气候变化对中国农作物虫害发生的影响

基于1961—2010年全国农区527个气象站点气象资料、全国病虫害资料以及农作物种植面积等资料,对全国虫害发生面积与气象因子采用相关分析法,分析了气象要素变化对虫害发生的影响。结果表明:气候变化背景下,年平均温度、平均降水强度分别以0.27℃.10a-1、0.24mm.(d.10a)-1的速度增长,年日照时数以47.40h.10a-1的速度减小;年降水量增长速率为0.14mm.10a-1,但波动较大;虫害发生面积率距平与平均温度、平均降水强度距平呈显著正相关,平均温度、平均降水强度分别每增加1℃、1mm.d-1,虫害发生面积率增加0.648、0.713,虫害发生面积将增加0.96、1.06亿hm2次;虫害发生面积率距平与年日照时数距平呈显著负相关,其每降低100h,虫害发生面积率增加0.40,虫害发生面积将增加0.59亿hm2次;总体上,虫害发生面积率距平与年降水量距平的关系不明显。虫害发生面积率距平与年平均小雨量、微雨量雨日数、小雨量雨日数距平呈显著负相关,3个因子分别每减少1mm、1d、1d,虫害发生面积率增加0.014、0.066、0.052,发生面积将增加0.02、0.10、0.08亿hm2次。     

我国花椒害虫研究进展

危害我国花椒的害虫种类达190余种,隶属于16目82科。文章对我国广泛分布及危害严重的花椒害虫的危害特点、发生规律及防治技术进行综述,将我国花椒害虫分布及危害区分为北部、东部、西南部、华南部4个区域。北部地区的主要害虫包括5目24科30余种,危害严重的害虫为花椒窄吉丁甲、花椒桔啮跳甲、台湾狭天牛等;东部地区的主要害虫包括4目11科20余种,危害严重的害虫为台湾狭天牛、二斑黑绒天牛、吹棉蚧等;西南地区的主要害虫包括5目19科20余种,危害严重的害虫为棉蚜、桑拟轮蚧、花椒伪安瘿蚊等;华南地区的主要害虫包括3目16科20余种,危害严重的害虫为棉蚜、花椒桔啮跳甲、星天牛等。     

Diagnostic molecular markers of six lepidopteran insect pests infesting apples in Korea

Two molecular identification techniques for differentiating six lepidopteran pests infesting apples in Korea are presented. These six species include two internal fruit feeders (Grapholita molesta and Carposina sasakii), two leaf rollers (Adoxophyes sp. and Archips breviplicanus) and two leaf miners (Phyllonorycter ringoniella and Lyonetia prunifoliella). All species occur until near harvest and reduce apple production. A 489 bp fragment of mitochondrial cytochrome oxidase subunit I (COI) was sequenced in these six species. The sequence was used to select species-specific restriction enzyme sites and to design diagnostic polymerase chain reaction (PCR) primers, resulting in the development of restriction fragment length polymorphism (RFLP)-PCR and diagnostic PCR. These methods were reliable and rapid in the identification of these six species.     

Genetic engineering of fungal biocontrol agents to achieve greater efficacy against insect pests

Molecular biology methods have elucidated pathogenic processes in several fungal biocontrol agents including two of the most commonly applied entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana. In this review, we describe how a combination of molecular techniques has: (1) identified and characterized genes involved in infection; (2) manipulated the genes of the pathogen to improve biocontrol performance; and (3) allowed expression of a neurotoxin from the scorpion Androctonus australis. The complete sequencing of four exemplar species of entomopathogenic fungi including B. bassiana and M. anisopliae will be completed in 2010. Coverage of these genomes will help determine the identity, origin, and evolution of traits needed for diverse lifestyles and host switching. Such knowledge combined with the precision and malleability of molecular techniques will allow design of multiple pathogens with different strategies to be used for different ecosystems and avoid the possibility of the host developing resistance.     

