应用生态工程技术控制水稻害虫对水生昆虫数量的影响

【目的】随着水稻病虫害绿色防控技术的不断发展,希望应用生态工程控制害虫技术取得较大进展。【方法】对稻田水生昆虫成虫的种群动态进行了连续3年的系统调查,以探明生态工程防控技术对水生昆虫的影响。【结果】实施生态工程防控技术稻田中的水生捕食性昆虫豆娘的数量显著高于农民自防田,其他水生捕食性昆虫和中性昆虫等数量也有类似的结果,同时,靠近田埂的稻田区域豆娘和水生中性昆虫的种群数量也显著高于稻田中间区域。【结论】说明通过实施生态工程控害技术可以有效提高稻田水生捕食性昆虫及中性昆虫种群数量,这对提高水稻生长后期的天敌控害作用有重要的意义。     

Multiple effects of two drivers of agricultural change,labour shortage and water scarcity,on rice pest profiles in tropical Asia

The effects of shortage of agricultural labour, represented by direct-seeding technologies replacing transplanting, and of water scarcity, represented by limited water supply, on rice pests (pathogens, weeds, insects) were studied. The analysis was based on a field characterisation data set covering six sites in tropical Asia and several cropping seasons. Two-way ANOVAs and MANOVA were, respectively, used to test the effects of the two factors on individual rice pest injuries, and on the profile of injuries that an individual rice crop experiences over a cropping season. Fourteen injuries were considered, which individually were significantly (P < 0.05) influenced by crop establishment (nine injuries), by water management (11 injuries), or their interaction (nine injuries). Multiple analysis of variance indicated that rice injury profiles, regionally, are altered by both factors. The results suggested that injuries caused by some pests would be enhanced (e.g., brown spot, planthoppers) or reduced (e.g., stem rot, sheath blight, rice whorl maggot) by crop establishment shifting from transplanting to direct-seeding. Water shortages, proxied in our data by poor water management, would favour some injuries (e.g., sheath rot, brown spot, neck blast, whiteheads) or suppress others (e.g., stem rot, sheath blight). Very strong increases in weed infestation were observed with both direct-seeding and poor water management. The results are discussed with respect to pest management in rice.     

Use of the response of two growth stages of cowpea to different population densities of the coreid bug, Clavigralla tomentosicollis (Stål.) to determine action threshold levels

The effects of increasing the population density of the cowpea coreid, Clavigralla tomentosicollis Stål., up to a maximum of 32 pairs of insects per cage, infested on cowpea at either early flowering or mid pod-fill, were studied in potted plants and field cages. Overall, the results show that increasing insect density resulted in a corresponding increase in damage to the crop (measured as abscission of fruiting bodies and as damage to pods and seeds). Yield reduction was approximately proportional to the bug population when low, with highly significant correlation coefficients. Damage to the crop and yield reduction were more drastic when infestation was made during flowering as opposed to infestation at podding; although there was some compensation of damage to fruiting bodies during the former growth phase, this was not sustained with increasing pest density. Suggested pest densities at which control measures should be initiated are two insects (fourth instar and over) per 10 plants at flowering and four insects at podding. Further studies on damage thresholds in multiple pest scenarios are suggested.     

Vegetation management and biological control in agroecosystems

The application of diversity/stability considerations in theoretical ecology has led to the emergence of testable hypotheses with implications for biological control and agroecosystem management. The object of applied research in this area has been to achiece predictably stable pest populations (below an economic threshold level) in crop systems. The exacerbation of most insect-pest problems has been associated with increases in crop monocultures at the expense of the natural vegetation, thereby decreasing local habitat diversity. This can seriously affect the abundance and efficiency of natural enemies, which depend on habitat complexity for sources of alternate prey/hosts, pollen and nectar, shelter, nesting and overwintering sites. Plant diversification of agroecosystems can result in increased environmental opportunities for natural enemies and, consequently, improved biological pest control. Agronomically, there are several ways to design plsnt-diverse cropping systems. One way is by manipulating the vegetation of field margins, and managing the species composition and density of plants in ditchbanks, hedgerows, windbreaks and other types of shelter belts. Within-field plant diversity can be manipulated by designing polycultures of various temporal and spatial crop arrangements. The effects of some of these systems on the dynamics of insect populations are discussed, as well as the effects of cover-crop management on pest insects in orchards. Another way to enrich the vegetational structure of cropping systems is through weed management. Weed diversity in the form of weed borders, alternate rows, or by providing weeds in certain periods of the crop growth can have a major impact on insect dynamics.     

