Insect Management Research Articles

Biofumigation with species of the Brassicaceae family: a review

ABSTRACT: Biofumigation involves the release of volatile biocidal compounds in the soil through the incorporation of certain plants and their residues. Species of the Brassicaceae family are the most widely used plants for biofumigation. These plants contain glucosinolates, which produce compounds, such as isothiocyanates, following enzymatic hydrolysis, with scientifically proven fungicidal effects. The most commonly used brassica species belong to the genera Brassica, Raphanus, Sinapis, and Eruca. In addition to the release of compounds in the soil, complementary mechanisms, such as the supply of organic matter and nutrients, and improvement of the soil structure, also play a role in biofumigation. In the past two decades, several studies on the use of brassica residues in biofumigation have been published, showing promising results in the management of soil pathogens (fungi and oomycetes, nematodes, bacteria, and protozoa), weed seeds, and insects. Usage of new biofumigation compounds has also been validated in recent years, including the development of patented technological products such as liquid formulations and pellets. The objective of this article was to review these new developments, beginning with concepts related to biofumigation, and to discuss the mechanisms of action of compounds involving brassica species and the recommendations on usage. Promising examples of the use of this technique are also presented, further detailing the advances in basic and applied knowledge on the subject.

Determine the Gamma Radiation Technique to Sterilization of Insects from Risk Factor

The sterile insect technique (SIT) is an environment-friendly blighter management technique with application within the area-wide integrated management of key pests, together with the suppression or elimination of introduced populations and therefore the exclusion of recent introductions. Procreative sterility is often evoked by radiation, a convenient and consistent technique that maintains an inexpensive degree of aggressiveness within the discharged insects. The price and effectiveness of an effective program integration of the SIT rely on the balance between sterility and aggressiveness, but it seems that current operational programs with an associate SIT element aren't achieving an associated, applicable balance. In this paper, we will discuss how to improve the sterilization method as well as a simple model and procedure for determining the optimum dose. The work in the gift was focused on an association analysis of the electromagnetic wave technique for insect sterilization as a risk issue. Discharge of enormous numbers of gamma-radiated male flies over the complete island caused concern regarding sterilization as an attainable technique for the dominant insects' public health. Several studies on the sterilization of varied insect vectors of sickness have been conducted since then. The study's goal was to check if electromagnetic waves were an efficient insect management mechanism. Insect sterilization is commonly used to create safe environments for fruit homes, manage blighters, and avoid livestock health issues. The sterilization insect technique entails mass-rearing of the target species, sterilization of the male, and unharnessing in sufficient numbers to equal wild male flies in the natural environment. It's species-specific, with no results for any of the 'non-target' species.

Management of Pest Insects and Plant Diseases in Fruit and Nursery Production with Laser-guided Variable-rate Sprayers

Laser-guided variable-rate intelligent spray technology is anticipated to reduce pesticide use in production of crops and safeguard the environment. However, the ability of this technology to effectively control insect pests and diseases of crops must be validated before it becomes part of integrated pest management programs. Abilities of three different intelligent sprayers were tested to control pest insects and plant diseases at one fruit farm and two ornamental nurseries in Ohio during three consecutive growing seasons. The same sprayers with disabled intelligent functions were used as conventional constant-rate applications for comparisons. Test crops were apple (Malus pumila), peach (Prunus persica), blueberry (Vaccinium sect. Cyanococcus), black raspberry (Rubus occidentalis), crabapple (Malus sp.), maple (Acer sp.), birch (Betula sp.), and dogwood (Cornus florida). There were five insects and six diseases total involved in the investigations in the fruit farm and two nurseries. The field tests showed the intelligent spray applications reduced pesticide and foliar fertilizer use by ≈30% to 65% on average during the 3-year experiments. At the same time, intelligent spray technology was similar or more effective than conventional spray technology when controlling insects and diseases on a variety of crops. These results demonstrated that intelligent spray technology was environmentally friendly and more effective for control of insect and disease pests in fruit farms and ornamental tree nurseries.

