Showing papers in "Entomological Research in 2009"
TL;DR: The sustainability of these species is fundamental; therefore, it is necessary to take certain measures for species conservation.
Abstract: Environmental cycles and human factors have altered ecosystems throughout the world. Natural resources have acquired high value because they are important to life and the survival of human beings. Among these resources are edible insects. They have many important features and, to date, up to 2086 species are consumed by 3071 ethnic groups. Rural people, who primarily search, gather, fix, commercialize and store this important natural resource, do not exterminate them. This is because rural people exploit only the central part of the insects' population curves. Nonetheless, some species are overexploited. Anthropo-entomophagy (eating of insects by humans) constitutes a major source of nutrition and these foods are eaten in 130 countries, with the African and American continents being the most entomophagous until now. It exists in protocultures (care is given to the edible insect species) and formal cultures, such as in Mexico, which date back to prehisphanic times. According to anthropologists the “saving gene theory” is based on insect ingestion, which, since the Paleolithic era, has given human beings reproductive success. The evolution of anthropo-entomophagy has been achieved in many ways, from the point of view of collection, fixing, marketing and consumption, and for the insects' organoleptical qualities. The sustainability of these species is fundamental; therefore, it is necessary to take certain measures for species conservation. In Mexico, more than 100 species of edible insects have been tested for their sustainability over 500 years, from the Spanish conquest to the present.
255 citations
TL;DR: The situation on continents such as Africa, Asia, and Central and South America has some parallels to Australia in that there are two forces in operation: the sustainable traditional use of edible insects and the “westernization” of these societies leading to a movement away from entomophagy.
Abstract: With an increasing human population and environmental degradation, the world faces a major problem in providing adequate animal based proteins. Many traditional societies have used or still use insects as a protein source, while westernized societies are reluctant to use insects, despite being the major consumers of animal proteins. We now need to consider insects as a source of food for humans in a manner that acknowledges both the role of entomophagy in indigenous societies and the need for westernized societies to reduce the size of their environmental footprint with regard to food production. The situation on continents such as Africa, Asia, and Central and South America has some parallels to Australia in that there are two forces in operation: the sustainable traditional use of edible insects and the “westernization” of these societies leading to a movement away from entomophagy. However, the potential to reach a compromise is greater in these continents because entomophagy is already accepted. The major challenges will be establishing sustainable production systems that include food safety and security as well as environmental protection. Whether this will happen or not will depend upon: (i) a major change in attitude in westernized societies towards entomophagy; (ii) pressure to conserve remaining habitats in a sustainable manner; (iii) economic impetus to develop food production systems that include insects; and (iv) an acknowledgement that achieving adequate nutrition on a global basis will involve different diets in much of the developed world.
214 citations
TL;DR: The common edible insects and their use in China are reviewed and more than 50 species have been analyzed for their nutritive elements and nutritional value.
Abstract: This paper reviews the common edible insects and their use in China. One-hundred and seventy-eight insect species from 96 genera, 53 families and 11 orders are commonly eaten in China. Preparation of edible insects includes frying, braising, stewing, stewing after frying, boiling and roasting. The insect forms eaten range from eggs to adults; however, in restaurants most are larvae and pupae. More than 50 species have been analyzed for their nutritive elements and nutritional value and these data are reviewed here. Insect health foods sold in the Chinese market are also briefly discussed.
143 citations
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TL;DR: The case studies presented here describe such insect‐related customs as the continuation of the traditional practice of insect eating in Japan, Southeast Asia and Southern Africa as the socio‐cultural implications of people's preferences regarding edible insects.
Abstract: Insects are an important natural resource, both for self-sufficiency and as commercial food products in many parts of the world. The use of edible insects reflects regional preferences and socio-cultural significance, which can be described in terms of regional differences. This study describes some edible insects in three regions: Japan, Southeast Asia and Southern Africa, and focuses on systems of traditional practices as the socio-cultural implications of people's preferences regarding edible insects. The case studies presented here describe such insect-related customs as the continuation of the traditional practice of insect eating in Japan, Southeast Asia and Southern Africa. These case studies describe the uniqueness or special characteristics of the custom, and the significance of its existence in the social sphere. Edible insects are regarded as cultural resources reflecting a rich biodiversity. They represent an alternative source of natural food resources in remote or mountainous areas. People who eat insects have established a broad variety of methods for collecting and cooking the rich diversity of edible insect species that are available. However, increases in demand could lead to competition and overexploitation, resulting in the future decline of these resources. In areas affected by overdevelopment, insect habitats are also likely to decline. It is necessary to raise people's awareness of the importance of the use of insects for food in order to ensure that insects are used in a sustainable manner, and to promote their proper use and conservation.
84 citations
TL;DR: Suggestions are made towards the uses of medicinal insects and it is proposed that insects will be a main resource for the future discovery of new drugs.
Abstract: The research and utilization of medicinal insects in China is introduced briefly in this paper. Medicinal insects have been used to treat human diseases from ancient times. There are approximately 300 medicinal insects species distributed in 70 genera, 63 families and 14 orders at present. An estimated 1700 traditional Chinese medicine prescriptions include medicinal insects or insect-derived crude drugs. Many insect-derived compounds have been studied and show efficient therapeutic functions. Techniques for mass rearing and cultivation of medicinal insects have been developed in order to have sufficient quantities of medicinal insects. Suggestions are made towards the uses of medicinal insects and it is proposed that insects will be a main resource for the future discovery of new drugs.
