RNAi Technology Targets Corn Rootworm
Farmers looking to gain the upper hand over corn rootworm (CRW) pests have new tools to deploy in the field, thanks to Ribonucleic acid interference (RNAi) technology.
RNAi works in CRW as it feeds on corn roots by turning off functions the pest needs for development.
Companies including Bayer Crop Science and Corteva Agriscience introduced RNAi in corn hybrids this year. Both organizations plan to ramp up production for broader farmer adoption in 2023.
A TRIPLE THREAT
The first products with RNAi technology to fight CRW were launched commercially this season by Bayer as SmartStax PRO hybrids in the 95- to 115-day maturity range.
The hybrids offer three modes of action (MOAs) for control – two Bt traits Cry3Bb1 and Cry34Ab1/Cry35Ab1 [now reclassified as Gpp34Ab1/Tpp35Ab1] and the new MOA called DvSNf7 dsRNA.
In addition to CRW, Bayer says SmartStax Pro provides protection against above-ground pests including European corn borer, southwestern corn borer, fall armyworm, black cutworm and corn earworm.
SIX MODES OF ACTION
Corteva is offering farmers its new Vorceed Enlist corn hybrids, containing a novel RNAi active ingredient to control corn rootworm. Vorceed Enlist is available in a range of 93- to 100-day relative maturity hybrids, according to Tony Klemm, Corteva vice president, corn portfolio.
The hybrids offer three MOAs for both above-ground insect protection and below-ground insect protection (plus tolerance to four herbicide MOAs to help manage resistant weeds, 2,4-D choline, glyphosate, glufosinate and FOP herbicides).
The company reports reduced corn root damage and a 99% reduction in adult beetle emergence, thanks to the layered MOAs.
“We’re seeing improved performance, because our root protection is 17% better, on average,” Klemm says. “That is what’s helping us get the yield lift, which we’ll be able to tie into our large germplasm pool. This product will be our leading corn rootworm trait offer in our portfolio by mid-decade.”
The RNAi technology, he adds, is expected to be available across all Corteva seed brands, including Pioneer, Brevant Seeds, AgVenture, Dairyland Seed, Hoegemeyer, NuTech and Seed Consultants.
LOOKING AHEAD
Earlier this year, Bayer received EPA commercial registration for traits in its newest corn product, VT4Pro with RNAi. It helps control above-and below-ground pests including corn earworm, western bean cutworm and CRW. The company expects to launch commercially as early as 2024.
Rhonda Brooks leverages 35 years of experience and farm roots to report on seeds, agronomy and inputs.
