Phosphor-converted white light-emitting diodes for indoor illumination need to be warm-white (i.e., correlated color temperature ,4000 K) with good color rendition (i.e., color rendering index .80). However, no single-phosphor, single-emitting-center-converted white light-emitting diodes can simultaneously satisfy the color temperature and rendition requirements due to the lack of sufficient red spectral component in the phosphors' emission spectrum. Here, we report a new yellow Ba 0.93 Eu 0.07 Al 2 O 4 phosphor that has a new orthorhombic lattice structure and exhibits a broad yellow photoluminescence band with sufficient red spectral component. Warm-white emissions with correlated color temperature ,4000 K and color rendering index .80 were readily achieved when combining the Ba 0.93 Eu 0.07 Al 2 O 4 phosphor with a blue light-emitting diode (440-470 nm). This study demonstrates that warm-white light-emitting diodes with high color rendition (i.e., color rendering index .80) can be achieved based on single-phosphor, single-emitting-center conversion.

To gain valuable insights into the gene interaction and the complex regulation system involved in the development of insecticide resistance in mosquitoes Culex quinquefasciatus, we conducted a whole transcriptome analysis of Culex mosquitoes following permethrin selection. Gene expression profiles for the lower resistant parental mosquito strain HAmCqG0 and their permethrin-selected high resistant offspring HAmCqG8 were compared and a total of 367 and 3982 genes were found to be up- and down-regulated, respectively, in HAmCqG8, indicating that multiple genes are involved in response to permethrin selection. However, a similar overall cumulative gene expression abundance was identified between up- and down-regulated genes in HAmCqG8 mosquitoes following permethrin selection, suggesting a homeostatic response to insecticides through a balancing of the up- and down-regulation of the genes. While structural and/or cuticular structural functions were the only two enriched GO terms for down-regulated genes, the enriched GO terms obtained for the up-regulated genes occurred primarily among the catalytic and metabolic functions where they represented three functional categories: electron carrier activity, binding, and catalytic activity. Interestingly, the functional GO terms in these three functional categories were overwhelmingly overrepresented in P450s and proteases/serine proteases. The important role played by P450s in the development of insecticide resistance has been extensively studied but the function of proteases/serine proteases in resistance is less well understood. Hence, the characterization of the functions of these proteins, including their digestive, catalytic and proteinase activities; regulation of signaling transduction and protein trafficking, immunity and storage; and their precise function in the development of insecticide resistance in mosquitoes will provide new insights into how genes are interconnected and regulated in resistance.

To better understand the sublethal effects of cyantraniliprole on the black cutworm Agrotis ipsilon (Lepidoptera: Noctuidae), several studies were carried out to investigate sublethal effects on development stages, population parameters, feeding indices and nutrient content of A. ipsilon. The result of a bioassay showed that cyantraniliprole had high toxicity against A. ipsilon fourth-instar larvae with an LC50 of 0.354 μg.g−1 using an artificial diet. Compared with controls, sublethal doses of cyantraniliprole at LC5, LC20 and LC40 levels prolonged larval and pupal duration and extended mean generation time and total preovipositional period. In addition, survival rate, reproductive value, intrinsic and finite rates of increase and net reproduction rate declined significantly. Meanwhile, cyantraniliprole had markedly antifeedant effects; decreased the relative growth rate (RGR), the relative consumption rate (RCR), the efficiency of conversion of ingested food (ECI), the efficiency of conversion of digested food (ECD); and increased the approximate digestibility (AD) significantly. This phenomenon contributed to the decrease of nutrient contents, including lipids, protein and carbohydrates, to the point that insufficient energy was available for normal growth. Therefore, sublethal concentrations of cyantraniliprole decreased growth speed and reduced population reproduction of A. ipsilon. This result provides information useful in integrated pest management (IPM) programs for A. ipsilon.

The size of microcapsules (MCs) is an important and easily adjustable parameter; however, the function of this parameter in the movement behavior of pesticide MCs had not yet been studied. Phoxim-loaded polyurethane MCs with three various size distributions (average diameters of 1.39 μm, MC-S; 5.78 μm, MC-M; and 23.60 μm, MC-L) were obtained. In the greenhouse experiment, the insecticidal activities of MC-S and MC-M occurred mainly in the first 3 days and that of MC-L was maintained from 3 to 10 days after application. The direct and secondary distributions of a pesticide were defined and used to investigate the effects of particle size on the insecticidal activity of MCs in the field. The results indicated that the reason why MC-S had an excellent initial activity was that it was more widely distributed on the surface of the organism, was more likely to be adhered to by pests, and had greater resistance to rain washing. MC-L had excellent later-stage insecticidal activity, which was mainly because of its outstanding light stability. Then, retained phoxim was released through a crack caused by a light shining onto the shell. The increase in the size of the MCs improved the amount of pesticide swallowed by the insect and the movement distance of the pesticide within the digestive system of the insect. Thus, increasing the size of MCs helps increase the utilization rate of pesticides if a chemical group responding to alkaline conditions can be added into the capsule shell. The transfer and release behavior of pesticide MCs in the field can be regulated by simply adjusting the particle size, which is of great value to the application of pesticide MCs in agriculture and could provide a new approach for the efficient utilization of pesticide MC formulation.

Botanical nematicides have recently received increasing interest because of the high risks of some traditional nematicides to human health and the environment. This study evaluated the nematicidal activity of a plant volatile, trans-2-hexenal, against Meloidogyne incognita. This compound exhibited higher activity in a fumigation experiment than in the aqueous phase in vitro. Both in pot tests and in field trials, trans-2-hexenal showed significant efficacy against M. incognita while maintaining excellent plant growth, especially at doses of 1000 and 500 L ha, which were superior to that of abamectin at 180 g ha via hole application treatment but not significantly different from fumigation with 400 kg ha of dazomet. Furthermore, plants treated with 500 L ha trans-2-hexenal had fruit yields 20.2 and 45% greater than the control group. On this basis, trans-2-hexenal may be a potential alternative fumigation agent for controlling M. incognita on tomato crops.

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The application of pesticide microcapsules (MCs) in agriculture is becoming more and more popular. In this study, the effects of different wall materials on the stomach toxicity, contact toxicity, length of efficacy, and photolysis characteristics of pesticide microcapsules were investigated. The results showed that microencapsulation reduced the stomach and contact toxicities of phoxim and prolonged the efficacy of this light-sensitive chemical in the greenhouse test. Neither of the degradation curves for microencapsulated phoxim under ultraviolet light fit a first-order model, although the emulsifiable concentrate (EC) degradation curve fit it well. The phoxim-loaded polyurea microcapsules (PUA-MCs) showed significantly increased UV-resistance ability, stomach toxicity, and contact toxicity compared with the phoxim-loaded urea-formaldehyde microcapsules (UF-MCs). These experiments indicated that it is crucial to select the appropriate wall materials for pesticide microcapsules on the basis of application sites and physicochemical properties of pesticide active ingredients.

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