64 citations
TL;DR: Adult mosquito surveillance was conducted during 2005 at 22 US military installations and two training sites located in six provinces in the Republic of Korea and New Jersey to determine threshold levels to initiate pesticide applications based on trap indices.
Abstract: Adult mosquito surveillance was conducted during 2002 at 30 US military installations and training sites located in six provinces in the Republic of Korea (ROK). Adult mosquitoes were collected in New Jersey and dry ice -baited New Jersey light traps from 1 May through 15 October. Mosquito surveillance was conducted to determine threshold levels to initiate pesticide applications and identify malaria infection rates at selected Army installations and training sites. A total of 100,617 adults [82,410 (81.9%) females and 18,207 (18.1%) males] comprising 17 species and 7 genera were collected during 2002. The most common species collected were Culex tritaeniorhynchus Giles (49.5%), Anopheles sinensis Wiedemann (30.9%), Culex pipiens Coquillett(11.8%) and Aedes vexans nipponii (Theobald) (7.1%). Trap indices (TIs) varied widely for species over their range, due in part, to geographical distribution and degree of association with urban communities. Anopheles sinensis were collected at the same level while Culex tritaeniorhynchus increased by 27.2% in 2001, due in part to very high populations of Culex tritaeniorhynchus at Gunsan Air Base. The weekly population densities for some species were variable for each of the years, apparently as a result of variable annual weather conditions. None of Anopheles sp. assayed for plasmodium vivax (Pv) malaria infections by Enzyme Linked Immunosorbent Assay (ELISA) were positive.
40 citations
TL;DR: Attention has recently been paid to a synergistic approach to combating insecticide resistance and the introduction of synergists in pest control could have great benefit both economically and ecologically.
Abstract: Advances in the application of microbial-based technology in insect pest management assist us to counter problems created by the application of chemical pesticides. These are mainly strong environmental effects, resistance development and high costs. Among the microbial pesticides, fungal pesticides are now preferred as they are target specific, ecofriendly, lacking in toxic residue and are economical. Being numerous with great diversification, entomopathogenic fungi therefore have great potential to control a large variety of insect pests. Fungi are applied directly in form of spores, mycelia or blastospores or by their metabolites (mycotoxins). Both approaches have very promising roles in insect pest management. However, there are three main obstacles in the development of fungal pesticides: (i) scant production of mycotoxins; (ii) carcinogenic mycotoxicosis in non-target organisms; and (iii) slow effectiveness. Therefore, to eliminate these problems, attention has recently been paid to a synergistic approach to combating insecticide resistance. Next to synergism, genetic manipulation is also used to enhance the pathogenicity and virulence of fungal insecticides. However, the key risk associated with the release of recombinant microorganisms into the environment is that the novel organism may have unforeseen undesirable characteristics. Therefore, the introduction of synergists in pest control could have great benefit both economically and ecologically. An ideal synergistic approach is the mixing of more than two accelerating components together, i.e. tripartite or multiple synergism to enhance effectiveness. Thus, synergistic approaches have a bright future and require further research and financial support.
32 citations
TL;DR: The smoke toxicity of T. asiatica against Ae.
Abstract: Investigations were made to evaluate the larvicidal activity and smoke repellent potential of Toddalia asiatica (L.) and Aegle marmelos at different concentrations (20, 40, 60, 80 and 100 p.p.m.) against first to fourth instar larvae and pupae of Aedes aegypti (L.). The LC50 of A. marmelos and T. asiatica against first instars was 50.960 and 47.893 p.p.m., respectively; against second instars, 52.979 and 50.922; third instars, 56.653 and 54.461; and fourth instars, 60.778 and 61.278. The LC50 and LC90 for A. marmelos and T. asiatica against pupae were 56.634 and 112.992, and 53.64 and 116.22 p.p.m., respectively. The smoke toxicity of T. asiatica against Ae. aegypti was greater than that of A. marmelos. Smoke-exposed gravid females oviposited fewer eggs when compared to those that were not exposed to smoke. Smoke-exposed females hatched a lower percentage of eggs compared to unexposed females.
28 citations
TL;DR: Integrated pest management strategies aimed at reducing pesticide application, such as rotating the conventional insecticides having low resistance with newly developed synthetic insecticides and conserving natural enemies, are recommended.
Abstract: Susceptibility of field populations of Helicoverpa armigera (Lepidoptera: Noctuidae) from Punjab, Pakistan to selected insecticides was evaluated using the leaf dip method. The resistance factors varied between populations. The general trends were low to moderate resistance to endosulfan; very low to low resistance to chlorpyrifos and profenofos; very low resistance to spinosad, indoxacarb and thiodicarb; moderate to high resistance to bifenthrin; high to very high resistance to cypermethrin; and very high resistance to lambda-cyhalothrin. Integrated pest management strategies aimed at reducing pesticide application, such as rotating the conventional insecticides having low resistance with newly developed synthetic insecticides and conserving natural enemies, are recommended.
