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52. Role of juvenile hormone in the hypermetabolic production of water revealed by the O2 consumption and thermovision images of larvae of insects fed a diet of dry food
- Creator:
- Karel Sláma and Jan Lukáš
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Lepidoptera, Galleria mellonella, Coleoptera, Dermestes vulpinus, Tribolium castaneum, Hemiptera, Pyrrhocoris apterus, O2 consumption, thermoregulation, heat dissipation, lipid-water conversion, 2, and 59
- Language:
- English
- Description:
- 1_The young larvae of insects living on dry food produce large amounts of water by the metabolic combustion of dietary lipids. The metabolic production of water needed for larval growth, previously known as hypermetabolic responses to juvenile hormone (JH), is associated with a 10- to 20-fold increase in the rate of O2 consumption (10,000 µl O2/g/h in contrast to the usual rate of 500 µl O2/g/h). Growing and moulting larvae are naturally hypermetabolic due to the endogenous release of JH from the corpora allata. At the last, larval-pupal or larval-adult moult there is no JH and as a consequence the metabolic rate is much lower and the dietary lipid is not metabolized to produce water but stored in the fat body. At this developmental stage, however, a hypermetabolic response can be induced by the exogenous treatment of the last larval instars with a synthetic JH analogue. In D. vulpinus, the JH-treated hypermetabolic larvae survive for several weeks without moulting or pupating. In T. castaneum and G. mellonella, the JH-treated hypermetabolic larvae moult several times but do not pupate. All these larvae consume dry food and the hypermetabolic response to JH is considered to be a secondary feature of a hormone, which is produced by some subordinated endocrine organ., 2_The organ is most probably the controversial prothoracic gland (PG), which is a typical larval endocrine gland that only functions when JH is present. According to our hypothesis, PG activated by JH (not by a hypothetical PTTH) releases an adipokinetic superhormone, which initiates the conversion of dietary lipid into metabolic water. This type of metabolic combustion of dietary lipid produces large quantities of endothermic energy, which is dissipated by the larvae in the form of heat. Thermovision imaging revealed that the body of hypermetabolic larvae of G. mellonella can be as hot as 43°C or more. In contrast, the temperature of "cold" normal last instar larvae did not differ significantly from that of their environment. It is highly likely that thermovision will facilitate the elucidation of the currently poorly understood hormonal mechanisms that initiate the production of metabolic water essential for the survival of insects that live in absolutely dry conditions., Karel Sláma, Jan Lukáš., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
53. Spatial and ecological isolation in cicadas: First data from Tibicina (Hemiptera: Cicadoidea) in France
- Creator:
- Sueur, Jerôme and Puissant , Stéphane
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Cicadidae, Tibicina, allopatry, habitat isolation, allochrony, human activity, and France
- Language:
- English
- Description:
- The seven taxa of the cicada genus Tibicina (T.corsica corsica, T. corsica fairmairei, T. garricola, T. haematodes, T. nigronervosa, T. quadrisignata, T. tomentosa) which occur in continental France and Corsica were investigated. Extrinsic factors (geographical barriers) and factors intrinsic to the ecology of species were considered in an effort to understand the biogeography of Tibicina. Three patterns related to intrinsic factors were recognised: (1) pairs of taxa with sympatric distributions but with divergent habitat preferences; (2) pairs of taxa with sympatric distributions and similar habitat but with allochronic occurrence; (3) pairs of taxa with similar ecology but with allopatric distributions. When taxa were separated by their habitat, the height of vegetation appeared to be more important than the floristic composition of the habitat. These factors lead to the partitioning of resources in time and space. All taxa occur in secondary vegetations. Human agro-pastoral activity has probably influenced the dynamics of cicada populations and the maintenance of isolation between them.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
