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41. Implications of insect responses to supernormal visual releasing stimuli in intersexual communication and flower-visiting behaviour: a review

Creator:
Kral, Karl
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, hmyz, motýli, čmelák, opylovači, insects, butterflies, bumble bees, pollinators, visual stimuli, mating, foraging, orchid mimicry, food reward, floral size, floral symmetry, ultraviolet signals, 2, and 59
Language:
English
Description:
Animals, including human beings, tend to respond more strongly to stimuli that are associated with the highest relative rewards. This applies not only to food rewards but also to reproductive success. In the present review article this issue is discussed for insects in connection with intersexual communication and flower-visiting behaviour. Implications of the preference for supernormal visual releasing stimuli are examined from a sensory and evolutionary perspective, including a consideration of the choice of potential mates and recognition of the most rewarding flowers., Karl Kral., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

42. Insect cold tolerance: How many kinds of frozen?

Creator:
Sinclair, Brent J.
Format:
print, text, and regular print
Type:
article, bibliography, conference publication, model:article, and TEXT
Subject:
Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, tolerance k chladu, tolerance k mrazu, netolerance k mrazu, teplotní strategie, 591.5, 061.3, and 595.2/.7
Language:
English
Description:
Insect cold tolerance mechanisms are often divided into freezing tolerance and freeze intolerance. This division has been criticised in recent years; Bale (1996) established five categories of cold tolerance. In Bale's view, freezing tolerance is at the extreme end of the spectrum of cold tolerance, and represents insects which are most able to survive low temperatures. Data in the literature from 53 species of freezing tolerant insects suggest that the freezing tolerance strategies of these species are divisible into four groups according to supercooling point (SCP) and lower lethal temperature (LLT): (1) Partially Freezing Tolerant-species that survive a small proportion of their body water converted into ice, (2) Moderately Freezing Tolerant-species die less than ten degrees below their SCP, (3) Strongly Freezing Tolerant-insects with LLTs 20 degrees or more below their SCP, and (4) Freezing Tolerant Species with Low Supercooling Points which freeze at very low temperatures, and can survive a few degrees below their SCP. The last 3 groups can survive the conversion of body water into ice to an equilibrium at sub-lethal environmental temperatures. Statistical analyses of these groups are presented in this paper. However, the data set is small and biased, and there are many other aspects of freezing tolerance, for example proportion of body water frozen, and site of ice nucleation, so these categories may have to be revised in the future. It is concluded that freezing tolerance is not part of Bale's (1996) continuum, but rather a parallel, alternative strategy of cold tolerance., Brent J. Sinclair, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

43. Insemination and fertilization in the seed bug Lygaeus simulans (Heteroptera: Lygaeidae)

Creator:
Micholitsch, Thomas, Krügel, Peter, and Pass, Günther
Format:
print, text, and regular print
Type:
article, model:article, and TEXT
Subject:
Lygaeidae, kopulace, entomologie, hmyz, ploštice, Lygaeus simulans, kopulační orgány, morfologie, inseminace, fertilizace, Heteroptera, genitalia, copulation, cryptic female choice, sperm utilization, spermatheca, aedeagus, processus gonophori, insemination, fertilization, 595.2/.7, and 591.4
Language:
English
Description:
In the laboratory, not all females of the seed bug Lygaeus simulans Deckert, 1985, produced fertilized eggs after copulation: 26.7% of the females were not inseminated and 5% were inseminated but did not lay fertilized eggs; only in 40% of the couples did copulation result in fertile eggs. The remaining 28.3% of couples refrained from mating. Duration of copulation was associated with insemination and fertilization: (i) fertile eggs were produced by only one couple that copulated for less than 60 min and all those that copulated for more than 360 min, (ii) probability of fertilization increased steadily with duration of copulation between 60 and 360 min, and (iii) duration of copulation was significantly different for couples that showed different insemination status. A possible morphological explanation for this rime dependency was revealed by examining the genitalia of 69 couples freeze-fixed in copula after different periods in copulation. Because of the intricate structure of the genitalia in L. simulans, a male takes a long time to manoeuver its intromittent organ into the narrow insemination duct of the female. Only if completely inserted is the tip of the intromittent organ close enough for successful ejaculation of sperm into the spermatheca. The freeze-fixing experiment revealed that it usually took the male more than 30 min to locate the entrance to the insemination duct and another 30 min for full penetration. This explains why copulations that lasted less than 60 min failed, since insemination began only after intromission was complete. The experiments, therefore, indicated that there is a relationship between the complex morphology of the genitalia and the low rates of insemination and fertilization in L. simulans., Thomas Micholitsch, Peter Krügel, Günther Pass, 7 obrázků, 1 tab., and Lit.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

44. Intracellular calcium in PTTH-stimulated prothoracic glands of Manduca sexta (Lepidoptera: Sphingidae)

Creator:
Birkenbeil, Heiner
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, fyziologie živočichů, hmyz, motýli, Sphingidae, Manduca sexta, prothorakální žlázy, ekdysteroidy, syntéza, stimulace, vápník, 595.2/.7, and 591.1
Language:
English
Description:
Larval Manduca prothoracic gland cells in vitro responded to prothoracicotropic hormone (PTTH) from neurosecretory cells of the brain with an increase of intracellular free calcium. This effect is reversible and dose-dependent. Preincubation of the glands with TMB-8 and dantrolene, which inhibit the release of calcium from intracellular stores, did not decrease the PTTH-stimulated increase in calcium, indicating that intracellular calcium stores are not involved in the control of ecdysteroidogenesis. Pharmacological studies of the PTTH effect with calcium channel blockers revealed that the increase in calcium was totally blocked by cadmium, partially inhibited by nickel and lanthanum and by amiloride, an antagonist of T-type calcium channels. All other inhibitors tested were ineffective, suggesting that the increase in cytosolic calcium is induced by opening of calcium channels, presumably of the T-type, in response to PTTH. The action of PTTH on these channels may be mediated by a G-protein as shown by the effect of mastoparan, a G-protein activator, which increased the concentration of cytosolic calcium comparable to that evoked by PTTH., Heiner Birkenbeil, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