22 citations
TL;DR: Global meteorological changes have caused an expansion of the active period, leading to the mosquito's possibility of being a vector of disease increasing, resulting in the spread of dengue fever.
Abstract: Adults and immatures of Aedes mosquito populations were collected at temperatures between 40 and 44°C (summer), while larvae were collected at 0°C (winter). Major mosquito activities were observed from February to mid-December at various collection sites that yielded high populations of Aedes spp. from May to September, and high populations of Culex spp. and Anopheles spp. from March to September. In June to July, mosquito activity was suspended because the relative humidity was high (70%); a result of the monsoon rains. In August, with temperature ranging from 38 to 42°C, the populations of Culex, Anopheles and Aedes began to increase (36.8, 32.1 and 26.3%, respectively). Population estimates (through standard prototype Centers for Disease Control (CDC) and Biogents (BG)-sentinel) and species composition of Aedes in forest habitats indicated a rapid increase in the populations of Ae. albopictus (52.3%), Ae. aegypti (19.1%) and Ae. vittatus (28.5%) following the rainy season in July. Areas positive for Ae. albopictus had identical population levels and distribution ranges of Ae. vittatus, however, there were no Ae. aegypti in Ae. albopictus areas from August to September. The population level, seasonal distribution, habitat and areas of adult activity marked by global positioning system (GPS) coordinates are being used for reference and for species composition data of Anopheles spp. (2), Culex spp. (10) and Aedes spp. (5) in addition to associated temperature, relative humidity and physico-chemical factors of larval habitat. Global meteorological changes have caused an expansion of the active period, leading to the mosquito's possibility of being a vector of disease increasing, resulting in the spread of dengue fever.
21 citations
TL;DR: Six different diets were investigated in the experiment, and the results showed that 20% rice straw with 80% oakwood sawdust was the best diet for larval growth of this beetle.
Abstract: The white-spotted flower chafer, Protaetia brevitarsis seulensis (Kolbe), is used as an important source of medicinal properties, such as anti-cancer activity and prevention of liver-related diseases, in Korea. To use this insect species without endangering wild populations, a mass rearing technique is needed. The present study was carried out to determine whether different diets can affect the larval growth of P. brevitarsis seulensis. Six different diets were investigated in the experiment, and the results showed that 20% rice straw with 80% oakwood sawdust was the best diet for larval growth of this beetle.
TL;DR: Under colder and drier environments in dispersed montane localities, abdominal melanization and desiccation resistance significantly increased (1.5–1.9 fold) along altitude, suggesting that changes in body melanization impact fitness‐related traits in montane populations of Drosophila immigrans.
Abstract: We investigated eight populations of Drosophila immigrans from low to high montane localities (600–2202 m) for altitudinal variations in abdominal melanization and fitness-related traits (desiccation resistance, copulation duration, and fecundity). On the basis of common garden experiments, persistence between-population differences at 21°C suggests that observed variations in fitness-related traits have a genetic basis. Parent–offspring regression analyses showed higher heritability (h2= 0.77) for melanization patterns on all the abdominal tergites. All the traits showed significantly higher repeatability across generations. Under colder and drier environments in dispersed montane localities, abdominal melanization and desiccation resistance significantly increased (1.5–1.9 fold) along altitude. Thus, there are correlated effects of abdominal melanization on desiccation resistance. Genetic correlations, based on family means, were significantly high between abdominal melanization and other fitness traits. Furthermore, darker flies along increasing altitude resulted in a 35–40% increase in copulation duration as well as fecundity. There are significantly positive correlations of abdominal melanization with copulation duration as well as fecundity on the basis of within- as well as between-population variations. Such observations are in agreement with the thermal budget hypothesis. Present data suggest that changes in body melanization impact fitness-related traits in montane populations of Drosophila immigrans.
TL;DR: Fungus treatment of Cryptolestes ferrugineus and Oryzaephilus surinamensis eggs had no effect, and T. castaneum eggs demonstrated that the fungus penetrates and infects them.
Abstract: Beauveria bassiana (Balsamo) Vuillemin was tested under maximum challenge conditions with an estimated dose of 1.1 × 10 5 conidia/mm 2 for its effects on eggs of four of the major beetle pests of stored grain and grain products. When ambient relative humidity (RH) was 92%, hatch of fungus-treated Rhyzopertha dominica (Fabricius) eggs was 13% versus 58% for control eggs, and hatch of treated Tribolium castaneum (Herbst) was 17% versus 51% for controls. There was no fungus effect at RH of 48 and 73%. Fungus treatment of Cryptolestes ferrugineus (Stephens) and Oryzaephilus surinamensis (Linnaeus) eggs had no effect. Sectioned T. castaneum eggs demonstrated that the fungus penetrates and infects them.
TL;DR: In this article, α-Amyrin acetate, the n-hexane fraction of acetone extract from the leaves of Catharanthus roseus, was evaluated for its larvicidal, pupicidal and fecundity effects as well as insect growth regulator activity against the malaria vector Anopheles stephensi Liston.