54. Suitability of Bemisia tabaci (Hemiptera: Aleyrodidae) biotype-B and Myzus persicae (Hemiptera: Aphididae) as prey for the ladybird beetle, Serangium japonicum (Coleoptera: Coccinellidae)
- Creator:
- Tian, Mi, Wei, Yuling, Zhang, Shize, and Liu, Tongxian
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Aleyrodidae, Bemisia tabaci, cotton whitefly, Aphididae, Myzus persicae, green peach aphid, Coleoptera, Coccinellidae, Serangium japonicum, prey suitability, and biological control
- Language:
- English
- Description:
- The ladybird, Serangium japonicum (Coleoptera: Coccinellidae), is one of the most important predators of whiteflies in China, however, the suitability of different kinds of prey and nutritional requirements of this predator are poorly studied. The objectives of the present study were to investigate the pre-imaginal development, percentage survival of immatures, adult longevity and fecundity of S. japonicum when reared on two different species of prey, mixed ages of the cotton whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) biotype-B (i.e., eggs and nymphs) and green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) in order to quantify their relative suitability as prey under laboratory conditions of 25 ± 1°C, 50 ± 10% RH and a photoperiod of 16L : 8D. The results of this study indicate that the total developmental period (from egg to adult) was shorter when they were fed on B. tabaci (18.29 ± 0.13 days) than on M. persicae (19.85 ± 0.22 days). The percentage survival of the immatures, growth index, development rate, adult fresh weight, fecundity and percentage of eggs hatching were higher and the pre-oviposition period was significantly shorter when S. japonicum were fed on B. tabaci than on M. persicae. In contrast, there was no significant difference in their longevity and oviposition period when fed on B. tabaci and M. persicae. The results indicate that as a diet for S. japonicum M. persicae is inferior to B. tabaci. This is the first record of S. japonicum being able to complete its development feeding exclusively on M. persicae. Since B. tabaci and M. persicae often simultaneously occur in vegetable fields, these results indicate that it is likely that S. japonicum could be utilized to control mixed populations of aphids and whiteflies, and furthers our understanding of ladybird population dynamics in the field in relation to the availability of different species of prey.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
55. Survival and developmental characteristics of the predatory bug Orius similis (Hemiptera: Anthocoridae) fed on Tetranychus cinnabarinus (Acari: Tetranychidae) at three constant temperatures
- Creator:
- Zhang, Shi-Chang, Zhu, Fen, Zheng, Xia-Lin, Lei, Chao-Liang, and Zhou, Xing-Miao
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Anthocoridae, Orius similis, Acari, Tetranychidae, Tetranychus cinnabarinus, biological control, development characteristics, functional response, 2, and 59
- Language:
- English
- Description:
- Developmental characteristics of the predatory bug Orius similis fed on Tetranychus cinnabarinus were investigated at three constant temperatures (25, 28, and 31°C) under laboratory conditions (75±5% relative humidity and a 14L : 10D photoperiod). The survival of nymphs was highest at 28°C (75.57%) and at this temperature female adults O. similis had the longest oviposition period (21.1 d), the greatest fecundity (40.3 eggs) and the highest potential intrinsic rate of increase (rm: 0.108 d–1). These results suggest that O. similis can maintain greater population densities at 28°C than at the other temperatures tested. In addition, the functional response indicates that the attack rate of O. similis (1.04) and the maximum prey capacity (30.7 spider mites per bug in 24h) are greatest at 28°C. The results of this study provide useful information on the biology and time when to release O. similis in order to reduce the abundance of T. cinnabarinus in cotton fields., Shi-Chang Zhang ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
56. Temperature dependent functional response of Diaeretiella rapae (Hymenoptera: Aphidiidae) to the cabbage aphid, Brevicoryne brassicae (Hemiptera: Aphididae)
- Creator:
- Moayeri, Hamid R.S., Madadi, Hossein, Pouraskari, Hossein, and Enkegaard, Annie
