Fig 4. Stimulation of plant defense after ApHRC was
silenced.
Relative ApHRC expression in Serratia -infected (a) aphid
body and (b) salivary glands 24 h after injection of dsHRC -RNA
(n=6). (c-e) EPG results of dsGFP : Serratia -infected aphid
injected dsGFP as control, and dsHRC :ApHRC -silenced Serratia -infected aphid for 8 h on M.
truncatula. (c) Time spent on salivary secretion into sieve elements
(E1 wave) (n=10). (d) Ingestion time (E2 wave) (n=10). (e) Time of
intracellular punctures (pd wave) (n=10). (f-j) Relative expression ofM. truncatula JA and SA pathway genes induced by dsHRC-and dsGFP -aphids infestation. (f) PAL , phenylalanine
ammonia lyase; (g) NPR1 , nonexpresser of PR genes 1; (h)PR1 , pathogenesis-related protein 1; (i) LOX2 ,
lipoxygenase 2; (j) AOS2 , allene oxide synthase 2. (n=6). (k)
H2O2 concentration induced by 10
dsHRC and dsGFP aphids, respectively for 6h (n=6). (l)
Subcellular localization of fluorescent probes, DCFH-DA, in leaves ofM. truncatula infiltrate by dsGFP -aphid (the middle panel)
and dsHRC aphid saliva (the lower panel). Control (the upper
panel): 15% sucrose solution treatment. Bars = 100 μm. (m) Normalized
fluorescence (ΔF/F0) of Ca2+ signal
measurements every 3 s in N. benthamiana detached leaves
infiltrated by dsGFP -aphid and dsHRC -aphid saliva.
Control: 15% sucrose solution treatment. ΔF, the difference between
measured fluorescence and the fluorescence of the very first picture
(F0) (n=15). Yellow shading indicates significant
difference between dsGFP- aphids and dsHRC -aphid saliva
treatment (P < 0.05). (n) Representative fluorescence
microscope images showing fluorescence of Ca2+ signal
in N. benthamiana leaves infiltrated by dsGFP- aphid (the
middle panel) and dsHRC -aphid saliva (the lower panel). Control
(the upper panel): 15% sucrose solution treatment. Bars = 100 μm. The
data shown are mean ± standard error (SEM). * above the bars indicate
significant differences among different treatments at P < 0.05
(t-test, *P < 0.05, **P < 0.01, *** P <
0.001).
Fig 5. ApHRC expression promoted aphid
performance.
(a-b) EPG results of ApHRC -silenced Serratia -infected
aphids for 8 h on EV: empty vector, and OEHRC : overexpression ofApHRC M. truncatula . (a) Time spent on salivary secretion
into sieve elements (E1 wave) (n=10). (b) Ingestion time (E2 wave)
(n=10). (c-g) Relative expression levels of EV and OEHRC M.
truncatula JA and SA pathway genes induced by ApHRC -silencedSerratia -infected aphids. (c) PAL , phenylalanine ammonia
lyase; (d) NPR1 , nonexpresser of PR genes 1; (e) PR1 ,
pathogenesis-related protein 1; (f) LOX2 , lipoxygenase 2; (g)AOS2 , allene oxide synthase 2. (h)
H2O2 concentration of EV and
OEHRC M. truncatula leaves induced by 10ApHRC -silenced Serratia -infected aphids, respectively for
6 h (n=6). (i) Subcellular localization of fluorescent probes, DCFH-DA,
in leaves of EV (the middle panel) and OEHRC (the lower panel)M. truncatula infiltrate by ApHRC -silencedSerratia -infected aphids. Control (the upper panel): 15% sucrose
solution treatment. Bars = 100 μm. The data shown are mean ± standard
error (SEM). * above the bars indicate significant differences among
different treatments at P < 0.05 (t-test, *P < 0.05,
**P < 0.01, ***P < 0.001).
Fig 6. S. symbiotica influence on pea aphid
MRGR, fecundity and development time.
(a) MRGR of Serratia -infected (Serratia +) andSerratia -free (Serratia -) aphids (n=50). (b) Fecundity ofSerratia -infected and Serratia -free aphids (n=50). (c)
Nymphal duration of Serratia -infected and Serratia -free
aphids (n=50). Data shown are mean ± standard error (SEM). * above the
bars indicate significant differences among different treatments at P
< 0.05 (t-test, *P < 0.05, **P < 0.01,
***P < 0.001).