Abstract: Vector control is a serious concern in developing countries. Over the past two decades, phytochemicals have received progressively more attention as insecticide alternatives, and they have recently become the focus in the concept of integrated vector control. α-Amyrin acetate, the n-hexane fraction of acetone extract from the leaves of Catharanthus roseus, was evaluated for its larvicidal, pupicidal and fecundity effects as well as insect growth regulator activity against the malaria vector Anopheles stephensi Liston. The highest concentration of 1 p.p.m. produced 100% mortality in first to second instars and 94% mortality in third and fourth instars. In addition, the duration of larval instars and the total developmental time were prolonged, while female longevity and fecundity were markedly decreased. The suppression of pupation and adult emergence was probably due to its action similar to juvenile hormone analogs in combination with growth regulator activity and toxicity, which reduced the overall performance of the malaria vector An. stephensi.
TL;DR: It is clear from the current study that thermoregulation and Ca2+ ion can positively affect the hemocyte numbers especially plasmatocytes and granulocytes, nodule formation and phenoloxidase activity in E. integriceps.
Abstract: Environmental conditions in addition to divalent cations may affect the interactions between pathogens and insects. Elucidation of factors which modulate insect immune responses could be a significant part of investigations in this area. In this study, adults of Eurygaster integriceps, as the destructive pest of wheat, were kept at different temperatures in addition to injection with different concentrations of Ca 2+ to find the effect on cellular immune reactions against Beauveria bassiana. Results showed that total and differentiate hemocyte numbers, nodule formation and phenoloxidase activity increased with elevation of temperature so that the higher values were obtained at 30 and 40°C at various intervals. Higher concentrations of Ca 2+ ion (5 mM) caused an increase in plasmatocyte length and width especially after 60 min. Similar results were observed for nodule formation and phenoloxidase activity of E. integriceps adults after injection by B. bassiana spores and phenoloxidase activity. It is clear from the current study that thermoregulation and Ca 2+ ion can positively affect the hemocyte numbers especially plasmatocytes and granulocytes, nodule formation and phenoloxidase activity in E. integriceps. The understanding of modulators of the insect immune response may directly influence novel approaches to obtain safe and effective biological control agents.
TL;DR: A study to integrate different control measures against Helicoverpa armigera (Hübner) on chickpea to minimize the use of hazardous insecticides and develop an eco‐friendly management program found the integration of weeding, hand picking and Steward proved to be the most effective in reducing the larval population.
Abstract: A study was carried out at the University of Arid Agriculture, Rawalpindi, Pakistan to integrate different control measures against Helicoverpa armigera (Hubner) on chickpea, to minimize the use of hazardous insecticides and develop an eco-friendly management program. Cultural (weeding), mechanical (hand picking), biological (release of Trichogramma chilonis), microbial (spraying of Bacillus thruingiensis) and chemical (Steward) control practices were applied three times at 10 day intervals individually and also in various combinations. The application of Steward proved most effective when applied alone, with 0.41 larvae/plant, pod infestation of 9.31% and the highest grain yield (1203.66 g/plot); however, the integration of weeding, hand picking and Steward proved to be the most effective in reducing the larval population (0.12 larvae/plant) with minimum pod infestation (5.45%) on variety CM-2000, which resulted in the maximum grain yield (1260.33 g/plot). The cost–benefit ratio in the treatment where Steward was applied alone was 1:2.20, and it was 1:3.53 where weeding and hand picking practices were integrated.
TL;DR: This study is the first report of German cockroach resistance to permethrin in Indonesia, and the findings can be used in formulating potential strategies forcockroach resistance management.
Abstract: The German cockroach, Blattella germanica, is a major and the most common pest in public areas in Indonesia. Although intensive control measures have been carried out to control the populations of this pest, results have been far from successful, which is believed to be because of its resistance to insecticides. A standard World Health Organization (WHO) glass jar test was carried out to determine the resistance level of this insect to pyrethroid insecticides, the most commonly used insecticides for cockroach control in Indonesia. A susceptible S1 strain collected from Tembagapura Papua was compared with four strains collected from Bandung, West Java: strain S2, from a local restaurant; strain S3, from the Bandung train station; and strains S4 and S5, from two different hotels. All strains showed low resistance to the pyrethroid, except the S5 strain, which had a Resistance Ratio (RR)50 of 95 for permethrin. The addition of piperonyl butoxide (PBO) suggests that the detoxifying enzyme mixed function oxidases (MFO) played an important role in the development of resistance to permethrin in the S5 strain, suggested by the high Synergist Ratio (SR) of 70.4. However, the low level of resistance to cypermethrin was not affected by PBO, suggesting that other mechanisms of pyrethroid resistance are involved. Our study is the first report of German cockroach resistance to permethrin in Indonesia, and the findings can be used in formulating potential strategies for cockroach resistance management.
TL;DR: The susceptibility of Blattella germanica in the Republic of Korea (ROK) to insecticides was evaluated under laboratory conditions using 12 insecticides currently used by the local public health centers and/or pest control operators in the ROK.