The Promise of a Multi-Disciplinary, Mixed-Methods Approach to Inform Insect Pest Management: Evidence From Wyoming Alfalfa

Pest management strategies involve a complex set of considerations, circumstances, and decision-making. Existing research suggests that farmers are reflexive and reflective in their management choices yet continue to employ curative rather than preventative strategies, and opt for chemical over biological solutions. In this piece, we detail work from a two-year, multidisciplinary, mixed-methods study of insect pest management strategies in alfalfa in Wyoming, integrating data from four focus groups, a statewide survey, and biological sampling of production fields. We outline how these different sources of data together contribute to a more complete understanding of the challenges and strategies employed by farmers, and specifically on biological pest control. We applied this approach across alfalfa hay and seed crop systems. Relatively few farmers acknowledged biological control in focus groups or surveys, yet biological exploration yielded abundant parasitism of common pest alfalfa weevil. On the other hand, parasitism of seed alfalfa pestLyguswas far less common and patchy across fields. It is only in integrating quantitative and qualitative, biological and social data that we are able to generate a more complete portrait of the challenges and opportunities of working with farmers to embrace a preventative paradigm. In doing so, we offer insights on possible barriers to the adoption of preventative insect management strategies and provide a case study of integrating social science and biophysical techniques to better understand opportunities to expand biological pest control in cropping systems.

Charakterisierung von Antixenose und Antibiose bei Mais-Genotypen in Bezug auf Dichelops melacanthus Dallas (Hemiptera: Pentatomidae)

Stink bugs are considered limiting pests to important crops worldwide. In Brazil, the green-belly stink bug, Dichelops melacanthus Dallas (Hemiptera: Pentatomidae), has become a key pest to the young phase of corn crop, being a problem especially when it succeeds soybean in the field. Injuries caused by this species vary from holes on new leaves to plant death in severe attacks. The main control technique used to this pest are seed treatment and insecticide spraying. Although both methods show some efficiency, factors as outbreaks in the resistance to insecticides and the different susceptibility existent among stink bugs population, leads to the search of other control strategies. Thus, less harmful tools to the environment and humans are highly desirable. In this sense, resistant plants appear as a valuable alternative for insect management, being compatible with other IPM methods. This study evaluated the resistance of 16 corn genotypes to D. melacanthus in order to characterize antixenosis and/or antibiosis expression. Antixenosis was accessed through preference multi-choice test with 5th instar nymphs. For antibiosis assessment, 60 2nd instar nymphs were confined on seedlings of 13 selected genotypes. Seedlings of IAC 8046, IAC 8390 and SCS 156 Colorado corn genotypes were less infested by D. melacanthus at 24 h after bugs were released indicating antixenosis expression. Genotypes IAC 8390 and JM 2M60 negatively affected some biological parameters of the green belly stink bug, indicating the occurrence of antibiosis. These genotypes can be useful to breeding programs focusing on corn resistance to stink bugs species.

Reemerging Rice Orange Leaf Phytoplasma with Varying Symptoms Expressions and Its Transmission by a New Leafhopper Vector-Nephotettix virescens Distant.

Rice orange leaf phytoplasma (ROLP) belongs to the “Candidatus Phytoplasma asteris” 16SrI-B subgroup, which is solely transmitted by the zigzag-striped leafhopper (Recilia dorsalis Motchulsky) and the green leafhopper (Nephotettix cincticeps Uhler) (Hemiptera: Cicadellidae). Recently, rice plants showing orange leaf discoloration have become ubiquitous in several paddies of two provinces in the Philippines. In total of 98 symptomatic rice plants, 82% (Laguna) and 95% (Mindanao) were ROLP-positive by nested PCR detection. These plants showed more varying symptoms than previously reported. The vector insect R. dorsalis was scarcely present but green paddy leafhopper, N. virescens Distant (Hemiptera: Cicadellidae), was commonly observed in the paddies, thus the ability of N. virescens to transmit ROLP was thoroughly investigated. Newly emerged adult N. virescens, which fed on ROLD-source rice plants, were used to inoculate a susceptible rice seedling and was serially transferred into a new healthy seedling. Resultant positive transmission rates varied from 5.1% to 17.8%. The transmission ability of the insects was generally decreased over time. These findings suggest that N. virescens is an alternative vector of ROLP in the Philippines. Altogether, this study highlighted the increasing importance of ROLD-reemergence in Southeast and East Asia and proved the need for careful management of this alternative vector insect.

