Abstract
Plant bugs (Miridae
species), which are sap-sucking insects, have emerged as major pests of cotton
in China. Most Miridae species are not sensitive to commercial Bacillus
thuringiensis (Bt) cotton, resulting in significant economic losses and an
increased application of insecticide, which eventually may compromise the
future of Bt cotton. We demonstrate that FATTY ACYL-COA REDUCTASE (AsFAR) plays
an essential role in the reproduction of the bug Adelphocoris suturalis.
Down-regulation of AsFAR expression by injection of double-stranded RNA
suppresses ovarian development and female fertility, resulting in females
producing few viable offspring. To determine the viability of an RNA
interference approach to limit FAR expression and reproductive ability in
A. suturalis, a dsRNA targeting the AsFAR gene (dsAsFAR) of
A. suturalis was expressed in transgenic cotton plants. AsFAR
transcription levels were significantly downregulated in A. suturalis
feeding on the transgenic plants. In contained field trials, the transgenic
cotton lines significantly suppressed the development of A. suturalis
populations and were resistant to damage caused by plant bug infestation. These
results suggest a new strategy for the management of plant bug pests of cotton