Abstract: The susceptibility of Blattella germanica (L.) in the Republic of Korea (ROK) to insecticides was evaluated under laboratory conditions using 12 insecticides currently used by the local public health centers and/or pest control operators in the ROK. The insecticides included seven pyrethroids and five organophosphates. Based on their LD50 values, the order of susceptibility of B. germanica adults to the insecticides was chlorpyrifos-methyl, profenofos and chlorpyrifos with values of 0.07, 0.29 and 0.88 µg/♀, respectively. The least susceptibility was obtained with tetramethrin at LD50 of 7.39 µg/♀. In the comparative resistance test, the resistance ratios (RR) of 12 insecticides were compared to each other using field-collected B. germanica adults in Seoul between 1993 and 2007. Blattella germanica demonstrated higher RRs to pyrethroids such as λ-cyhalothrin, and low RRs among the organophosphates. Among the pyrethroids, λ-cyhalothrin had the highest RRs of 111- and 129-fold differences at LD50 and LD90 values, respectively. Among the organophosphates, profenofos was observed to have the highest RRs of 4- and 15-fold differences at LD50 and LD90 values, respectively. However, there were no significant differences in susceptibility to tetramethrin, chlorpyrifos and fenitrothion. Blattella germanica was more susceptible to pyridafenthion showing a 0.7-fold difference in a resistance ratio (RRLD50= LD50 value of 2007/LD50 value of 1993). Resistance ratio of tetramethrin was low, but susceptibility was also not high.
TL;DR: Careful and planned restoration practices to increase the diversity of foraging resources, microenvironment diversity and potential nesting areas for wild bees are needed to improve the ability of the Satoyama system to support more diverse and abundant wild bee populations.
Abstract: Satoyama is a traditional land management system in Japan that emphasizes the importance of a harmonious relationship between humans and their environment. It has been in a state of abandonment and destruction since the late 1960s. In 2000, the Japanese government initiated a new environment policy encouraging the use of Satoyama in biodiversity reservation areas. Before the initiation of active restoration works, an assessment of the potential of the Satoyama system is needed. To assess this potential, a study that focused on the foraging ecology of wild bees in a small abandoned Satoyama terraced paddy was carried out from June to October 2003. A total of 372 foraging bees belonging to 35 species in nine families was collected: two species of social bee ( Apis cerana and Bombus diversus ) and two of solitary bee ( Lasioglossum japonicum and Lasioglossum ohei ) dominated. The foraging activities of wild bees were highly influenced by the requirement of food for the colony and the active time of solitary bees. In the study, most wild bees showed a strong preference for abundant flowering plant species that produced a large number of flowers ( Achyranthes japonica and Polygonum thunbergii ). The results showed that an abandoned Satoyama system was an agricultural system that benefited pollinating bees. Careful and planned restoration practices to increase the diversity of foraging resources, microenvironment diversity and potential nesting areas for wild bees are needed to improve the ability of the Satoyama system to support more diverse and abundant wild bee populations.
TL;DR: The cusp catastrophe model suggests that RWA population growth is intrinsically catastrophic, and dramatic jumps from one state to another might occur even if the temperature and plant‐growth stage change smoothly.
Abstract: Many insect field populations, especially aphids, often exhibit irregular and even catastrophic fluctuations. The objective of the present study is to explore whether or not the population intrinsic rates of growth (rm) obtained under laboratory conditions can shed some light on the irregular changes of insect field populations. We propose to use the catastrophe theory, one of the earliest nonlinear dynamics theories, to answer the question. To collect the necessary data, we conducted a laboratory experiment to investigate population growth of the Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), in growth chambers. The experiment was designed as the factorial combinations of five temperatures and five host plant-growth stages (25 treatments in total): 1800 newly born RWA nymphs arranged in the 25 treatments (each treatment with 72 repetitions) were observed for their development, reproduction and survival through their entire lifetimes. After obtaining the population intrinsic rates of growth (rm) from the experimental data under various environmental conditions, we built a cusp catastrophe model for RWA population growth by utilizing rm as the system state variable, and temperature and host plant-growth stage as control variables. The cusp catastrophe model suggests that RWA population growth is intrinsically catastrophic, and dramatic jumps from one state to another might occur even if the temperature and plant-growth stage change smoothly. Other basic behaviors of the cusp catastrophe model, such as catastrophic jumps, hystersis and divergence, are also expected in RWA populations. These results suggest that the answer to the previously proposed question should be “yes”.
TL;DR: Resistance was not observed when the discriminating doses of emamectin and spinosad were applied on field‐collected populations of H. armigera from two intensive cotton growing areas, Coimbatore and Madurai, India.
Abstract: Acute toxicity studies of emamectin and spinosad against Helicoverpa armigera revealed that the pest is highly susceptible to both the insecticides. The median lethal dose (LD50) of emamectin is 3.86 × 10−3 µg per larva. The median lethal concentrations (LC50) of emamectin and spinosad were found to be 0.09 and 2.94 ppm, respectively. The discriminating doses were fixed based on the LC95 of the susceptible population of H. armigera as 0.80 ppm for emamectin and 10 ppm for spinosad. Resistance was not observed when the discriminating doses of emamectin and spinosad were applied on field-collected populations of H. armigera from two intensive cotton growing areas, Coimbatore and Madurai, India.