Management of flying insects on expressways through an academic-industrial collaboration: evaluation of the effect of light wavelengths and meteorological factors on insect attraction

Insect outbreaks often occur in the absence of natural enemies and in the presence of excess suitable host materials. Outbreaks of gypsy moths are especially problematic in remote areas located in high-latitude regions in Japan because the majority of adults emerge during the short summer season and initiate synchronous mass flight toward artificial lights. The aggregation of moths in public facilities not only is an annoyance to visitors but also permits the establishment of new populations the following year. The aim of this study was to establish a method to reduce the numbers of large moths that are attracted to lights in the rest areas of expressways in Hokkaido based on the results of research on their behavioral ecology and physiology. First, we conducted extensive insect surveys using light traps that emit light at different wavelengths; the traps were set along the expressways in the summers of 2014–2018. The insects attracted to the light were roughly classified into those showing a preference for broadband light wavelengths (from UV-A to green) and short light wavelengths (from UV-A to blue). The former included aquatic insects and winged ants, and the latter included moths and beetles. Next, we analyzed correlations between moth emergence and daily meteorological data. When gypsy moths were abundant during an outbreak, the daily catch of gypsy moths was positively correlated with the highest ambient temperature on the catch day but not with the visibility range, wind speed, or moon phase. In contrast, the daily catch of oak silkmoths did not correlate with any of these parameters. Our results provide guidance for the management of forest insects inhabiting cool-temperate to subarctic regions based on light wavelengths with reference to weather variables.

Dispersal constraints on the potential distribution of cold‐adapted stag beetles (genus Platycerus) in Japan and the implications of climate change

Abstract The effects of climate change on species distribution are typically inferred based on species distribution models (SDMs) that do not account for the dispersal ability of species. Here we investigated the utility of dispersal ability measures in predicting the distribution of 10 Platycerus species in Japan, which are cold‐adapted stag beetles sharing ecological and morphological features. We generated three SDMs based on environmental variables without dispersal constraint and incorporating two alternative dispersal constraint scenarios. We compared these three models with respect to SDM performance and the predicted degree of range overlap between neighbouring species. Using the best models among three SDMs, we predicted range shifts under climate change. Additionally, we characterised environmental differences among species distributional areas. Our results revealed that models incorporating dispersal constraints had better predictive performance. Platycerus delicatulus occupied a largest suitable habitat and P. sue had a narrow range in Japan. Most of Platycerus taxa in 2070 were predicted to lose large portions of present suitable areas. Moreover, environment was confirmed to affect the distribution of the targeted species. Incorporating dispersal ability to better understand the effects of climate change on the species ranges is a crucial step towards developing policies for insect management and conservation of vulnerable species.

Current scenario of RNAi-based hemipteran control.

RNA interference (RNAi) is an homology-dependent gene silencing mechanism that is a feasible and sustainable avenue for the management of hemipteran pests. Commercial implementation of RNAi-based control strategies is impeded by limited knowledge about the mechanism of double-stranded RNA (dsRNA) uptake, the function of core RNAi genes and systemic RNAi mechanisms in hemipteran insects. This review briefly summarizes recent progress in RNAi-based studies aimed to reduce insect populations, viral transmission and insecticide resistance focusing on hemipteran pests. This review explores RNAi-mediated management of hemipteran insects and offers potential solutions, including in silico approaches coupled with laboratory-based toxicity assays to circumvent potential off-target effects against beneficial organisms. We further explore ways to mitigate degradation of dsRNA in the environment and the insect such as stacking and formulation of dsRNA effectors. Finally, we conclude by considering nontransformative RNAi approaches, concatomerization of RNAi sequences and pyramiding RNAi with active constituents to reduce dsRNA production and application cost, and to improve broad-spectrum hemipteran pest control. © 2020 Society of Chemical Industry.