Inhibition of reproduction of Acanthoscelides obtectus Say (Coleoptera), a kidney bean (Phaseolus vulgaris) bruchid, by aromatic essential oils

Acanthoscelides obtectus Say (Coleoptera, Bruchidae), is a cosmopolitan pest that damages its host plant, the kidney bean (Phaseolus vulgaris L.) in the field and during storage. The use of aromatic essential oils from Labiatae, Umbelliferae and Lauraceae was investigated. In addition to a fumigant toxic effect on adult insects, inhibition of reproduction through ovicidal and larvicidal effects was also observed. These actions might be combined to improve the management of this bruchid: essential oils of Rosmarinus officinalis, Thymus vulgaris, T. serpyllum, Ocimum basilicum and Cinnamomum verum were very effective and completely controlled the biological development of this insect.     

白裙赭夜蛾的研究

白裙赭夜蛾是莲雾的主要害虫，幼虫为害叶片呈缺刻状，严重发生时可将叶片吃光。此虫一年发生１２代，一代需时２７－４４ｄ。发生严重时可喷９０％敌百虫８００倍液防治。     

Farmers’ knowledge and perceptions of pests in agroforestry with particular reference to Alnus species in Kabale district, Uganda

Ugandan farmers were interviewed in order to investigate their knowledge, perceptions and ability to manage pests in agroforestry generally and on Alnus species particularly. Farmers’ ability to recognise pest problems on Alnus species was significantly influenced by their length of experience in cultivating the species, but not their age, sex or formal education. Most farmers (77%) were aware of pest problems on Alnus species. However, identification of pest problems was based largely on damage type rather than causal agents. Whereas farmers had good knowledge of vertebrate pests of Alnus, insects and diseases that infest the tree species were unknown to most farmers. Apis mellifera damage on Alnus was the most frequently described damage, but its cause was either unknown or misdiagnosed. Most farmers did not control insect and disease infestations on Alnus because they did not know the causal agents and/or appropriate control measures. Farmers were generally more knowledgeable on insect and disease infestations on crops than on multipurpose tree species (MPTS) and most of them (98%) perceived that crops suffer more damage from such pests than do MPTS. However, farmers’ ability to manage insect pests and diseases seemed weak on both crops and MPTS. Most farmers suggested the use of pesticides to combat pests, but they mentioned only one insecticide, permethrin and one fungicide, mancozeb. More alarming were the suggestions by a few farmers on the use of mancozeb against aphids, and permethrin to combat crop wilt and dieback. Farmers need to be educated about diagnosis, basic ecology and management strategies for both crop and tree pests to ensure sustainable pest control in agroforestry.     

Management of insect pests in celery and potato crops by pneumatic removal

Over the course of 4 years, five sets of trials were run in celery and potato crops to evaluate the efficacy of a field-scale vacuum (FSV) unit for use in insect pest management. The unit was designed to dislodge insects by blowing air from lateral vents onto the plants while simultaneously vacuuming from above. Efficacy was evaluated by field observations, yellow sticky traps and hand vacuum sampling before and after the FSV. All insects evaluated were effectively removed by the vacuum unit; typically, population reductions of 50–75% were achieved with whiteflies, leafhoppers, and aphids. In some trials, reductions were achieved that lasted from week to week. Additionally, agromyzid leafminers were significantly reduced in number, but population reductions were temporary because of their strong flying ability.     

Integrated pest management in field vegetable crops in northern Europe — with focus on two key pests

Improvements in (1) insecticide application, (2) supervised control, and (3) pest forecasting systems have each helped to reduce considerably the amounts of insecticides required to control fly, caterpillar and aphid infestations in vegetable crops in northern Europe. By growing plants that are partially resistant to certain major pests, it is now possible to apply even less insecticide than the dose recommended for the crop. In crops where only small amounts of insecticides are applied, natural predators should prevent large increases in pest insect populations and natural parasitoids should reduce the numbers of pest insects entering subsequent generations. The possible impact of introducing transgenic plants and the use of physical (crop covers), cultural (crop rotation, undersowing) and microbial (e.g. fungi, bacteria and nematodes) methods of control are also discussed. The withdrawal of certain insecticides, as a result of environmental and commercial pressures, means that some crops may soon be without appropriate insecticides for controlling one or more of the major pest species. Whether such systems will be sustainable, remains to be seen.     

