initial size with the probability of joining (μ) = 0.02 min⁻¹ and that of leaving Q(N) = N^−2.6/6.25 min⁻¹.</p

Additional file 1: Figure S1. of Influence of rhizobacterial volatiles on the root system architecture and the production and allocation of biomass in the model grass Brachypodium distachyon (L.) P. Beauv.

Impact of individual strain volatile compounds on Total Secondary Root Length (A), Total Adventitious Root Length (B) and Secondary Root Density (C). The strains are grouped according to the clusters defined earlier, based on PC. Within each cluster, the strains are ranked in ascending mean value order. Presented values are means of the four experimental replicates (64 or 128 biological replicates +/− confidence interval (α = 5 %) for each strain and the control, respectively). Significant changes compared with the control without bacteria are marked with an asterisk (*). (DOCX 374 kb