TL;DR: A comparative study of male and female genitalia was carried out in thirty‐seven Libyan species representing twenty genera of the family Acrididae to discover their significance in order to make the identification of genera and species, together with other generic characters, more perfect and convenient.
Abstract: A comparative study of male and female genitalia was carried out in thirty-seven Libyan species representing twenty genera of the family Acrididae. An attempt has been made to describe and illustrate the different structures, namely, epiphallus, aedeagus, subgenital plate, supra-anal plate and cerci of the male, and spermatheca, ovipositor, subgenital plate, supra-anal plate and cerci of the female, in Acridids, with an aim to discover their significance in order to make the identification of genera and species, together with other generic characters, more perfect and convenient. Distinct family characters are shield or bridge-shaped condition of epiphallus; presence or absence of dorso-lateral appendices, oval sclerites and lophi on epiphallus; divided, undivided or flexured condition of aedeagus; presence or absence of gonopore process on aedeagus; condition of apical and pre-apical diverticula of spermatheca; presence or absence of glandular pouches of Cornstock and Kellog on female subgenital plate; and rudimentary or well developed condition of egg-guide. Stable characters for separating the subfamilies are taken to be presence or absence of ancorae on epiphallus, long or short condition of aedeagal sclerites; elongate, slender or short and broad condition of ovipositor valves: presence or absence of Jannone's organs and setae on posterior margin of female subgenital plate; and shape of diverticula of spermatheca. Useful generic characters are shape of male subgenital plate, supra-anal plate and cerci, broad or narrow condition of bridge, presence or absence of branch of bridge connecting lophi with bridge of epiphallus; mono-, bi- or tri-lobate condition of lophi of epiphallus, length and upcurved or downcurved condition of apical valve of aedeagus, shape of posterior margin of female subgenital plate, presence of setae on the whole posterior margin or confined to lateral margins only; and toothed, tuberculate or smooth condition of ovipositor valves, length of the lateral apodeme in relation to the dorsal valves. Specific characters are shape of egg-guide of female subgenital plate, shape of ovipositor valves and apical tips, shape of male supra-anal plate and cerci, size of anterior and posterior lobes of lophi of epiphallus, size and shape of ancorae, shape of apical valves of aedeagus; and size of apical and pre-apical diverticula and presence of protuberance on pre-apical diverticulum.
TL;DR: Results will assist in the formulation of an appropriate culture medium for optimal carotenoid production of R. mucilaginosa HP for commercial use.
Abstract: Yeasts have been studied because of their production of a pigment known as carotenoid with potential application in food and feed supplements. A carotenoid-producing yeast was isolated from the larvae of Pieris rapae, named HP. The strain HP was identified as Rhodotorula mucilaginosa classified by its carbohydrate fermentation pattern and physiological tests. Rhodotorula mucilaginosa HP produces several exogenous enzymes: alkaline phosphatase, esterase, leucine arylamidase, valine arylamidase, acid phosphatase and β-glucosidase. Using response surface methodology, selected medium components (yeast extract, malt extract, peptone, glucose) were tested to find the optimum conditions for carotenoid production and the growth of R. mucilaginosa HP. Central composite design was used to control the concentrations of medium components. Peptone and glucose had the largest effects on carotenoid production and cell growth of R. mucilaginosa HP, respectively. The estimated optimal growth conditions of R. mucilaginosa HP were: yeast extract 3.23%, malt extract 2.84%, peptone 6.99% and glucose 12.86%. The estimated optimal conditions for carotenoid production were: yeast extract 2.17%, malt extract 2.11%, peptone 5.79% and glucose 12.46%. These results will assist in the formulation of an appropriate culture medium for optimal carotenoid production of R. mucilaginosa HP for commercial use.
TL;DR: Indoxacarb, an oxadiazine insecticide, was evaluated for its effectiveness against Helicoverpa armigera collected from selected locations in India using a log‐dose probit (LDP) bioassay against third instars collected from cotton fields near Akola, India.
Abstract: Indoxacarb, an oxadiazine insecticide, was evaluated for its effectiveness against Helicoverpa armigera collected from selected locations in India. Determination of Indoxacarb efficacy was done using a log-dose probit (LDP) bioassay against third instars collected from cotton (Gossypium arborium) fields near Akola, India. Monthly levels of toxicity of Indoxacarb were determined from July 2005 to March 2007. The maximum tolerance level of Indoxacarb was reported for the Amaravati strain (5.09 p.p.m.) and the minimum tolerance level for the Fatehbad strain (0.22 p.p.m.). Seasonal monitoring of Indoxacarb toxicity revealed an increased trend in tolerance from July 2005 to February 2006, which decreased from March 2006. The LC50 of Indoxacarb was 2.71 p.p.m. in July 2005 and 17.14 p.p.m. in February 2006. During 2006–2007, the LC50 was 3.84 p.p.m. at the start of the season and in March 2007 it was 13.51 p.p.m. The minimum LC50 of Indoxacarb was reported for H. armigera larvae fed on Legasca spp. (1.62 p.p.m.) and the maximum LC50 was reported for H. armigera reared on chickpea (Cicer arietium) (8.45 p.p.m.). LC50 of 2.73 and 4.56 p.p.m. were reported for H. armigera fed on cotton (Gossypium arborium) and pigeonpea (Cajanus cajan), respectively.
