Location: Biological Control of Pests ResearchTitle: Association of insect-derived ear-injury with yield and Aflatoxin of corn hybrids varying in Bt expression.
|BREWER, MICHAEL - Texas Agrilife|
|PRUTER, LUKE - Texas Agrilife|
|MURRAY, SETH - Texas Agrilife|
|ISAKEIT, THOMAS - Texas Agrilife|
|BENRAL, JUNO - Texas Agrilife|
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/3/2019
Publication Date: N/A
Interpretive Summary: A series of related corn hybrids with a range of transgenic insect protection were planted in a water-, heat-, and insect-stressed environment to evaluate the effectiveness of this protection against insect damage and aflatoxin contamination. Data was collected from 2 field sites and 4 years. The most effective available insect protection confered significant reduction in insect injury and reduced, but still high, aflatoxin contamination.
Technical Abstract: Corn, Zea mays L., hybrids, differing in the expression of Bacillus thuringiensis (Bt) transgenes were planted over a 4-year period in two locations from 2014 - 2017. Ear-injury, yield, and aflatoxin were measured across three Bt groups and where available two water-stress levels. The first group consisted of non-Bt hybrids which express no Bt transgenes and were used as a control for the other two Bt groups. The second group is comprised of hybrids that express one or more Cry-Bt transgenes. The third group of hybrids express one or more of the Cry-Bt transgenes as well as the vegetative insecticidal Bt protein making the Cry/Vip-Bt group. Across all years and locations Cry/Vip-Bt hybrids consistently experienced the lowest amounts of ear-injury and aflatoxin, however the effects on yield widely varied by location. As to date many environmental factors have been associated with the production of aflatoxin in corn. Transgenic Bt corn has not conclusively been shown to have an impact on aflatoxin accumulation in corn although it has been shown to reduce insect herbivory, and insect herbivory has been independently linked to increased plant-stress and subsequent aflatoxin production (Abbas et al. 2013). Our intentions are to explore the association of yield with ear-injury and Aspergillus (A.) flavus infection among hybrids with varying levels of Bt-toxins in different environments to identify experimental conditions and environments well suited for more intensive research in reducing corn risk to ear-insects and aflatoxin producing A. flavus.