Behavioral Effects and Retention of Protein Immunomarkers on Plum Curculio Conotrachelus nenuphar (Coleoptera: Curculionidae)

Protein immunomarking can be used to track the dispersal of insects in the field or identify plant–insect interactions. By marking insects with known proteins and recapturing them, their movement or host use can be quantified with Enzyme Linked Immunosorbent Assay (ELISA). Before using this technique, retention and behavioral effects of these markers should be evaluated to ensure that the insect’s natural behaviors are conserved. Here, we tested the effects of protein markers on the plum curculio, Conotrachelus nenuphar (Coleoptera: Curculionidae) using two different application methods. This weevil is native to North American and a pest of tree fruit and blueberry in the United States and causes damage resulting in near complete crop loss if left untreated. We tested the effects of marking adult C. nenuphar with two inexpensive food-based immunoprotein markers, bovine casein (cow’s milk) and chicken albumin (egg whites) on climbing distance (total cm), lateral movement (total cm), and lateral movement speed (cm/s), as well as retention time of protein immunomarkers. Neither protein immunomarker affected C. nenuphar movement or climbing, although females climbed significantly greater distances than males. ELISA assays detected 37.5–56.2% of milk protein and 56.2–59.3% of egg on the insect 7 d after application depending on application method. Our findings indicate that food-based protein immunomarkers can be used in future studies to test C. nenuphar movement within host plants without impacting behavior. The use of protein immunomarking will allow studies that will lead to behaviorally based management tactics.     

Non-targeted insecticidal stress on the Neotropical brown stink bug Euschistus heros

Lethal and sublethal insecticide effects on non-targeted pest species are frequently neglected but have potential consequences for pest management and secondary pest outbreaks. Here, the lethal and demographic effects of four soybean insecticides (chlorantraniliprole, deltamethrin, pyriproxyfen, and spinosad, which are used against caterpillars, whiteflies, and green stink bugs) on the brown stink bug Euschistus heros (F.), the main stink bug species currently attacking Neotropical soybean fields, were assessed. Deltamethrin exhibited drastic acute mortality in adult females of E. heros with a median lethal time (LT₅₀) of 0.6 days, whereas pyriproxyfen treated females exhibited a survival similar to that of water-treated insects (LT₅₀ of 89 and 67 days, respectively). Chlorantraniliprole and spinosad-treated females exhibited intermediate survival with a TL₅₀ of 54 and 47 days, respectively. Further scrutiny of the three most selective insecticides (i.e., chlorantraniliprole, pyriproxyfen, and spinosad) using age-structured matrices to assess the demographic impact of these compounds under earlier exposure indicated that both pyriproxyfen and spinosad significantly reduced the population growth of the pest species by compromising the survival of eggs (<17% hatching) and 1st nymphs (LT₅₀ of 3 and 2 days, respectively) and fertility; these results were unlike those obtained for chlorantraniliprole- and water-treated controls, which exhibited less than 50% mortality during development. However, chlorantraniliprole significantly compromised the fertility of adult insects (>50% reduction compared with water-treated insects) to a greater extent than pyriproxyfen and spinosad, but without impairing insect population growth as much. Therefore, although pyriproxyfen and spinosad, besides deltamethrin, are not used to target the Neotropical brown stink bug, these insecticides adversely affected this pest species at the dose recommended for application on the label, thereby preventing its outbreak under such conditions.     

Sustainable Management of Rice Insect Pests by Non-Chemical-Insecticide Technologies in China

Chemical pesticides play crucial roles in the management of crop diseases and pests. However, excessive and irrational use of pesticides has become a major concern and obstacle to sustainable agriculture. As a result, the quality and security of agricultural products are reduced, and the ecological and environmental integrities are threatened. Recently, environment-friendly pest management measures have been introduced and adopted to manage rice insect pests and reduce the use of insecticides. This paper reviewed the advancements in development and application of non-chemical technologies for insect pest management during rice production in China.     