TL;DR: The effects of using tetracycline to eliminate Wolbachia on the oogenesis of its host uzifly Exorista sorbillans, a parasitoid of silkworm Bombyx mori L, results in a 20% reduction of fecundity.
Abstract: Maternally inherited bacteria of the genus Wolbachia are known to affect the physiology and reproduction of several arthropod and nematode hosts. This paper presents the effects of using tetracycline to eliminate Wolbachia on the oogenesis of its host uzifly Exorista sorbillans (Diptera: Tachinidae), a parasitoid of silkworm Bombyx mori L. Earlier we reported cytoplasmic incompatibility, nucleo-cytoplasmic conflict, male biased sex ratio and reduction in fecundity upon curing of Wolbachia infection using an antibiotic. This paper presents the abnormal growth and proliferation of oocytes in the uninfected/cured uziflies. The anomalies include abnormal/arrested oocyte production with inhibition of normal functioning of nurse cell nuclei, malformation and agglutination in egg chambers, empty egg chambers due to arrested vitellogenesis and undeveloped ovarian tubules. These anomalies further lead to reduction in growth of the ovarian tubules, which resulted in a 20 reduction of fecundity. It is hypothesized that normal oocyte production in uzifly requires the infection of Wolbachia bacteria. Further, in the uzifly, infection is at transition stage from a facultative to an obligatory mode of symbiosis. In light of this, this paper discusses the relationship between Wolbachia and oocyte production. © 2009 The Entomological Society of Korea and Blackwell Publishing Asia Pty Ltd.
TL;DR: Reciprocal crosses between resistant and susceptible populations were made to understand the population genetics of Indoxacarb resistance in H. armigera, and it was revealed that the inheritance of Indoxicarb resistance was autosomal: neither maternal effect nor linkage was evident.
Abstract: The present investigation was done with the aim of studying the genetics of Indoxacarb resistance. Selection of Helicoverpa armigera (Hubner) with Indoxacarb was done for eight generations to develop resistance. Reciprocal crosses between resistant and susceptible populations were made to understand the population genetics of Indoxacarb resistance in H. armigera. Generation-wise selection with Indoxacarb was evaluated for resistance development in H. armigera. The LC50 of Indoxacarb was 2.81 p.p.m. for the first selected generation, and it increased to 272.55 p.p.m. after eight selected generations, which is a 1238.86-fold resistance compared to the susceptible strain. The estimated realized heritability (h2) after eight generations of selection with Indoxacarb was 0.45. The number of generations required for a tenfold increase in LC50 (1/R) was estimated to be 2.59. The response to Indoxacarb selection in H. armigera was 0.39, the estimated selection differential (S) was 0.87, and the phenotypic standard deviation (σp) was 0.03. Reciprocal crosses between Indoxacarb resistant and susceptible strains revealed that the inheritance of Indoxacarb resistance was autosomal: neither maternal effect nor linkage was evident. The values of DLC (0.10 and 0.09) indicated completely recessive inheritance of Indoxacarb resistance.
TL;DR: The susceptibility of members of the Anopheles sinensis Group in Korea to insecticides was evaluated under laboratory conditions using 15 insecticides currently used by local public health centers in Korea and An.
Abstract: The susceptibility of members of the Anopheles sinensis Group in Korea to insecticides was evaluated under laboratory conditions using 15 insecticides currently used by local public health centers in Korea The insecticides included eight pyrethroids, six organophosphates and a pyrazol analogue Based on their LC50 values, the order of susceptibility of An sinensis larvae to the insecticides was bifenthrin, chlorfenapyr, α-cypermethrin and λ-cyhalothrin, with values of 0009, 004, 006 and 008 ppm, respectively The least susceptibility was obtained with fenitrothion, with an LC50 of 77 ppm In the comparative resistance test, the resistance ratios (RR) of 14 insecticides were compared to each other using two strains of members of the An sinensis Group collected in the locality in 2001 and 2008 Anopheles spp demonstrated higher RR to organophosphates such as fenthion, and low RR for the pyrethroids Among the organophosphates, fenthion had the highest RR of 333 and 2700 fold differences for LC50 and LC90 values, respectively Among the pyrethroids, permethrin was observed to have the highest RR of 38 and 18 fold differences for LC50 and LC90 values, respectively However, there were no significant differences in susceptibility to chlorfenapyr, chlorpyrifos, deltamethrin and fenitrothion An sinensis s l was more susceptible to the six insecticides bifenthrin, λ-cyhalothrin, α-cypermethrin, cypermethrin, cyfluthrin and pyridafenthion, showing 003, 006, 03, 03, 04 and 04 fold differences in resistance rates (RR LC50), respectively
TL;DR: Adult mosquito surveillance was conducted at two sites at Gijang‐gun, Busan southeastern area of the Korean peninsula, in 2004, and Armigeres subalbatus (Coquillett) was the most frequently collected mosquito at human‐landing collections followed by An.