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Aphidiidae, Diaeretiella rapae, Hemiptera, Aphididae, Brevicoryne brassicae, searching, handling time, functional response, biological control, 2, and 59
- Language:
- English
- Description:
- Diaeretiella rapae MacIntosh (Hymenoptera: Aphidiidae) is one of the most common and successful parasitoids of the cabbage aphid. The functional response of D. rapae towards cabbage aphids was examined in laboratory studies at three constant temperatures, 17°C, 25°C and 30°C. D. rapae exhibited a type II functional response at all three temperatures. The search rates were uninfluenced by temperature whereas handling times differed significantly between 17°C and 25°C, and between 17°C and 30°C, but not between 25°C and 30°C. This study is a first-step in the evaluation of the effectiveness of D. rapae as a biocontrol agent of Brevicoryne brassicae at different temperatures., Hamid R.S.Moayeri ... [et al.]., and Obsahuje seznam literarurty
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
57. Temperature-dependent development of dubas bug, Ommatissus lybicus (Hemiptera: Tropiduchidae), an endemic pest of date palm, Phoenix dactylifera
- Creator:
- Mokhtar, Abdul Monim and Nabhani, Salem Saif Al
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Ommatissus lybicus, dubas bug, date palm, lower thermal threshold, lethal high temperature, degree-days, and developmental rate
- Language:
- English
- Description:
- Dubas bug, Ommatissus lybicus Bergevin, is an important pest of date palm on the Arab peninsula. This sucking insect causes great damage to the trees and reduces the quantity and quality of the dates. Effect of temperature on the development of the immature stages of O. lybicus was studied in the laboratory by rearing them at nine constant temperatures, ranging from 15 to 35°C. Development was successfully completed at temperatures ranging from 20 to 35°C for eggs and from 20 to 32.5°C for nymphs. The lower thermal thresholds for development of eggs, nymphs and egg-adult were estimated by means of linear regression as 12.9, 12.9 and 13.2°C, respectively. Thermal units required for the development of the same stages were 572.5, 648.2 and 1184.4 degree-days, respectively. The lethal high temperatures were also estimated using a nonlinear model as 34.5, 43.4 and 34.6°C for eggs, nymphs and total immature stages, respectively. The development rate and survival data indicate that the optimum temperature range for O. lybicus is 25-27.5°C.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
58. Temperature-dependent functional response of Aenasius bambawalei (Hymenoptera: Encyrtidae) to different population densities of the cotton mealybug Phenacoccus solenopsis (Hemiptera: Pseudococcidae)
- Creator:
- Joodaki, Razieh, Zandi-Sohani, Nooshin, Zarghami, Sara, and Yarahmadi, Fatemeh
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, polokřídlí, Hymenoptera, Hemiptera, Encyrtidae, Aenasius bambawalei, Pseudococcidae, Phenacoccus solenopsis, attack rate, biological control, handling time, parasitoid, cotton mealybug, searching efficiency, 2, and 59
- Language:
- English
- Description:
- The functional response of Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) to different population densities of Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) was investigated under laboratory conditions of 65 ± 5% R.H., a photoperiod of 14L : 10D and at temperatures of 25, 30 and 35 ± 1°C. Two, 4, 6, 8, 16, 32 and 64 third instar nymphs of P. solenopsis were exposed to newly emerged mated female parasitoids for 24 h. The parasitoid exhibited a type II functional response at all temperatures. The searching efficiencies (a) and handling times (Th) were 0.1818 h-1 and 5.0012 h at 25°C, 0.1382 h-1 and 3.2807 h at 30°C, and 0.2097 h-1 and 2.3635 h at 35°C, respectively. The maximum attack rates (T/Th) were 4.8, 7.3 and 10.2 nymphs at 25, 30 and 35°C, respectively. This indicates that A. bambawalei is more likely to be an effective biological control agent of P. solenopsis in warm seasons., Razieh Joodaki, Nooshin Zandi-Sohani, Sara Zarghami, Fatemeh Yarahmadi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
59. The Cixiidae (Hemiptera: Fulgoromorpha) of the Mascarenes islands and Madagascar. Endemism and description of new taxa from Réunion with notes on their host plants
- Creator:
- Attié, Marc, Bourgoin, Thierry, and Bonfils, Jacques