A toxin complex protein from Photorhabdus akhurstii conferred oral insecticidal activity against Galleria mellonella by targeting the midgut epithelium

The nematode-bacterium pair Heterorhabditis indica-Photorhabdus akhurstii is a malleable model system to investigate mutualistic relations. A number of toxins produced by P. akhurstii allow the bacterium to kill the insect host. However, a few of these heterologously expressed toxins are orally active against different insects which possibly caused neglected attention to Photorhabdus toxins compared to Bt (Bacillus thuringiensis). In the current study, a functional subunit of orally active toxin complex (Tc) protein, TcaB (63 kDa), isolated from two strains of P. akhurstii namely IARI-SGHR2 and IARI-SGMS1, was tested for biological activity against Galleria mellonella. A force feeding-based administration of the toxin translated into LD50 values of 45.63–58.90 ng/g which was even lower compared to injection LD50 values (51.48–64.30 ng/g) at 48 h after inoculation. An oral uptake of 500 ng toxin caused extensive gut damage in G. mellonella during 6–24 h incubation period coupled with a gradual disruption of gut integrity leading to escape of TcaB into the hemocoel. This finding was supported by the cytotoxic and immune-stimulatory effect of TcaB in the insect hemocoel at 6–24 h after force feeding. The circulatory hemocyte numbers and cell viability was markedly reduced to 0.66−0.68 × 106 ml−1 and 49–52 %, respectively, in TcaB force fed insect at 24 h, compared to control (2.55 × 106 ml−1; 100 %). The hemolymph phenoloxidase (PO) activity was elevated by 10.2-fold in force fed larvae than control at 24 h. An in silico docking study revealed that TcaB putatively interacts with a number of G. mellonella receptor proteins in order to become a gut-active toxin. Present research reinforces the potential of gut-active Photorhabdus toxins for their inclusion in sustainable insect management tactics and strengthens the existing Bt-dominated management repository.

Review of the direct and indirect effects of warming and drought on scale insect pests of forest systems

AbstractHigher temperatures and drought are key aspects of global change with the potential to alter the distribution and severity of many arthropod pests in forest systems. Scale insects (Hemiptera: Coccoidea) infest many tree species and are among the most important pests of trees in urban and rural forests, plantations and other forest systems. Infestations of native or exotic scale insects can kill or sicken trees with economic and ecosystem-wide consequences. Warming can have direct effects on the life history, fitness and population dynamics of many scale insect species by increasing development rate, survival or fecundity. These direct benefits can increase the geographic distribution of scale insects and their consequences for tree health. Warming and drought can affect scale insects indirectly by altering the quality of their host trees. Additive or interactive effects of warming and drought can change tree quality in such a way that it increases scale insect fitness and population growth. However, the effects are species- and context-dependent with some scale insect species negatively affected by drought-induced changes in tree quality. Warming and drought are often coincident in urban forests and predicted to co-occur in many parts of the world under climate change scenarios. The individual and interactive effects of these factors require further research to inform predictions and management of scale insect pests. Warming also indirectly affects scale insects by altering interactions with natural enemies. This includes changes in natural enemy phenology, community composition and abundance. In addition, warming can alter scale insect phenology or voltinism causing asynchrony with natural enemies or population growth too rapid for natural enemies to suppress. Direct and indirect effects of warming and drought on scale insects can increase the potential for some exotic species to become established and for some native species to become invasive. Unfortunately, much research on scale insects is confined to a few particularly important native or exotic pests which limits our ability to predict the effects of warming on many current or potential pests. More research is required to understand how warming and drought affect scale insects, scale insect management and the forest systems they inhabit.