Abstract: Adult mosquito surveillance was conducted at two sites at Gijang-gun, Busan southeastern area of the Korean peninsula, in 2004. The most frequently collected species at cow sheds were Anopheles sinensis sensu lato (s.l.) (83.4%), followed by Culex tritaeniorhynchus Giles (8.2%), Culex pipiens Coquillett (5.6%) and Aedes albopictus (Skuse) (2.4%). Adult populations of An. sinensis s.l. peaked during July (Trap Index, TI 1043.1), declining in August (TI 659.4) and September (TI 462.9) in 2004, while Cx. tritaeniorhynchus populations increased in August (TI 77.5) and September (TI 35.9). Adult Cx. tritaeniorhynchus was first collected in the second week of May (TI 4.0) and increased through August with two population peaks in the third week of July (TI 98.0) and the second week of August (TI 99.5). Armigeres subalbatus (Coquillett) was the most frequently collected mosquito at human-landing collections (30.4%) followed by An. sinensis s.l. (28.6%) and members of the Cx. pipiens complex (19.3%). Anopheles sinensis s.l. demonstrated two peaks of host-seeking activity at 22.00–23.00 hours and 02.00–03.00 hours in July, while in August the host-seeking peaks appeared at 22.00–23.00 hours and 03.00–04.00 hours. The black light trap collections of An. sinensis and Cx. tritaeniorhynchus demonstrated significant correlations to the ambient temperatures.
TL;DR: Pheromone trapping was used to monitor populations of the moth Helicoverpa armigera at five cotton‐based agro‐ecological sites – river, vegetable, orchard, forest and clean cultivation (areas under only cotton cultivation) – in the Bahawalpur district, Pakistan, and no model was found to be best fit by multiple linear regression analysis.
Abstract: Pheromone trapping was used to monitor populations of the moth Helicoverpa armigera at five cotton-based agro-ecological sites – river, vegetable, orchard, forest and clean cultivation (areas under only cotton cultivation) – in the Bahawalpur district, Pakistan. Three locations at each site were chosen and three pheromone traps at each location were installed in cotton fields. Moth catches were recorded at 15–20 day intervals from 24 October 2004 to 19 December 2006. In 2004, the river sites showed the maximum trapped population of H. armigera (0.22/trap) followed by 0.165 per trap at the vegetable sites. Orchard, clean cultivation and forest sites had zero moth catches. In 2005, the river sites again showed the highest trapped population (0.57/trap), followed by clean cultivation (0.45/trap), vegetable (0.44/trap), orchard (0.40/trap) and forest (0.29/trap). The moths appeared during July to December and March to May. In 2006, sites showed non-significant difference, with a population range of 0.47 to 0.97 moths per trap. On average, river sites peaked at 0.49 per trap, followed by vegetable (0.38), clean cultivation (0.47), orchard (0.35) and forest (0.25) sites. The peak was observed on 3 April 2006, and moths appeared during February to July and October to December. The minimum temperature in river, forest and clean cultivation sites; the maximum temperature in orchard sites; and the average temperature in river, orchard, forest and clean cultivation sites showed significant positive correlations with trapped moth populations. Relative humidity showed significant negative correlation with population at the orchard sites in 2005. All weather factors during 2004 and 2006 showed non-significant correlations with the moth populations. No model was found to be best fit by multiple linear regression analysis; however, relative humidity, minimum temperature, maximum temperature, minimum temperature and maximum temperature contributed 8.40, 10.23, 2.43, 4.53 and 2.53% to the population fluctuation of the moth at river, vegetable, orchard, forest and clean cultivation sites, respectively.
TL;DR: Pheromones are innate products, exploited for direct population manipulation in the trapping of precise pest density at five different cotton‐based agro‐ecological sites: river site, vegetable farm, orchard, clean cultivation site, and forest, which demonstrate feasibility and efficiency against Helicopverpa armigera.
Abstract: Pheromones are innate products, exploited for direct population manipulation in the trapping of precise pest density. They demonstrate feasibility and efficiency against Helicopverpa armigera at five different cotton-based agro-ecological sites: river site, vegetable farm, orchard, clean cultivation site, and forest. The data were recorded at 15–20 day intervals from 8 September 2004 to 1 December 2006. The Number of moths caught during the study period demonstrated that the vegetable farm showed the maximum population of moths per trap (0.54), followed by the orchard (0.29), forest (0.19), river (0.15), and clean cultivation site (0.12). During 2004, rainfall (in the orchard and clean cultivation site) and relative humidity (in the clean cultivation site) showed positive and significant correlation with the number of moths caught. During 2005, temperatures played a significant and positive role in population fluctuation of the pest almost at all the selected sites; the minimum temperature was recorded at the vegetable farm and the average temperature was found at the forest site. Rainfall also showed a significant and positive correlation with trapped moths in the vegetable farm, orchard, and clean cultivation site. During 2006, relative humidity showed a significant and negative correlation with the trapped population at all the sites except the river site. Rainfall showed a negative and significant correlation with the pest at the forest site. Relative humidity was the most important aspect at 8.93% causing variation in the trapped population followed by maximum temperature (5.7%), rainfall (1.63%), average temperature (0.74%), and minimum temperature (0.56%).