RT-qPCR for Detection and Expression Monitoring of Core Genes Involved in the RNA Interference Pathways of Western Corn Rootworm (Diabrotica virgifera virgifera).

Reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays are a highly accurate and precise method for measuring transcript expression levels. A major drawback of RT-qPCR is the extensive optimization and validation necessary to produce high-quality assays, as described in the guidelines "Minimum Information for Publication of Quantitative Real-Time PCR Experiments." This chapter describes use of designed and optimized RT-qPCR assays that accurately detect expression of eight genes predicted to be centrally involved in the RNA interference (RNAi) pathways of western corn rootworm (WCR), and appropriate accompanying parameters.

Molecular characterization of the insecticidal activity of double-stranded RNA targeting the smooth septate junction of western corn rootworm (Diabrotica virgifera virgifera).

The western corn rootworm (WCR, Diabrotica virgifera virgifera) gene, dvssj1, is a putative homolog of the Drosophila melanogaster gene, snakeskin (ssk). This gene encodes a membrane protein associated with the smooth septate junction (SSJ) which is required for the proper barrier function of the epithelial lining of insect intestines. Disruption of DVSSJ integrity by RNAi technique has been shown previously to be an effective approach for corn rootworm control, by apparent suppression of production of DVSSJ1 protein leading to growth inhibition and mortality.

Identification and comparison of key RNA interference machinery from western corn rootworm, fall armyworm, and southern green stink bug.

RNA interference (RNAi)-based technology shows great potential for use in agriculture, particularly for management of costly insect pests. In the decade since the insecticidal effects of environmentally-introduced RNA were first reported, this treatment has been applied to several types of insect pests. Through the course of those efforts, it has become apparent that different insects exhibit a range of sensitivity to environmentally-introduced RNAs.

Knockdown of RNA interference pathway genes impacts the fitness of western corn rootworm.

Western corn rootworm (Diabrotica virgifera virgifera) is a serious agricultural pest known for its high adaptability to various management strategies, giving rise to a continual need for new control options. Transgenic maize expressing insecticidal RNAs represents a novel mode of action for rootworm management that is dependent on the RNA interference (RNAi) pathways of the insect for efficacy. Preliminary evidence suggests that western corn rootworm could develop broad resistance to all insecticidal RNAs through changes in RNAi pathway genes; however, the likelihood of field-evolved resistance occurring through this mechanism remains unclear.