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Plutella xylostella (L.), a worldwide vegetable pest, has developed resistance to spinetoram, which was previously effective for the control of P. xylostella (L.). The insecticidal resistance mechanism is essential to develop effective resistance management strategies. To explore the spinetoram resistance mechanism, a comparative proteomics approach was used to investigate the proteomic differences between the spinetoram-susceptible strain (SS) and spinetoram-resistant strain (RS) of P. xylostella (L.). Approximately 280 protein spots were detected on each SDS-PAGE gel. Of these, 19 proteins were successfully identified by MALDI-TOF-MS.·There were 6 significantly down-regulated spots and 13 up-regulated spots in RS, which showed significantly difference compared to that in SS. Based on the gene ontology(GO) system and KEGG database, the 19 identified proteins were classified into 6 groups including metabolisms, signal transduction, chaperones, transcriptional, protein synthesis, structural protein. Meanwhile, the expression profiles of 5 resistant related protein were further analysed by qRT-PCR. The results showed that 60S acidic ribosomal protein P2, glutathione S-transferase isozyme 3 and glutathione S-transferase delta were significantly up-regulated, while phosphoglycerate mutase and receptor for activated protein kinase C homolog were significantly down-regulated. The expression tendency of mRNA was in accordance with which of protein. This study provided evidences that spinetoram induces proteomic changes in P. xylostella (L.), and it is contributed to help us understand the resistance mechanism of P. xylostella (L.) to spinetoram. [ABSTRACT FROM AUTHOR]

Phalaenopsis orchid is among the most valuable ornamental flowering plants in the world. Since visible damage substantially decreases its amenity, limited damage is allowed in its production. An unknown insect species (Diptera: Sciaridae) was found to cause serious damage to the seedling of the Phalaenopsis orchid in greenhouses in Guangdong, China. The insect occurred in high populations in almost all greenhouses that grow Phalaenopsis orchid and the number of sciarid adults trapped on a yellow sticky card could reach as many as 303 in 24 h. An effective management strategy on any pest requires an accurate identification. Therefore, it is urgent to identify this pest correctly to mitigate its damage to the industry. Damage to Phalaenopsis orchid and morphological characteristics of the pest was described in this study. Molecular analyses based on the 488-bp portion of the mitochondrial DNA from the cytochrome oxidase I(mt COI ) region were conducted to supplement morphological characteristics in identifying this pest. Both morphological characteristics and phylogenetic tree constructed with mt COI genes identified this sciarid as Bradysia difformis Frey, 1948 (= Bradysia paupera Tuomikoski, 1960) (Diptera: Sciaridae). A literature search indicated that B. difformis has been a common pest of greenhouse and forestry nurseries in Europe and South Africa. Our study is the first record of B. difformis damaging Phalaenopsis orchid in China. [ABSTRACT FROM AUTHOR]

Semen Ziziphus jujube (SZJ), the seeds of Ziziphus jujuba Mill. var. spinosa, is a kind of traditional Chinese medicine used for its action on insomnia. In order to analyze the effective component, we investigated and compared the sedative and hypnotic effects of three kinds of compounds, flavonoids, saponins, and polysaccharides. Flavonoids, saponins, and polysaccharides were extracted from SZJ and orally administered to mice separately at 17 g kg-1 per day for certain days before animal tests. Spontaneous motility and coordinated movement tests were used to observe the effects of the three kinds of compounds on the mouse behavior, and sodium barbital-induced sleeping time of mouse were tested to analyze the effects of the three kinds of compounds on the sleep of mouse. Results show that flavonoids and saponins caused a significant reduction of walking time and coordinated movement ability of mouse, significantly prolonged its sleeping time at 40 mg kg-1, ip, subthreshold dose and increased the sleeping number of animals at 50 mg kg-1, ip, superthreshold dose induced by coeliac injection of sodium barbital. Polysaccharides did not show any significance in all animal tests. Comparative analysis showed that saponins had a more effective sedative and hypnotic function than that of flavonoids, polysaccharides did not show a sedative and hypnotic effect. [ABSTRACT FROM AUTHOR]