Period duration of <i>Ae. aegypti</i> larval ecdysis.

<p>Symbols represent the cumulative percentage of specimens at different immature stages. Bars represent the standard deviation of three independent experiments. Arrows indicate the experimental points, defined in hours, as early (e), intermediate (int) and late (l) moments for each instar.</p

Novaluron inhibits <i>Ae. aegypti</i> adult emergence.

<p>(<b>A</b>) Dose-dependent effect of novaluron over emergence inhibition. EI₅₀ and EI₉₀ indicate novaluron concentrations resulting in emergence inhibition of 50 and 99% of adults, respectively. Black and white bars indicate death at larval and pupal stages, respectively (<b>B</b>) Percentage of surviving adults (males and females) after novaluron treatment (EI₅₀). Bars indicate mean and standard deviation of three experiments. Asterisks indicate significant differences (ANOVA, P<0.05).</p

Novaluron alters cuticular chitin presence in late L4 larvae.

<p>WGA-FITC labeling was used to detect chitin by fluorescence microscopy. (<b>A</b>, <b>B</b>) Control larvae exhibiting continuous cuticle labeling. (<b>C–F</b>) Novaluron EI₉₉ larvae show uneven cuticle labeling. Chitin labeling of cuticle in distinct regions of the larva is rather uniform (arrow in <b>C</b>; panel <b>D</b>), absent (asterisk in <b>C</b>; panel <b>E</b>) or irregular (arrowhead in <b>C</b>; panel <b>F</b>). Peritrophic matrix chitin labeling was not altered (<b>A</b>, <b>C</b>). Bar = 100 µm in <b>A</b>, <b>C</b> and 10 µm in <b>B</b>, <b>D–F</b>. All images were also recorded in bright field, in order to assure that images were in focus and that a cuticle was present (data not shown).</p

Novaluron modifies cuticle and epidermis aspect of <i>Ae. aegypti</i> larvae.

<p>DIC microscopy was performed on histological sections of late L4 larvae stained with HE. (<b>A</b>) Control. Note the close association among cuticle, epidermis and the subjacent fat body layer. (<b>B–D</b>) Novaluron EI₉₉. Cuticle presents a semitransparent and discontinuous aspect being detached from the epidermis (<b>B</b>); epidermis is thinner (<b>C</b>) or degenerated, with a rope-like cuticle (<b>D</b>). ct: cuticle, did: disorganized imaginal disc, ep: epidermis, fb: fat body.</p

Novaluron induces delay in the development of <i>Ae. aegypti</i> immatures.

<p>Symbols represent the cumulative percentage of specimens in relation to eliminated exuviae of the preceding instar: squares, triangles and lozenges indicate newly emerged L4, pupae and adults, respectively. (<b>A</b>) control; (<b>B</b>) EI₅₀ and (<b>C</b>) EI₉₉. Bars represent the standard deviation of three independent experiments. Arrow indicates the moment of novaluron administration (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030363#s2" target="_blank">Methods</a>).</p