Table 1.
Abundance of secondary bacterial endosymbionts in the efficiently transmitting Bemisia tabaci 63 and the poor transmitter B. tabaci 95.
Figure 1.
Uptake of WmCSV by the efficient transmitter Bemisia tabaci 63 and the poor transmitter B. tabaci 95.
Virus concentrations were analyzed by qPCR in composite samples of 100 whiteflies of B. tabaci 63 (B.t. 63) and B. tabaci 95 (B.t. 95) after a six hour starvation over an acquisition access period of five days (two technical replicates). Median values of virus concentrations were calculated assuming 100 ng DNA as an average DNA content of an individual whitefly. Three independent experiments were performed.
Figure 2.
WmCSV and TYLCV concentrations in host plants and insects of B. tabaci 63 and 95.
Viruses were quantified in watermelon (Wm), tomato (To) and insects (B.t.) after an acquisition access period of 5 d by qPCR following 2 d feeding on cotton for discharge of the intestine (n = 18, with two technical replicates each). Virus concentrations were calculated assuming 100 ng DNA as an average DNA content of an individual whitefly. Solid horizontal lines within boxes represent the median; dashed horizontal lines represent mean values; boxes contain values between the 25th and 75th quartiles; the antennae represent 95 percent of all data; dots represent outliers. Asterisks with the same number indicate significant differences between the samples (Student's t-test, p<0.05).
Figure 3.
WmCSV and TYLCV concentrations in insects of B. tabaci 63 and 95 after artificial feeding.
Whiteflies were fed on artificial medium adjusted to similar concentrations of purified WmCSV and TYLCV. Feeding experiments were kept for 48 h under greenhouse conditions followed by two days incubation on cotton for discharge (n = 12, with two technical replicates each). Mean values of virus concentrations were calculated assuming 100 ng DNA as an average DNA content of an individual whitefly. Asterisks indicate significant differences between both whitefly populations having taken up the same virus (Student's t-test, p<0.05).
Figure 4.
WmCSV and TYLCV concentrations in organs of B. tabaci 63 and 95.
Viruses were quantified in excised midguts (A) and salivary glands (B) of B. tabaci (B.t.) after 5 d acquisition access period and 2 d discharge by qPCR (Single midguts represent one sample; n = 36, with two technical replicates each; ten primary salivary glands represent one sample; n = 18, with two technical replicates each). Specification of box plots is given in the legend to Figure 3. Asterisks indicate significant differences between the whitefly populations (Student's t-test, p<0.05).
Table 2.
Translocation of WmCSV and TYLCV into the hemolymph of the efficiently transmitting Bemisia tabaci 63 and the poor transmitter B. tabaci 95.
Figure 5.
Localization of WmCSV and TYLCV in excised midguts of B. tabaci 63 and 95.
Viruses were localized after a 5 d acquisition access period and 2 d discharge using fluorescent in situ hybridization. Left column: virus localization using specific probes (red); right column: transmitted light images. WmCSV in B. tabaci 63 (A, B) and in B. tabaci 95 (C, D); TYLCV in B. tabaci 63 (E, F) and B. tabaci 95 (G, H); WmCSV in B. tabaci 63 after fluorescent in situ hybridization and nuclei staining with DAPI (I, J). CA, caeca; FC, filter chamber; DM, descending midgut; AM, ascending midgut; HG, hindgut. Arrowheads: virus accumulations.
Figure 6.
Localization of WmCSV and TYLCV in excised primary salivary glands of B. tabaci 63 and 95.
Viruses were localized after a 5 d acquisition access period and 2 d discharge by fluorescent in situ hybridization. Left column: virus localization using specific probes (red); right column: transmitted light images. WmCSV in B. tabaci 63 (A, B) and in B. tabaci 95 (C–F); TYLCV in B. tabaci 63 (G, H) and B. tabaci 95 (I, J). DS, ducal section of the central region; EC, endcap; SS, secretory section of the central region.
Figure 7.
WmCSV and TYLCV concentrations in single whiteflies and excised organs of the poorly transmitting B. tabaci 95 and the non-transmitter B. tabaci 95-.
WmCSV (A) and TYLCV (B) were quantified in individual whiteflies, individual midguts and primary salivary glands (10 primary salivary glands represent one biological sample) after 5 d acquisition access period and 2 d discharge by qPCR (B. tabaci 95: n = 4, with two technical replicates each; B. tabaci 95-: n = 18 individual whiteflies, n = 36 individual midguts, n = 20 primary salivary glands, with two technical replicates each). Specification of box plots is given in the legend to Figure 2. Asterisks indicate significant differences between the parental population B. tabaci 95 and B. tabaci 95- (Student's t-test, p<0.05).