Performance of Bt-susceptible and -heterozygous genotypes of Spodoptera frugiperda (J.E. Smith) possessing single- or dual-gene resistance alleles in sequential feedings of non-Bt and Cry1A.105/Cry2Ab2 maize leaf tissues

Yiwan Zhou; Ying Niu; Graham P Head; Paula A Price; Fangneng Huang

doi:10.1016/j.jip.2018.10.002

Performance of Bt-susceptible and -heterozygous genotypes of Spodoptera frugiperda (J.E. Smith) possessing single- or dual-gene resistance alleles in sequential feedings of non-Bt and Cry1A.105/Cry2Ab2 maize leaf tissues

J Invertebr Pathol. 2018 Nov:159:105-112. doi: 10.1016/j.jip.2018.10.002. Epub 2018 Oct 3.

Authors

Yiwan Zhou¹, Ying Niu², Graham P Head³, Paula A Price³, Fangneng Huang⁴

Affiliations

¹ College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China; Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
² Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
³ Monsanto Company, St. Louis, MO 63167, USA.
⁴ Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA. Electronic address: fhuang@agcenter.lsu.edu.

PMID: 30291865
DOI: 10.1016/j.jip.2018.10.002

Abstract

We simulated larval feeding behavior in seed blends of non-Bt and Bt maize to determine if seed blends create more favorable conditions for heterozygous-resistant insects over their Bt-susceptible counterparts. Survival, growth, development, and progeny production of four genotypes of the fall armyworm, Spodoptera frugiperda, Bt-susceptible (aabb), Cry1A.105 heterozygous resistant (Aabb), Cry2Ab2 heterozygous resistant (aaBb), and Cry1A.105/Cry2Ab2 heterozygous resistant (AaBb), were evaluated in eight feeding sequences (Seq 1-8) of non-Bt and MON89034 Bt maize leaf tissue expressing the Cry1A.105 and Cry2Ab2 proteins. We report variation in the performance of the four genotypes across the feeding sequences and biological parameters measured. Three heterozygous genotypes generally outperformed the susceptible genotype in larval survival, pupation rate, pupal weight, and progeny production. The performance was greater for Aabb over aaBb, AaBb over Aabb or aaBb, in two of the feeding sequences. The findings of this study could have important implications in assessing the risk of seed blends as refuge plantings for Bt crop resistance management where resistance in the target pest is not functionally recessive.

Keywords: Dual-Bt gene resistance; Fall armyworm; Resistance management; Seed blend.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Alleles
Animals
Bacterial Toxins / genetics
Genotype
Insecticide Resistance / genetics*
Pest Control, Biological / methods*
Plant Leaves / parasitology
Plants, Genetically Modified / genetics
Plants, Genetically Modified / parasitology*
Spodoptera / genetics*
Zea mays / parasitology*

Substances

Bacterial Toxins