Baseline Susceptibility and Laboratory Selection of Resistance to Bt Cry1Ab Protein of Chinese Populations of Yellow Peach Moth, Conogethes punctiferalis (Guenée)

Abstract

Yellow Peach Moth (YPM), Conogethes punctiferalis (Guenée), is one of the most destructive maize pests in the Huang-Huai-Hai summer maize region of China. Transgenic Bacillus thuringiensis (Bt) maize provides an effective means to control this insect pest in field trials. However, the establishment of Bt resistance to target pests is endangering the continued success of Bt crops. To use Bt maize against YPM, the baseline susceptibility of the local populations in the targeted areas needs to be verified. Diet-overlay bioassay results showed that all the fourteen YPM populations in China are highly susceptible to Cry1Ab. The LC50 values ranged from 0.35 to 2.38 ng/cm2 over the two years of the collection, and the difference between the most susceptible and most tolerant populations was sevenfold. The upper limit of the LC99 estimates of six pooled populations produced >99% larval mortality for representative eight populations collected in 2020 and was designated as diagnostic concentrations for monitoring susceptibility in YPM populations in China. Hence, we evaluated the laboratory selection of resistance in YPM to Cry1Ab using the diet-overlay bioassay method. Although the resistant ratio was generally low, YPM potentially could evolve resistance to Cry1Ab. The potential developmentof resistance by target pests points out the necessity to implement resistance management strategies for delaying the establishment of pest resistance to Bt crops.

Intestinal Bacterial Diversity and Functional Analysis of Three Lepidopteran Corn Ear Worm Larvae

“…In the corn ear stage, C. punctiferalis , H. armigera and O. furnacalis are three co-occurring pests that seriously affect the corn yield [ 34 , 35 , 36 ]. Recently, the C. punctiferalis has gradually aggravated and surpassed the O. furnacalis and H. armigera as the most important pest, especially in the Huang-Huai-Hai summer corn region [ 1 ]. In this study, we investigated the bacterial diversity and community composition of the three pests and the corn endophytic bacteria.…”

“…There are six major corn areas in China. The Huang-Huai-Hai summer corn region is China’s second-largest corn-producing area, comprising about 40% of the country’s cultivated area and yields [ 1 ]. Despite many other factors influencing corn productivity, pests have always been an important component that affect corn production [ 2 ].…”

“…[ 11 ]. Furthermore, the damage of C. punctiferalis has gradually increased recently, even more than O. furnacalis and H. armigera , especially in the Huang-Huai-Hai region [ 1 , 12 ]. All three pests are widely distributed in China [ 1 , 13 , 14 ].…”

Different Maize Ear Rot Fungi Deter the Oviposition of Yellow Peach Moth (Conogethes punctiferalis (Guenée)) by Maize Volatile Organic Compounds

“…The YPM is a generalist herbivorous insect that attacks more than 100 plant species, such as maize, chestnut (Castanea mollissima Blume, (Fagales: Fagaceae)), sunflower (Helianthus annuus L., (Campanulales: Compositae)), hawthorn (Crataegus pinnatifida Bunge, (Rosales: Rosales)), apple, and so on [19,20], and has become the most destructive maize pest in the Huang-Huai-Hai region of China in the last 20 years [21,22]. The YPM is a multivoltine species with three to four generations per year in North China that overwinters as diapausing larvae [23].…”

Functional roles of two novel P450 genes in the adaptability of Conogethes punctiferalis to three commonly used pesticides

“…It is one of the few polyphagous borer pests that not only damage woody plants, such as peach, apple, hawthorn and chestnut, but also feed on herbaceous plants, including maize, soybeans and cotton ( Stanley et al, 2009 ; Chen et al, 2018 ). In recent years, C. punctiferalis has caused severe damage, and it is now considered a dominant economic lepidopteran pest of summer corn fields in the Huanghuaihai Region of China ( Shwe et al, 2021b ). Currently, chemical control is commonly used to control lepidopteran pests in corn fields, including the widely used pesticides chlorantraniliprole, emamectin benzoate and lambda-cyhalothrin.…”