我国苹果害虫(螨)的研究与防治:回顾与展望

20世纪后50年尤其是改革开放20年来,我国果业生产发展迅猛,成就举世瞩目。截止1998年全国果园面积863．55万hmz,果品总产量达54529亿kg,居世界之首。在落叶果树中苹果发展最快,1998年为283．8万hm’,产量达194．8亿kg,面积和产量在苹果生产国中均居首位,我国年人均占有苹果已达15kg,超出世界人均水平4kg左右。但若以单位面积产量衡量,我国与水果生产发达国家相比尚有较大差距。1998年我国苹果每667mz产量为405．Ikg,仅及发达国家的1／3－l／5。这在一定程度上反映了我国水果生产管理水平的差距,其中病虫为害是重要因素之一。本…     

Increased temperature variation poses a greater risk to species than climate warming

Increases in the frequency, severity and duration of temperature extremes are anticipated in the near future. Although recent work suggests that changes in temperature variation will have disproportionately greater effects on species than changes to the mean, much of climate change research in ecology has focused on the impacts of mean temperature change. Here, we couple fine-grained climate projections (2050–2059) to thermal performance data from 38 ectothermic invertebrate species and contrast projections with those of a simple model. We show that projections based on mean temperature change alone differ substantially from those incorporating changes to the variation, and to the mean and variation in concert. Although most species show increases in performance at greater mean temperatures, the effect of mean and variance change together yields a range of responses, with temperate species at greatest risk of performance declines. Our work highlights the importance of using fine-grained temporal data to incorporate the full extent of temperature variation when assessing and projecting performance.     

Invasive clonal plant species have a greater root-foraging plasticity than non-invasive ones

Clonality is frequently positively correlated with plant invasiveness, but which aspects of clonality make some clonal species more invasive than others is not known. Due to their spreading growth form, clonal plants are likely to experience spatial heterogeneity in nutrient availability. Plasticity in allocation of biomass to clonal growth organs and roots may allow these plants to forage for high-nutrient patches. We investigated whether this foraging response is stronger in species that have become invasive than in species that have not. We used six confamilial pairs of native European clonal plant species differing in invasion success in the USA. We grew all species in large pots under homogeneous or heterogeneous nutrient conditions in a greenhouse, and compared their nutrient-foraging response and performance. Neither invasive nor non-invasive species showed significant foraging responses to heterogeneity in clonal growth organ biomass or in aboveground biomass of clonal offspring. Invasive species had, however, a greater positive foraging response in terms of root and belowground biomass than non-invasive species. Invasive species also produced more total biomass. Our results suggest that the ability for strong root foraging is among the characteristics promoting invasiveness in clonal plants.     

Predicting the effects of climate change on natural enemies of agricultural pests

Climate change can have diverse effects on natural enemies of pest species. Here we review these effects and their likely impacts on pest control. The fitness of natural enemies can be altered in response to changes in herbivore quality and size induced by temperature and CO₂ effects on plants. The susceptibility of herbivores to predation and parasitism could be decreased through the production of additional plant foliage or altered timing of herbivore life cycles in response to plant phenological changes. The effectiveness of natural enemies in controlling pests will decrease if pest distributions shift into regions outside the distribution of their natural enemies, although a new community of enemies might then provide some level of control. As well as being affected by climate through host plants and associated herbivores, the abundance and activity of natural enemies will be altered through adaptive management strategies adopted by farmers to cope with climate change. These strategies may lead to a mismatch between pests and enemies in space and time, decreasing their effectiveness for biocontrol. Because of the diverse and often indirect effects of climate change on natural enemies, predictions will be difficult unless there is a good understanding of the way environmental effects impact on tritrophic interactions. In addition, evolutionary changes in both hosts and natural enemies might have unexpected consequences on levels of biocontrol exerted by enemies. We consider interactions between the pest light brown apple moth and its natural enemies to illustrate the type of data that needs to be collected to make useful predictions.     

华北棉区夏播棉田害虫发生特点分析

分析和比较了华北棉区夏季播种与春季播种的棉田主要害虫（棉铃虫与棉蚜）的发生特点,探讨了它们的管理对策。     

Female spontaneously hypertensive rats have greater renal anti-inflammatory T lymphocyte infiltration than males

