Guangxi Tianyuan Biochemical Co., Ltd.

Rapeseed is a globally important economic crop that can be severely impacted by aphids. However, our understanding of rapeseed resistance to aphid stress is very limited. In this study, we analyzed the resistance characteristics of the low aphid-susceptible variety APL01 and the highly aphid-susceptible variety Holly in response to aphid stress. APL01 had a more significant inhibitory effect on aphid proliferation compared with Holly during the early stage of inoculation, whereas Holly showed stronger tolerance to aphid stress compared with APL01 during the later stage of inoculation. Through transcriptome, physiological, and gene expression analyses, it was revealed that chitinase activity, catalase activity, calcium signal transduction, and activation of systemic acquired resistance might be involved in aphid resistance in B. napus. The degree of inhibition of photosynthesis in plants under aphid stress directly determines the tolerance of B. napus to aphid stress. Furthermore, four promising candidate genes were screened from eight genes related to rapeseed response to biotic stress through RT-qPCR analysis of gene expression levels. These research findings represent an important step forward in understanding the resistance of rapeseed to aphid stress and provide a solid foundation for the cloning of genes responsible for this resistance.

The present experiment was conducted to prepare cyhalothrin solid dispersions, and investigate their solubilization effect on cyhalothrin and their dissolution characteristics of cyhalothrin.With polyethylene glycol 6000 (PEG-6000), polyethylene glycol 20000 (PEG-20000) and polyvinylpyrrolidone K30 (PVP-K30) as carriers, the cyhalothrin solid dispersions were prepared by using solvent-melting and solvent methods, resp.The UV spectrometry methods were used to determinate solubility and dissolution rate of cyhalothrin solid dispersions.And UV spectrum, FTIR and SEM methods were used to characterize structures of solid dispersions.Finally, the absorption method was used to determinate biol. activity of solid dispersions against corn borer.The solubility of cyhalothrin in solid dispersions was significantly increased, compared with those of cyhalothrin and phys. mixture of cyhalothrin and carrier with same mass ratio, particularly, PVP-K30 had best solubilization effect on cyhalothrin, thus the solubility of cyhalothrin was increased from 0.0050 mg/L to 28.1776 mg/L.Furthermore, the results of phase anal. indicated that cyhalothrin was highly dispersed in carriers as amorphous state.The results of toxicity test showed that the solid dispersions had some insecticidal effect, and their insecticidal activity was higher than 2.5% cyhalothrin microemulsion.The solubility of cyhalothrin can be greatly improved by cyhalothrin solid dispersions with PEG-6000, PEG-20000 and PVP-K30 as its carriers.Furthermore, these cyhalothrin solid dispersions have more insecticidal effect, and should be applied in actual agricultural production

A method for separation and quant. anal. of Dufulin TC by HPLC with methanol and water as mobile phase, ZORBAX SB-C₁₈ column (250 mm × 4.6 mm, 5 μm) and diode array detector (DAD) at 270 nm wavelength was described.The result showed that the linear correlation coefficient was 0.9999, the standard deviation was 0.17, the variation coefficient was 0.17%, and the average recovery was 100.0%.