Identification and Evaluations of Novel Insecticidal Proteins from Plants of the Class Polypodiopsida for Crop Protection against Key Lepidopteran Pests.

Weiping Xie,Lisa Procyk,Eric Schepers,Matthew J Heckert,Ryan Gerber,Scott H Diehn,James Le,Adane Kassa,Nasser Yalpani,Xiuli Qi,Carol Pilcher,Nuria Jiménez-Juárez,Amy Lum,Lu Liu,Changkui Ding,Mark E Nelson,Russ Booth,Virginia C Crane,Genhai Zhu,Jarred Oral,Fikru J Haile ,Janet C Rice ,T M Nowatzki ,Minh Quang Nguyen ,Jennifer K Barry ,Alejandra Cortés Pascual ,Albert Lu ,Howard G Damude ,Guangyu Wu

doi:10.3390/toxins11070383

Abstract

Various lepidopteran insects are responsible for major crop losses worldwide. Although crop plant varieties developed to express Bacillus thuringiensis (Bt) proteins are effective at controlling damage from key lepidopteran pests, some insect populations have evolved to be insensitive to certain Bt proteins. Here, we report the discovery of a family of homologous proteins, two of which we have designated IPD083Aa and IPD083Cb, which are from Adiantum spp. Both proteins share no known peptide domains, sequence motifs, or signatures with other proteins. Transgenic soybean or corn plants expressing either IPD083Aa or IPD083Cb, respectively, show protection from feeding damage by several key pests under field conditions. The results from comparative studies with major Bt proteins currently deployed in transgenic crops indicate that the IPD083 proteins function by binding to different target sites. These results indicate that IPD083Aa and IPD083Cb can serve as alternatives to traditional Bt-based insect control traits with potential to counter insect resistance to Bt proteins.

Highlights

Many lepidopteran insect species are economically important pests of crops worldwide
Transgenic crops deployed for insect control contained Bacillus thuringiensis (Bt) proteins functioning with only a single mode of action (MoA) for each of the key pests [7,8,9]
The evolution of insect resistance to these Bt proteins, when previously deployed as a single MoA, can limit the durability improvements realized from this strategy [8,9]

Summary

Introduction

Many lepidopteran insect species are economically important pests of crops worldwide. The feeding damage caused by corn earworm (CEW, Helicoverpa zea) and fall armyworm (FAW, Spodoptera frugiperda)), Toxins 2019, 11, 383; doi:10.3390/toxins11070383 www.mdpi.com/journal/toxins. Vip3Aa have been very effective against lepidopteran pests in transgenic corn, soybean, and cotton (Gossypium hirsutum) [5,6]. Transgenic crops deployed for insect control contained Bt proteins functioning with only a single mode of action (MoA) for each of the key pests [7,8,9]. The evolution of insect resistance to these Bt proteins, when previously deployed as a single MoA, can limit the durability improvements realized from this strategy [8,9]. A survey of recently published literature on insect resistance to

Methods

Results

Conclusion