导入外源DNA大豆后代的抗虫性鉴定与筛选

大豆食心虫（Leguwinivora glycinivorella)和大豆蚜虫（Aphid glycines)是东北大豆生产的主要虫害。为拓宽资源的利用，创造抗虫大豆种质，用花粉管通道技术向大豆品种吉20、吉25、吉27、吉30等导入皂角（Gleditisia japonica)、鹰嘴豆（Cicer arietinum)和农家早期品种DNA，对从后代中选出的变异系进行了多年抗虫性鉴定和筛选，得到了抗虫品系4个。本文报告了抗虫鉴定筛选结果。     

Research Progress on Oviposition-Related Genes in Insects

Oviposition-related genes have remained a consistent focus of insect molecular biology. Previous research has gradually clarified our mechanistic understanding of oviposition-related genes, including those related to oviposition-gland-related genes, oogenesis-related genes, oviposition-site-selection-related genes, and genes related to ovulation and hatching. Moreover, some of this research has revealed how the expression of single oviposition-related genes affects the expression of related genes, and more importantly, how individual node genes function to link the expression of upstream and downstream genes. However, the research to date is not sufficient to completely explain the overall interactions among the genes of the insect oviposition system. Through a literature review of a large number of studies, this review provides references for future research on oviposition-related genes in insects and the use of RNAi or CRISPR/Cas9 technology to verify the functions of oviposition-related genes and to prevent and control harmful insects.     

Physical and cultural methods for the management of soil-borne pathogens

There is an increasing interest in using physical methods and cultural practices (CP) in disease control as alternatives to pesticides for the management of soil-borne pathogens. These can be used alone or as components of pest management programs. In this regard, there are three categories of CP: (a) CP for regular purposes which can also be used for disease control, e.g. irrigation; (b) CP which are used solely or mainly for pest control, e.g. sanitation; (c) CP which can be used for both agricultural purposes and pest control, e.g. crop rotation. The basic principles of CP for pest control are (a) any potential control method may be considered, providing that it is environmentally, technologically and economically feasible; (b) pesticide usage is minimized by combining with other non-chemical or chemical methods; (c) diseases that are difficult to control or that involve problematic pesticides, e.g. methyl bromide, should be prioritized; (d) economic aspects are taken into consideration. Physical methods include heating the soil or propagation material, irradiation, etc. CP for pest control can be used before, at or after planting. They include crop rotation, fallow, flooding, deep ploughing, flaming, soil solarization — which involves a combination of physical and biological processes, adjusting planting date, irrigation, fertilization, compost, weed control, herbicide application, sanitation, tillage and others.     

Sex Specificity in Innate Immunity of Insect Larvae

The innate immunity of insects has been widely studied. Although the effect of sex on insect immunity has been extensively discussed, differences in immunity between the sexes of larvae insects remain largely unstudied. Studying larval sex differences in immunity may provide valuable information about the mechanisms underlying the insect immune system, which, in turn, can be valuable for the development and improvement of pest management. Here we compared the antibacterial activity in both the midgut tissue and cell-free hemolymph of Lymantria dispar L. (Lepidoptera: Erebidae) females and males at the larval stage without and after a challenge by entomopathogenic bacterium Bacillus thuringiensis Berliner. We also evaluated the sex-specific mortality of L. dispar induced by B. thuringiensis infection. We find that antibacterial activity in the midgut is activated by infection, but only in females. Thus, sex differences in immunity can have important effects even before sexual differentiation at adulthood.     

Characterizing the Feeding Injury Caused by Phylloscelis rubra (Hemiptera: Dictyopharidae) to Cranberries

Due to changes in pest management practices, farmers’ reports of severe feeding injury to cranberries, Vaccinium macrocarpon Aiton Ericales: Ericaceae, caused by the cranberry toad-bug, Phylloscelis rubra Ball, have increased in recent years in New Jersey (United States). Currently, however, limited information is available on the effects of P. rubra feeding or density of individuals needed to cause injury to cranberry vines and fruit. In 2015‒2017, we conducted studies to characterize injury to cranberry at a range of P. rubra densities by using cages in a screen-house and field, to establish a correlation between P. rubra density and crop injury in an open field experiment, and to measure the effects of P. rubra injury on the nutritional content (i.e., amounts of macro- and microelements) of cranberry vines. Phylloscelis rubra feeding on cranberry vines produced typical injury symptoms at relatively low densities (i.e., 2 individuals per vine in field cages or <10 individuals per sweep net sample in open fields), which included discolored (yellowish or reddish) or dead (brown) vines. This vine injury could lead to reductions in fruit mass and total fruit number. However, P. rubra injury to cranberry vines did not alter their nutritional composition. In general, this study highlights the ability of P. rubra to cause substantial injury to cranberry vines even when population densities were relatively low, which could result in declines in fruit production (quality and quantity). Therefore, infestations by P. rubra in cranberries must be considered when making pest management decisions in regions where this insect is present.     

