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Pheromone binding proteins (PBPs) are thought to play key roles in insect sex pheromone recognition; however, there is little in vivo evidence to support this viewpoint in comparison to abundant biochemical data in vitro. In the present study, two noctuid PBP genes HarmPBP1 and HarmPBP2 of the serious agricultural pest, Helicoverpa armigera were selected to be knocked down by RNA interference, and then the changes in electrophysiological and behavioral responses of male mutants to their major sex pheromone component (Z)-11-hexadecenal (Z11-16:Ald) were recorded. There were no significant electrophysiological or behavioral changes of tested male moths in response to Z11-16:Ald when either single PBP gene was knocked down. However, decreased sensitivity of male moths in response to Z11-16:Ald was observed when both HarmPBP1 and HarmPBP2 genes were silenced. These results reveal that both HarmPBP1 and HarmPBP2 are required for the recognition of the main sex pheromone component Z11-16:Ald in H. armigera. Furthermore, these findings may help clarify physiological roles of moth PBPs in the sex pheromone recognition pathway, which in turn could facilitate pest control by exploring sex pheromone blocking agents.

Odorant binding proteins (OBPs) and chemosensory proteins (CSPs) play important roles in transporting semiochemicals through the sensillar lymph to olfactory receptors in insect antennae. In the present study, twenty OBPs and three CSPs were identified from the antennal transcriptome of Microplitis mediator. Ten OBPs (MmedOBP11–20) and two CSPs (MmedCSP2–3) were newly identified. The expression patterns of these new genes in olfactory and non-olfactory tissues were investigated by real-time quantitative PCR (qPCR) measurement. The results indicated that MmedOBP14, MmedOBP18, MmedCSP2 and MmedCSP3 were primarily expressed in antennae suggesting potential olfactory roles in M. mediator. However, other genes including MmedOBP11–13, 15–17, 19–20 appeared to be expressed at higher levels in body parts than in antennae. Focusing on the functional characterization of MmedCSP3, immunocytochemistry and fluorescent competitive binding assays were conducted indoors. It was found that MmedCSP3 was specifically located in the sensillum lymph of olfactory sensilla basiconca type 2. The recombinant MmedCSP3 could bind several types of host insects odors and plant volatiles. Interestingly, three sex pheromone components of Noctuidae insects, cis-11-hexadecenyl aldehyde (Z11-16: Ald), cis-11-hexadecanol (Z11-16: OH), and trans-11-tetradecenyl acetate (E11-14: Ac), showed high binding affinities (Ki = 17.24–18.77 μM). The MmedCSP3 may be involved in locating host insects. Our data provide a base for further investigating the physiological roles of OBPs and CSPs in M. mediator, and extend the function of MmedCSP3 in chemoreception of M. mediator.

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Plant nitrogen (N)-phosphorus (P) stoichiometry is associated with important ecological processes. However, N-P stoichiometry in soil and plants and adaptive mechanisms of plants to infertile soils in the soil erosion areas remain unclear. We selected 15 plots with Masson pine forest of varying stand ages in typical subtropical soil erosion areas of Southern China. The total nitrogen (TN) and total phosphorus (TP) concentrations in green leaves of Masson pine forest (9.2 and 0.61 g/kg) were significantly lower than the national averages in China (18.6 and 1.21 g/ kg). The N:P ratio (TN:TP) of green leaves (15.1:1) was higher than the national (14.4:1) and the global levels (11.8:1 or 11.0:1). Forest soil TN, TP concentrations (0.41 and 0.14 g/kg) were lower than the national averages. The high N:P ratio of green leaves and low soil TP, AP concentrations indicated that P was important in limiting Masson pine forest growth, especially for forests with stand age less than 10 years. Leaf TN, TP resorption efficiencies of Masson pine forests were 26.5 and 64.9 %, and TP in senesced leaves of Masson pine with different stand ages was completely resorbed, suggesting that Masson pine was effective at adapting to nutrient-poor soils. Differences in leaf N-P stoichiometry among different stand ages indicated that nutrient demand varied with Masson pine forest growth stages. Changes in forest soil N-P stoichiometry suggested that Masson pine forest afforestation could greatly improve the soil quality in the eroded lands. However, the significant improvement would take at least a 30-year-long period.

To give a up‐to‐date review of the present status of dust storm (hereafter DS) researches over China‐Mongolia Areas (CMA), first, the three stages of China DS researches in the last 20 years are reviewed, then the main advances in dust aerosol observations, DS climatology, the circulation patterns of DS outbreak and dust transport, DS activity changes in the past five decades and their causes, as well as some problems to be solved are presented in this paper. It shows that: (1) The DS over CMA originates mainly from both the Northwest China (NWC) and South‐and NW‐Mongolia areas. With the intensifying of the dusty weathers, surface total suspended particulates (TSP) of dust will increase in geometric series at the rate of triples. (2) There exist seven DS high frequence regions in CMA, they are Tarim Basin, Gansu Corridor, Mid‐ and West‐Inner Mongolia, and Hunshandake sand region in China and Dalanzadgad and Zamin Uud in Mongolia. Most of DS events occur between 13:00 to 20:00 Beijing Time (BT) of springs. (3) There are briefly two kinds of DS outbreak circulation patterns in CMA, i.e., the low pressure plus cold front, and the low cold front plus meso‐scale system. Certainly, they are the combinations of the different lows and cold fronts for east‐, mid‐ and west‐ regimes of CMA. The former makes up the most of them; the latter, a few percent only, but is one of the most important disaster weathers to forecast. The dust transport downwind depends mainly on the circulation on lower‐levels. (4) In the past five decades the DS activities over the whole CMA changed in a wavy way, first gradually increased from 1950's to 1970's, got its peak frequency in 1970's; then gradually decreased from 1980's to 1990's; still then increased suddenly in the years 2000~2002 and decreased abruptly in the years 2003~2005. Also their changes in the each regime of CMA are a little different. The main factors which cause the DS interdecadal changes may relate to the interdecadal changes of East Asia atmospheric circulation, not the desertification condition. (5) Finally three aspects which need to further study are given.

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