T cells contribute to hypertension in male experimental models; data in females is lacking even though women are more likely to develop immune disorders. The goal of this study was to determine whether immune cells contribute to hypertension in female spontaneously hypertensive rats (SHR) and define the T cell profile in whole blood and kidneys of male and female SHR. We hypothesized that inflammatory cells contribute to hypertension in female SHR; however, male SHR have a higher blood pressure so we hypothesize they will have a heightened inflammatory profile. The lymphocyte inhibitor mycophenolate mofetil (MMF) was administered in a dose-dependent manner to SHR. At the highest dose (50 mg·kg(-1)·day(-1)), blood pressure was significantly decreased in both sexes, yet the percent decrease in blood pressure was greater in females (female: 12 ± 1%; males: 7 ± 1%, P = 0.01). Circulating and renal T cell profiles were defined using analytical flow cytometry. Female SHR had more circulating CD3(+), CD4(+), and pro-inflammatory CD3(+)CD4(+)RORγ(+) Th17 cells, whereas males had more immune-suppressive CD3(+)CD4(+)Foxp3(+) T regulatory cells. In the kidney, females had greater numbers of CD8(+) and T regulatory cells than males, whereas males had greater CD4(+) and Th17 cell infiltration. MMF decreased circulating and renal T cells in both sexes (P < 0.0001), although the effect of MMF on T cell subtypes was sex specific with females having greater sensitivity to MMF-induced decreases in lymphocytes. In conclusion, there is a lymphocyte contribution to the maintenance of hypertension in the female SHR and sex of the animal impacts the T cell profile.     

Movement of insect pests in agricultural landscapes

Insect pests continue to exact a high toll on agricultural production, in spite of intense agrochemical input. The movement of insect pests from one place to another underlies their abundance and distribution in space and time, hence, ultimately, the extent of the inflicted crop damage. An improved understanding of dispersal mechanisms assists the deployment of sustainable pest management practices. Here, we review the latest advances in the study of the dispersal of herbivore insect pests in contemporary agro‐ecosystems. We address the factors triggering dispersal in typical agricultural landscapes, the contribution of agro‐ecosystem design and management to dispersal patterns, and the wider implications of natural and human‐mediated dispersal. Integrating practical knowledge with evolutionary theory holds the potential to improve predictions on how insect pests respond to present and future challenges imposed by changes of climate and land use.     

Potential invasion of China by exotic insect pests associated with tree seeds

A total of 39 insect species, mostly seed chalcids in the genus Megastigmus (Hymenoptera), but also midges (Diptera), are listed as potential seed-borne invaders of Chinese conifers. Although the number of native seed insects per conifer genus does not differ between China and other biogeographical regions, there are significantly fewer seed insects associated with each conifer genus in China than potential invaders. The eventual success of the invaders is likely to depend on the presence of native Chinese conifers that are congeneric with the original host, or on the presence of the original host as an exotic. When a substantial entomofauna is already associated with cones, competition for seed resources may limit the potential impact of invaders because seed insects are usually the last organisms to colonize the cone. A survey of 26 fir species, both native and introduced to Europe, showed that overall seed infestation by five species of exotic chalcids is negatively correlated to levels of damage by native insects, except on the original hosts of the chalcids. Similar patterns are hypothesized for native firs, spruces, Douglas firs, and larches in China. Uncontrolled importation of seeds and nuts of broad-leaved trees could also facilitate the introduction of seed chalcids, seed bruchids, tortricid moths and nut weevils into China. Only six species of seed chalcids are present in China, out of the 72 known to attack broad-leaved seeds over the world.     

mRNAs have greater negative folding free energies than shuffled or codon choice randomized sequences

An examination of 51 mRNA sequences in GenBank has revealed that calculated mRNA folding is more stable than expected by chance. Free energy minimization calculations of native mRNA sequences are more negative than randomized mRNA sequences with the same base composition and length. Randomization of the coding region of genes yields folding free energies of less negative magnitude than the original native mRNA sequence. Randomization of codon choice, while still preserving original base composition, also results in less stable mRNAs. This suggests that a bias in the selection of codons favors the potential formation of mRNA structures which contribute to folding stability.     

我国柑桔害虫的研究现状

柑桔是我国南方最重要的果树之一。改革开放以来，柑桔生产的迅速发展对繁荣农村经济，增加农民收入，满足城乡人民的生活需求发挥了重要作用。据国家统计局发表的资料，1998年全国柑桔种植面积发展到127万hmz，总产量达85．9亿kg。但由于柑桔属多年生常绿果树，原产于中国，种植地区气候温和，雨量充沛，因此在柑桔生长发育过程中遭受多种害虫为害。据忡国果树病虫志》（第二版户已载，我国柑桔害虫有2门14目106科865种。在这些害虫中不少属于客居性或偶然发生、为害很轻的种类；有的属于与其他果树或作物共有的种类；只有一部分属柑桔的主…     