Monte Carlo simulation method for forecasting the timing of pest insect attacks

The timing of attack by pest insects can vary greatly both from region to region and from year to year because the rates at which insects complete their life cycles depend mainly on temperature. In addition, variation between individual insects in their rate of development can lead to a spread of activity. A simulation method, based on rates of insect development, has been produced for forecasting the timing of attack by pest insects. Variability is incorporated using the ‘same-shape property’ which implies that the coefficient of variation of the rate of insect development is independent of temperature. The method is feasible because it uses a fixed number of individuals from one generation to the next and simulates the timing of events rather than the population dynamics of the insects. The method is sufficiently flexible to allow insect resting phases to occur at the appropriate instant for each individual. Its effectiveness in predicting the behaviour of the cabbage root fly (Delia radicum), the carrot fly (Psila rosae), the bronzed blossom beetle (Meligethes aeneus) and the large narcissus fly (Merodon equestris) is demonstrated for one site in one season. To be of practical use, the method has been designed to use standard meteorological data. Estimation of soil temperatures at 6 cm and the derivation of equations for estimating diurnal variation are described in two appendices. The basis of the method is the integration of a temperature-dependent rate function over time. A third appendix describes a quicker and more accurate method of integration than that usually employed in pest forecasting work.     

Factors determining adoption of integrated pest management by vegetable growers in Nakhon Ratchasima Province,Thailand

Widespread use of highly toxic pesticides primarily for agricultural purpose has generated increasing concerns about the negative impact of pesticides on human health and the environment. Integrated pest management (IPM) usually seeks to minimize the use of pesticides and can be utilized to solve pest problems while minimizing risks to people and the environment. A total of 220 vegetable farmers in Nakhon Ratchasima Province of Thailand was interviewed with the objective of investigating the factors determining their adoption or non-adoption of IPM practices. The findings demonstrated that farmers had different uncompromising reasons for determining the use of IPM for their insect pest management. Higher costs of insecticides (91%), adverse effects of insecticides on human health and the environment (80%), and a greater risk of insect pests developing resistance to insecticides (28%) were the primary reasons for the adoption of IPM by vegetable growers in the study area. The reasons for the rejection of IPM practice were unsuitability of IPM for a large farm (52%), implementation difficulties (80%) and a greater belief in synthetic insecticides and their efficacy for target pest control (39%). A comparison between the IPM and the non-IPM farmers showed a significant difference (P < 0.01) in farmers' knowledge of pest management, which influenced IPM adoption or non-adoption. The IPM farmers had greater knowledge about identifying natural enemies and their beneficial role in controlling insect pests, about plant extracts and their efficacy in controlling insect pests and about sticky traps and their efficacy in monitoring natural enemies and controlling insect pests. For example, 24% of IPM farmers had knowledge of natural enemies whereas it was only 4% for the non-IPM farmers. A logistic regression model was fitted which showed that lower cost of pest management, better knowledge on IPM after training and availability of extension services were the factors which influenced farmers' adoption of IPM practice. The non-IPM farmers rejected adoption of IPM due to the common belief that natural enemies would not be effective in controlling insect pests and yields of vegetables would not be increased by practicing IPM.     

Sublethal effects of spinosad and emamectin benzoate on larval development and reproductive activities of the cabbage moth,Mamestra brassicae L. (Lepidoptera: Noctuidae)

Lepidopteran insect pest management has relied heavily on synthetic chemical pesticides, but their efficiency is declining as a result of emerging insecticide resistance. Recently biopesticides have become the most promising products employed in pest management strategies. We investigated the sublethal effects of two bioinsecticides, spinosad and emamectin benzoate, on larval and pupal development, and reproductive activity including calling behaviour, pheromone production, fecundity and fertility of the cabbage moth, Mamestra brassicae. To assess sublethal effects, second instar larvae were fed with 0.005, 0.05, or 0.5 μg a.i. spinosad/g diet or 0.00005, 0.0005, or 0.005 μg a.i. emamectin benzoate/g diet. Both bioinsecticides significantly increased larval and pupal development time and negatively affected reproductive activity of M. brassicae. The calling activity of females decreased very significantly in the highest sublethal concentration of spinosad and in all treatments by emamectin benzoate. The results suggest that, both spinosad and emamectin benzoate are promising alternatives to conventional insecticides for the control of M. brassicae if successfully introduced into Integrated Pest Management (IPM) programs.