Effect of gamma irradiation and subsequent cold storage on the development and predatory potential of seven spotted ladybird beetle Coccinella septempunctata Linnaeus (Coleoptera; Coccinellidae) larvae

Seven spot ladybird beetle, (Coccinella septempunctata) is a widely distributed natural enemy of soft-bodied insect pests especially aphids worldwide. Both the adult and larvae of this coccinellid beetle are voracious feeders and serve as a commercially available biological control agent around the globe. Different techniques are adopted to enhance the mass rearing and storage of this natural enemy by taking advantage of its natural ability to withstand under extremely low temperatures and entering diapause under unfavorable low temperature conditions. The key objective of this study was to develop a cost effective technique for enhancing the storage life and predatory potential of the larvae of C. septempunctata through cold storage in conjunction with the use of nuclear techniques, gamma radiations. Results showed that the host eating potential of larvae was enhanced as the cold storage duration was increased. Gamma irradiation further enhanced the feeding potential of larvae that were kept under cold storage. Different irradiation doses also affected the development time of C. septempuntata larvae significantly. Without cold storage, the lower radiation doses (10 and 25 GY) prolonged the developmental time as compared to un-irradiated larvae. Furthermore, the higher dose of radiation (50GY) increased the developmental time after removal from cold storage. This study first time paves the way to use radiation in conjunction with cold storage as an effective technique in implementation of different biological control approaches as a part of any IPM programs

Damage severity of wood-destroying insects according to the Bevan damage classification system in log depots of Northwest Turkey

The aim of the study was to determine damage severity of wood-destroying insects on logs stored in forest depots. The Bevan damage classification (BDC) system, developed in 1987, was utilized to determine damage severity in log depots in 21 locations throughout seven provinces in Turkey. Pheromone traps were placed in those locations at the beginning of April in 2015 and 2016. Furthermore some stored wood within the log depots were checked and split into small pieces to collect insects that damage wood. The BDC system was used for the first time to measure the severity of insect damage in log depots. Twenty-eight families, 104 genera and 123 species were identified in this study. Based on the BDC system, the highest damage was found from the Cerambycidae and Buprestidae families. Arhopalus rusticus was determined as the insect responsible for the highest amount of damage with 8.8% severity rating in the pheromone-trapped insects group. When the stored wood material was considered, Hylotrupes bajulus was found to be the cause of the highest damage. The lowest damage values were among the predator insects (Cleridae, Trogossitidae, Cantharidae) and those feeding on fungi colonized on the wood (Mordellidae, Cerylonidae, Nitidulidae). Some other predator insects of the Tenebrionidae family (Uloma cypraea, Uloma culinaris, Menephilus cylindricus) and Elateridae family (Lacon punctatus, Ampedus sp.) exhibited relatively higher damage severity values since they had built tunnels and made holes in the stored wood material. When the environmental factors were considered, the Buprestidae family exhibited a very strong positive relationship (p < 0.005) with insect frequency distribution (r = 0.922), number of species (r = 0.879) and insect density (r = 0.942). Both families showed the highest number and frequency during July and August, highlighting the importance of insect control and management during these months.

The value of insect management to US maize, soybean and cotton farmers.

Most US maize, soybean and cotton farmers use Bt crops, insecticidal seed treatments, soil-applied insecticides, and foliar sprays to manage insect pests. Given the global economic importance of these crops, we examine farmer benefits of this insecticide use. Using a telephone survey, we document pest management practices and concerns, estimate adoption and farmer perceived values for these practices, and determine factors besides yield and cost that impact adoption and perceived value. Seed-based technologies (Bt seed, seed treatments) dominated insecticide use. Almost 80% of respondents' planted hectares used Bt crops and more than half used seed treatments, while about one-sixth used soil insecticides and one-sixth to one-third used foliar insecticides. Perceived farmer values per treated hectare were greatest for Bt cotton and foliar insecticides in cotton, especially after first bloom. Values for maize and other cotton insecticide uses were greater than for soybean. Aggregating over treated areas, the largest total values for each crop were for seed-based technologies. In addition to yield and cost, farmers showed significant concern for economic risk and human and environmental safety when making pest management decisions. These non-monetary concerns significantly affected the likelihood farmers used these practices and their perceived value. For these crops, seed-based insecticides dominate farmer insecticide use and the value they derive from insecticides. Because seed purchase is months before planting, farmers rely on risk-based integrated pest management to make pest management decisions, weighing both monetary and non-monetary factors when deciding whether the risks are sufficient to justify the use of insecticides. © 2020 Society of Chemical Industry.

