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[Objectives] Female Ericerus pela can secrete a considerable amount of honeydew during the incubation period. We previously found that this honeydew was prone to contamination by certain fungi. However, the biological significance of the honeydew secreted by female E. pela is still largely unclear. This study aimed to understand the composition of the honeydew secreted by E. pela, and provide an overview of gene expression in female adults during this period. We hope the results will lead to a deeper understanding of the biological significance of honeydew secretion by E. pela. [Methods] The transcriptome of incubating female E. pela period was sequenced and the metabolome of the honeydew secreted by females was analyzed. [Results] The single greatest component of honeydew was maltitol, followed by galactositol, trehalose, triose and other sugars. Honeydew also contained a small amount of various amino acids, fats, vitamins, and other metabolites or secondary metabolites. Combining the transcriptome and metabolomic data revealed that the main pathways were "metabolic", "carbon" and "biosynthesis of amino acids". The gene family related to 'N-glycan biosynthesis', and another containing the gene Q96JB1 with the corresponding metabolites citrate, orotate and L-glutamate, were contracted. [Conclusion] The main components of the honeydew secreted by E. pela are not beneficial for parasitic biological control agents or for mutualism with other insects. Some gene families related to the components of honeydew have been contracted. These results show that the honeydew secreted by E. pela contains unnecessary metabolites, or may be harmful to female E. pela. [ABSTRACT FROM AUTHOR]

Abstract: In order to clarify the sensitivity of Sogatella furcifera to cycloxaprid at different temperatures, the toxicity of cycloxaprid to S. furcifera at different temperatures from 18 °C to 32 °C was determined by leaf dipping method. The effects of temperatures on the secretion of honeydew and detoxification enzymes (EST, P450 and GSTs) were also detected. The results showed that cycloxaprid was a positive temperature coefficient insecticide. The toxicity of cycloxaprid against S. furcifera increased with temperature. The toxicity of cycloxaprid against S. furcifera at 32 °C was 15.6 times as high as that at 18 °C. The feeding capacity and the amount of honeydew excretion increased with the increase of temperature. The activities of EST and P450 of S. furcifera also changed with temperature. With the elevation of temperature, the activity of EST increased first and then decreased. The P450 enzyme activity decreased at higher temperature. However, the activity of GSTs has no significant difference under different temperatures. The susceptibility variation of S. furcifera to cycloxaprid under different temperatures is closely related to its feeding capacity and detoxification activity (EST and P450). The above study provides a scientific reference for the rational use of cycloxaprid in the field under different environmental temperatures. [ABSTRACT FROM AUTHOR]

The resistance of several new rice varieties (combinations) to rice brown planthopper (BPH) was evaluated by using seedling screening test, honeydew measurement in different rice stages and field investigation of BPH populations in adult-plant stage. The results of seedling screening test showed that R339 (Bph14 + Bph15) was moderately resistant to BPH, while other varieties ( combinations) were susceptible to BPH. The results of honeydew measurement in different rice stages indicated that the resistance of R339 ( Bph14 + Bph15) and R838 ( Bph14 + Bph15 ) to BPH was not significantly different from that of RHT from 30 days of seedling age. The resistance of R339 ( Bph15 ), Liangfengyou339 ( Bph14 + Bph15) and Liangfengyou838 ( Bph14 + Bph15 ) to BPH was not significantly different from that of RHT from 40 days of seedling age. The resistance of R339 ( Bph14 ) and Liangfengyou339 ( Bph15 ) to BPH was not significantly different from that of RHT from 60 days of seedling age. The resistance of Liangfengyou 339 ( Bph14) to BPH was not significantly different from that of RHT in 70 days of seedling. The results of field investigation in adult-plant stage showed that when there was large population in field，the BPH populations densities in restores lines including R339 ( Bph15 ), R339 ( Bph14 + Bph15), R838 ( Bph14 + Bph15) and hybrid rice combinations including Liangfengyou339 ( Bph14 ), Liangfengyou339 ( Bph15 ), Liangfengyou339 ( Bph14 + Bph15 ), Liangfeng -you838 ( Bph14 + Bph15) were significantly lower than those in varieties (combinations) with no resistance gene, and those varieties ( combinations ) in adult-plant stage showed obvious resistance to BPH. R339 ( Bph15 ), R339 ( Bph14 + Bph15 ) ， R838 ( Bph14 + Bph15 ), Liangfeng-you339 ( Bph14 ), Liang- fengyou339 ( Bph15 ), Liang- fengyou339 ( Bph14 + Bph15 ), Liangeng-you838 ( Bph14 + Bph15 ) had application value in rice production in Guangxi. [ABSTRACT FROM AUTHOR]

From October 2008 to May 2010, an investigation was made in a lac plantation in Yayi region of Mojiang County, Yunnan Province, China, aimed to understand the behavior of the monopolization of honeydew sources by ant Crematogaster macaoensis, and its effects on the sex ratio, mortality, fecundity, and lac production of Yunnan lac insect Kerria yunnanensis. The results showed that C. macaoensis fed and monopolized the honeydews around the clock during the whole life cycle of K. yunnanensis on the stick-lac, and the average number of visiting C. macaoensis ranged from 16.8±2.3 to 39.3±10.0 per 10 cm length of the stick-lac. C. macaoensis constructed shelters to prevent other animals from visiting the lac insect. C. macaoensis monopolization reduced the lac production of individual K. yunnanensi significantly, but had no significant effects on the lac production of whole lac insect colony. In addition, C. macaoensis monopolization reduced the mortality of K. yunnanensis significantly, and increased the percentage of K. yunnanensis females and the adult female fecundity. It was concluded that ant monopolization of the lac insect honeydew seemed to be beneficial to the lac production by the Yunnan lac insect. [ABSTRACT FROM AUTHOR]