Insecticide Susceptibility and Mechanism of Spodoptera frugiperda on Different Host Plants.

Spodoptera frugiperda (J. E. Smith) is a worldwide economically important crop pest. Although the individuals of S. frugiperda that invaded China have been characterized as the corn strain, they also have the ability to damage other crops in China. The physiological and behavioral responses of S. frugiperda to different host plants are poorly understood. In the present study, we investigated the host plant preference, fitness costs, and differences in detoxification gene expression and microbiome composition between two S. frugiperda strains that fed on different crop plant diets. The results showed that S. frugiperda larvae exhibited no obvious preference for corn or rice, but significant suppression of development was observed in the rice-fed strain. In addition, the corn-fed strain showed higher insecticide tolerance and detoxification enzyme activities than the rice-fed strain. Moreover, multiple detoxification genes were upregulated in the corn-fed strain, and microbiome composition variation was observed between the two strains. Together, the results suggest that population-specific plasticity is related to host plant diets in S. frugiperda. These results provide a theoretical basis for the evolution of resistance differences in S. frugiperda and are helpful for designing resistance management strategies for S. frugiperda aimed at different crops.

Dual stimuli-responsive fungicide carrier based on hollow mesoporous silica/hydroxypropyl cellulose hybrid nanoparticles.

The controlled release of pesticides based on nanoparticle platforms has emerged as a new technology for increasing the efficiency of pesticides and for reducing environmental pollution because of their size-dependent and target-modifying properties. In the present study, pH/cellulase dual stimuli-responsive controlled-release formulations (PYR-HMS-HPC) were designed by grafting hydroxypropyl cellulose onto pyraclostrobin-loaded hollow mesoporous silica nanoparticles via an ester linkage. The PYR-HMS-HPC formulations were characterized by Fourier transform infrared spectroscopy, thermogravimetric analyzer, transmission electron microscope and scanning electron microscope. The results demonstrated that PYR-HMS-HPC with a loading capacity of 12.1 wt% showed excellent pyraclostrobin release behaviors in response to acidic environments and the introduction of cellulase, could effectively prevented pyraclostrobin from photolysis. Compared with commercial pyraclostrobin formulations, the PYR-HMS-HPC formulations showed much stronger and statistically significant fungicidal activity against Magnaporthe oryzae from 7 to 21 days. Furthermore, the Allium cepa chromosome aberration assay demonstrated that the PYR-HMS-HPC formulations reduced the genotoxicity of pyraclostrobin. These pH/cellulase dual stimuli-responsive controlled-release formulations are of great interest for sustainable on-demand crop disease protection.

Genome-wide identification and characterization of Glyceraldehyde-3-phosphate dehydrogenase genes family in wheat (Triticum aestivum).

BACKGROUND: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a central enzyme in glycolysi, we performed genome-wide identification of GAPDH genes in wheat and analyzed their structural characteristics and expression patterns under abiotic stress in wheat. RESULTS: A total of 22 GAPDH genes were identified in wheat cv. Chinese spring; the phylogenetic and structure analysis showed that these GAPDH genes could be divided into four distinct subfamilies. The expression profiles of GAPDH genes showed tissue specificity all over plant development stages. The qRT-PCR results revealed that wheat GAPDHs were involved in several abiotic stress response. CONCLUSIONS: Wheat carried 22 GAPDH genes, representing four types of plant GAPDHs (gapA/B, gapC, gapCp and gapN). Whole genome duplication and segmental duplication might account for the expansion of wheat GAPDHs. Expression analysis implied that GAPDHs play roles in plants abiotic stress tolerance.