The burden of bites and stings management: Experience of an academic hospital in the Kingdom of Saudi Arabia

PurposeThe main aim of this study is to estimate the economic burden and prevalence of bites and stings injuries in Saudi Arabia. MethodsA retrospective, cross-sectional study was conducted at King Saud University Medical City (KSUMC) for all bites and stings cases presented to the Emergency Department (ED) between the period June 2015 and May 2019. ResultsA total of 1328 bites and stings cases were treated in the ED at KSUMC. There were 886 insect bites and stings cases, 376 animal bites, 22 human bites, 34 scorpion stings, and ten snakebites. Most cases were reported in April - June. Females account for 62% of the reported cases, and the mean age was 24 years old. The total management cost of bite and sting cases during the study period was 3.4 million Saudi Riyal (SR). The spending cost of the management of animal bites was the highest as it cost 1,681,920.76 SR, followed by insect's management costing 1,228,623.68 SR. ConclusionBites and stings have a considerable health care burden on our society. Although the vast majority of the cases were not associated with a severe life-threatening condition, many were visit ED and associated with high medical costs. Increased awareness of the hazards of animal-related injuries, especially during spring and summer, where most cases take place may lower its incidence and decrease EDs visits.

Characterization and potential mechanisms of resistance of cucumber genotypes to Bemisia tabaci (Hemiptera: Aleyrodidae)

Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) is a major pest of several agricultural crops, being vector of an extreme number of viruses. The broad variety of host plants, high adaptability and evolution of resistance to insecticides evidence the difficult in the management of B. tabaci in the agriculture system. Host plant resistance is a valuable and sustainable method of insect management. To date, few studies have characterized the resistance of cucumber (Cucumis sativus L.) genotypes to B. tabaci, although this plant is one of the most preferred host of this hemipteran. The objective of this study was to assess the resistance of 60 cucumber genotypes against B. tabaci in greenhouse and laboratory conditions and to characterize the mechanisms of resistance involved based on morphological and physical plant parameters. Initially, 12 genotypes were selected in a screening bioassay. In general, ‘IAC-1214’ expressed high levels of antixenosis to the insect, causing low attractiveness to adults and non-preference for oviposition and colonization. 'Wellington' prolonged the development of the insect and provoked low levels of adult emergence, expressing levels of antibiosis. Antibiosis and/or antixenosis were detected in ‘IAC-1201’, ‘Campeiro’, ‘Japones’, and ‘IAC-1311’, while antixenosis was detected in ‘Kyria’ and ‘IAC-1175’. The density of the trichomes and the color of the leaves are described and discussed here. The selected genotypes present potential application in integrated programs that focus on reducing populations of B. tabaci in the agricultural system and in breeding programs aiming to explore resistant genotypes against the insect.

Coding and Non-coding RNAs: Molecular Basis of Forest-Insect Outbreaks.

Insect population dynamics are closely related to ‘human’ ecological and economic environments, and a central focus of research is outbreaks. However, the lack of molecular-based investigations restricts our understanding of the intrinsic mechanisms responsible for insect outbreaks. In this context, the moth Dendrolimus punctatus Walker can serve as an ideal model species for insect population dynamics research because it undergoes periodic outbreaks. Here, high-throughput whole-transcriptome sequencing was performed using D. punctatus, sampled during latent and outbreak periods, to systemically explore the molecular basis of insect outbreaks and to identify the involved non-coding RNA (ncRNA) regulators, namely microRNAs, long non-coding RNAs, and circular RNAs. Differentially expressed mRNAs of D. punctatus from different outbreak periods were involved in developmental, reproductive, immune, and chemosensory processes; results that were consistent with the physiological differences in D. punctatus during differing outbreak periods. Targets analysis of the non-coding RNAs indicated that long non-coding RNAs could be the primary ncRNA regulators of D. punctatus outbreaks, while circular RNAs mainly regulated synapses and cell junctions. The target genes of differentially expressed microRNAs mainly regulated the metabolic and reproductive pathways during the D. punctatus outbreaks. Developmental, multi-organismal, and reproductive processes, as well as biological adhesion, characterized the competing endogenous RNA network. Chemosensory and immune genes closely related to the outbreak of D. punctatus were further analyzed in detail: from their ncRNA regulators’ analysis, we deduce that both lncRNA and miRNA may play significant roles. This is the first report to examine the molecular basis of coding and non-coding RNAs’ roles in insect outbreaks. The results provide potential biomarkers for control targets in forest insect management, as well as fresh insights into underlying outbreak-related mechanisms, which could be used for improving insect control strategies in the future.