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Fulgoromorpha, Cixiidae, Eumyndus, Achaemenes, Aselgeoides, Brixia, Oliarus, Cubana, Borbonomyndus gen. n., Meenocixius gen. n., Achaebana gen. n., new species, endemism, host-plant, Arecaceae, Pandanaceae, La Réunion, Rodrigues, and Madagascar
- Language:
- English
- Description:
- Two new species (Hemiptera, Fulgoromorpha, Cixiidae) included in a new genus, Meenocixius gen. n., and associated with Acanthophœnix rubra (Bory) H. Wendl. (Arecaceae) are described from the island of La Réunion: M. bebourensis sp. n. and M. virescens sp. n. This genus shows several autapomorphies in its tegmina venation, very particular within the Fulgoromorpha. Borbonomyndus gen. n., is proposed for another new species, B. pandanicola sp. n. associated with Pandanus purpurascens Thouars (Pandanaceae), and B. pallidus (Synave), previously described as a member of the genus Eumyndus Synave. According to morphological and ethological data, E. bistriatus is synonymized with B. pallidus, of which three different forms are recognized. All species of Borbonomyndus are found associated with Pandanus. These two new genera are endemic to La Réunion. Without taxonomic standing, the subspecies of Brixia belouvensis are synonymyzed and restricted to four different forms. A key is proposed for the Cixiidae of La Réunion, which now includes 12 species belonging to 6 different genera: Achaemenes, Aselgeoides, Brixia, Oliarus (but we show that the species placed in this genus need to be reviewed), Borbonomyndus, and Meenocixius. Monophyly of Eumyndus, from which E. perinetensis Synave is excluded, is substantiated. Following the new interpretation, this genus is now restricted to Madagascar. The species Cubana insularis Muir, from the island of Rodrigues, is transferred to a new genus: Achaebana gen. n. Finally, cixiid endemism and their host-plant associations in the Mascarenes are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
60. The ladybird beetle Harmonia axyridis (Coleoptera: Coccinellidae) as a possible predator of grape phylloxera Daktulosphaira vitifoliae (Hemiptera: Phylloxeridae)
- Creator:
- Kögel, Susanne, Schieler, Manuela, and Hoffmann, Christoph
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, Hemiptera, Phylloxeridae, Daktulosphaira vitifoliae, grapevine, Vitis vinifera, consumption, 2, and 59
- Language:
- English
- Description:
- 1_The ladybird beetle Harmonia axyridis (Pallas 1773) has been used for biological control in several countries. However, it became invasive in some of those countries. Coccinella septempunctata (Linné 1758) is a native species in Europe. It feeds mainly on aphids and can be very abundant. As far as is known there are no effective natural enemies of the grape phylloxera Daktulosphaira vitifoliae (Fitch 1855) in Europe. The potential of the above two ladybird species for reducing the abundance of the grapevine pest D. vitifoliae has not been previously investigated. In this study, the consumption and developmental parameters of H. axyridis and C. septempunctata fed on D. vitifoliae were determined in the laboratory. In a field trial, the occurrence of H. axyridis on grapevines with or without leaf galls of D. vitifoliae was compared. In contrast to C. septempunctata, H. axyridis was able to complete its development using D. vitifoliae as a source of food. In addition, adult H. axyridis consumed significantly more D. vitifoliae eggs than C. septempunctata. Within 24 h H. axyridis consumed up to 1400 eggs of D. vitifoliae. However, based on the fitness parameters "developmental time", percentage "survival" and "adult weight", this diet was less suitable for H. axyridis than the eggs of Ephestia kuehniella., 2_During field observations over a period of two years H. axyridis was repeatedly observed feeding on grape phylloxera leaf galls, which indicates that H. axyridis uses grape phylloxera as prey. H. axyridis was significantly more abundant on leaves with leaf galls of D. vitifoliae than on leaves without galls. C. septempunctata was rarely found on grape leaves with or without leaf galls. These results indicate that overall H. axyridis, unlike C. septempunctata, is a predator of D. vitifoliae and could potentially reduce grape phylloxera numbers in vineyards., Susanne Kögel, Manuela Schieler, Christoph Hoffmann., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public