Variable effects of climate change on six species of North American birds

Many recent studies have shown that birds are advancing their laying date in response to long-term increases in spring temperatures. These studies have been conducted primarily in Europe and at local scales. If climate change is a large-scale phenomenon, then we should see responses at larger scales and in other regions. We examined the effects of long-term temperature change on the laying dates and clutch sizes of six ecologically diverse species of North American birds using 50 years of nest record data. As predicted, laying dates for most (four of six) species were earlier when spring temperatures were warmer. Over the long-term, laying dates advanced over time for two species (red-winged blackbirds, Agelaius phoeniceus and eastern bluebirds, Sialia sialis). Laying date of song sparrows (Melospiza melodia) also advanced with increasing temperature when the analysis was restricted to eastern populations. Neither laying date nor clutch sizes changed significantly over time in the remaining species (American coot, Fulica americana, killdeer, Charadrius vociferous, and American robin, Turdus migratorius), an unsurprising result given the lack of increase in temperatures over time at nest locations of these species. This study indicates that the relationship between climate change and breeding in birds is variable within and among species. In large-scale analyses of North American birds, four of seven species have shown advances in laying dates with increasing temperature (including song sparrows in the east). These variable responses within and among species highlight the need for more detailed studies across large spatial scales.     

烟叶贮存期害虫的控制技术

烟叶在贮存期中易受虫害 ,烟叶受害后损失在 2 %～ 3%。因而对其防治必须高度重视 ,采用综合性的控制对策能收到较好的防治效果。     

Field tests with insecticides and insect growth regulators to control insect pests of cowpea and its effects on certain beneficial insects

A small‐plot tests were conducted on cowpea, Vigna ungiculata (L.) Walp, to determine the effectiveness of 14 selected insecticides representing four insecticide classes (organophosphates, carbamates, pyrethroids, and insect growth regulators, IGRs), and four insecticide/IGR mixtures on cowpea insect pests and its effects on certain beneficial insects. By day 3 after treatement, the insecticides phenthoate, isoxathion, cyanophos, carbaryl, and cypermethrin used at sub‐recommended rates reduced the leafhopper, Empoasca spp., populations by >83% than those in the control. On that day, all insecticide treatments significantly reduced the cowpea aphid, Aphis craccivora, numbers below that of the control. The prothiofos, isoxathion, pirimicarb, and fenpropathrin treatments provided continuing control to both leafhoppers and aphids through day 21 after spraying. It seems that most insecticide treatments were not effective in whitefly, Bemisia tabaci, control. The best control of the whitefly immatures was obtained by day 3 after spraying in plots received thiodicarb (76%) and fenpropathrin (60%). All selected insecticides and rates used had very low residual effect against B. tabaci immatures. By day 3 posttreatment, the carbaryl (2.02 kg/ha) caused completely protection for cowpea pods frMw blue pea butterfly, Lampides boeticus, larvae. The IGRs, flufenoxuron and Dowco‐439, applied alone and those applied in mixtures with insecticides, carbaryl/teflubenzuron, chlorpyrifos/XRD‐473, and methomyl/ flufenoxuron, exhibited satisfactory control (>81%) to butterfly larvae on day 7 posttreatment. All treatments did not exhibit a considerable residual activity against L. boeticus larvae through 2–3 weeks followed spray. Most insecticides applied at the higher rates used significantly reduced the numbers of limabean pod borer, Etiella zinckenella, larvae found in cowpea pods collected on day 7 after application. The IGRs, flufenoxuron and Dowco‐439, applied alone, at 0.119 kg/ha, or in mixtures, methomyl/flufenoxuron (0.167 kg/ha) and chlorpyrifos/Dowco‐439 (0.911 kg/ha) caused >73% control of E. zinckenella larvae through day 21 posttreatment. The best control of cowpea weevil, Callosobru‐chus spp., adults (>83%), on day 3 after spraying, was obtained in treatments of cyanophos (1.19 kg/ha), prothiofos (1.43 kg/ha), flufenoxuron (0.119 kg/ha), and chlorpyrifos/Dowco‐439 (0.911 kg/ha). The IGR flufenoxuron applied alone or in mixture, methomyl/flufenoxuron (0.164 kg/ ha) exhibited satisfactory residual activity against Callosobruchus adults through day 21 posttreatment. Percentage seed damage by the larvae of cowpea weevils was significantly lower in most treatments than that of control. Populations of insect predators found in all treated plots were extremely reduced than those found in untreated plots. By day 21 after spraying, the IGRs flufenoxuron, XRD‐473, and Dowco‐439, applied at the low rate of 0.071 kg/ha, seemed to be less effect against insect predators than other insecticides used.