Figure 6
Dynamics of the bacteriocyte size during aphid development.
(a) Representative microscopy images of bacteriocyte cells at different developmental stages. Scale bars = 100 μm. (b) Variation in the volume of bacteriocytes, in relation to aphid developmental stage. Results are displayed as box plots where central lines represent the medians, boxes comprise the 25–75 percentiles and whiskers denote the range; n > 10 aphids per stage, for a total number of more than 4,000 bacteriocytes isolated and analyzed. Data were analyzed by the Kruskal-Wallis test, followed by a post hoc multiple comparisons test (Wilcoxon rank-sum test with Bonferroni correction). Developmental stages labeled with different letters are significantly different (P < 0.05). (c) Modeling of bacteriocyte volume dynamics during aphid development. The volume of the bacteriocyte tissue per aphid was determined as the product of the bacteriocyte number by the bacteriocyte mean volume. A logistic model was applied for the first part of the dynamics, followed by an exponentially decreasing model. Volume increasing, r and decreasing rates, l, are shown on the figure, with their 95% confidence interval. Shaded grey area indicates the laying period.