The importance of plant diversity in the ecological management of insects in agroecosystems: a review

The objective of this study is to evaluate the importance of plant diversity in insect management in agroecosystems.The conventional management of agroecosystems is based on monoculture, with exploitation of plant genotypes susceptible to pests and diseases, with intense use of agrochemicals and soil mechanization. The impact on agroecosystem biodiversity by intensifying agronomic practices results in losses of important ecological functions: decomposition, nutrient cycling, predation and parasitism. The potential of plant diversity in the sustainability of agroecosystems is recommended through practices such as intercropping, agroforestry systems, management of cover crops, spontaneous herbs and the use of plants attractive to natural enemies and as pest traps. Farm planning should take into account some level of plant diversification to avoid pest insect outbreaks. Thus, it will be possible to reduce pesticides in conventional system, and reduce the number of interventions with alternative substances in farm in agroecological systems.

Age-Stage, two-sex life table: an introduction to theory, data analysis, and application

The life table is a type of research tool that is frequently used in many studies involving population and community ecology. They are the basis for many comprehensive studies in pest management, pesticide resistance, predator-prey relationships, biological control, mass-rearing and harvesting of insects, plant resistance, etc. Because the morphology, physiology, survival, fecundity, and predation/consumption rate of most arthropods will vary significantly depending on their developmental stage and sex, precise description of stage differentiation and inclusion of both sexes are critical for attaining realistic and accurate life table analyses and correctly evaluating the overall fitness of populations. Since traditional female age-specific life tables ignore the male individuals in a population and are incapable of describing the unique and important feature of stage differentiation (i.e., metamorphosis) that is a defining characteristic of insects and mites, their application to data analysis involving these groups will inevitably result in miscalculations and limit the practical application of these life tables. On the other hand, the age-stage, two-sex life table (hereafter referred to as the two-sex life table whenever appropriate), can precisely delineate stage differentiation and includes both sexes in data analysis, description, and interpretation, and in practical applications. In this review, the problems of female age-specific life tables are examined, followed by a discussion of the advantages of using the two-sex life table. Finally, applications of the two-sex life table in various types of entomological research are discussed and accompanied by examples.

Disinfestation techniques for major cereals: A status report.

Management of stored product insects is a major concern and widely researched topic in the food and grain processing and storage industry. In the scenario of estimated utilization of produces exceeding the production, postharvest losses should be properly controlled to feed the growing population. The prevailing disinfestation techniques are forced to meet regulatory standards and market demands. The resistance developed by insects, environmental concerns, and occupational hazards lead to the vanishing of many chemicals used in insect and pest management programs. Some of the major disinfestation techniques such as the use of chemical fumigants, ozone, irradiation, dielectric heating, extreme temperature treatments, and bio rational approaches are discussed, particularly on the storage of cereal grains and its products, as they contribute to a significant proportion of food consumed worldwide. Newer techniques such as nonthermal plasma and metabolic stress disinfestation and decontamination for stored pest control are developed and evaluated in different parts of the world. The knowledge about the mode of action of these disinfestation techniques is important to avoid the cross-resistance and multiple resistance developed by insects with frequently used techniques. Various alternatives to conventional fumigants are discussed in this review as there is a growing demand for toxic-free, environment-friendly, and, at the same time, efficient techniques.