45. Íránští tesaříci rodu Purpuricenus

Creator:
Simandl, Jiří
Format:
print
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, hmyz, tesaříkovití, insects, long-horned beetles, Írán, 2, and 59
Language:
Czech
Description:
Článek shrnuje dosavadní znalosti o druhové diverzitě, bionomii a rozšíření rodu Purpuricenus (Coleoptera, Cerambycidae) na území Íránu s dílčími poznámky o jejich výskytu a ekologii., The article summarises recent knowledge related to the diversity, bionomy and distribution of species of the genus Purpuricenus (Coleoptera, Cerambycidae) in Iran. Some previously less known occurence data and ecological notes are briefly mentioned., and Jiří Simandl.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

46. Jak reagují společenstva mravenců na změny prostředí

Creator:
Pavel Pech
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, hmyz, bezobratlí, životní prostředí, ekologie, insects, invertebrates, environment, ecology, 2, and 59
Language:
Czech
Description:
Společenstva mravenců většinou reagují na změny jejich biotopů méně výrazně než společenstva jiných organismů. V biotopech měnících se pozvolněji (např. neobhospodařované louky) se zpravidla dlouho zachovává původní druhová skladba myrmekofauny, zatímco výměna druhů z jiných skupin (rostlin i většiny bezobratlých) je mnohem rychlejší. Podobně na člověkem výrazně pozměněných lokalitách typu výsypek, odkališť nebo pískoven společenstvo mravenců velmi často sestává pouze z několika běžných druhů, zatímco mezi ostatními organismy se obyčejně najde řada druhů z Červené knihy. Mezi příčiny těchto rozdílů patří zejména značná schopnost mravenců regulovat podmínky panující v hnízdě, jejich agresivita a způsob šíření. Nově vzniklou lokalitu nejrychleji osídlí druhy mravenců běžné v okolí, kdežto obecně vzácnější specialisté mají zpoždění a již existující kolonie dříve příchozích je na lokalitu nepustí. Na druhou stranu z výskytu kolonií druhů na místech pro ně nevhodných může ukazovat, že na těchto lokalitách panovaly v uplynulých letech podmínky odlišné., Ant assemblages are usually less affected by environmental alteration than other organisms. They persist without obvious changes in slowly changing habitats (e.g. unmanaged meadows) much longer than assemblages of plants or most invertebrates. Similarly, communities of ants consist of several common species in anthropoge­nic habitats (spoil dumps, coal ash settling basins or sandpits) whereas assemblages of other organisms usually contain some rare and endangered species. The ability of ants to regulate environmental conditions in nests, their agressivity and mode of dispersion play an important role in this re­spect. A new locality is often first colonised by common ant species. The occurrence of colonies of certain species in habitats with suboptimal conditions can indicate the past changes of local environmental conditions., and Pavel Pech.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

48. Juvenile hormone synthesis by corpora allata of tomato moth Lacanobia oleracea (Lepidoptera: Noctuidae), end the effects of allatostatins and allatotropin in vitro

Creator:
Audsley, Neil, Weaver, Robert J., and Edwards, John P.
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, fyziologie živočichů, hmyz, motýli, Noctuidae, Lacanobia oleracea, corpora allata, juvenilní hormony, biosyntéza, kontrola biosyntézy, neuropeptidy, allatostatiny, allatotropiny, účinky, pokusy in vitro, 595.2/.7, and 591.1
Language:
English
Description:
The nature and rate of juvenile hormone (JH) biosynthesis and effects of allatostatins and allatotropin have been investigated in isolated corpora allata (CA) of adults and larvae of the noctuid tomato moth, Lacanobia oleracea. In adult female CA, mean rates of synthesis were relatively constant (10-16 pmol/pr/h) at all times. However, the range of JH synthesis by individual CA of similarly aged insects was quite large (2-30 pmol/pr/h). High performance liquid chromatography (HPLC) separation shows that adult female moth CA synthesise predominantly JH I and JH II. Rates of JH synthesis in vitro are dependent on methionine concentration. Synthetic Manduca sexta allatostatin (Mas-AS) caused a dose-dependent inhibition of JH synthesis by adult female CA but only to a max. of 54%, whilst 10 µM synthetic M. sexta allatotropin caused a 37% stimulation of CA activity. At 1 mM the cockroach allatostatin, Dip-allatostatin-2, had no significant effect on JH synthesis. In larval L. oleracea, rates of JH biosynthesis were very low., Neil Audsley, Robert J. Weaver, John P. Edwards, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

49. Kdo je v pasti, aneb problémy sběru terénních dat o hmyzu

Creator:
Knapp, Michal
Format:
print, bez média, and svazek
Type:
article, text, články, journal articles, model:article, and TEXT
Subject:
Biologické vědy, hmyz, biodiverzita, sběr dat, ekologický výzkum, insects, biodiversity, data collection, ecological research, sběr terénních dat, terénní data, funkční diverzita, pasti, sběr hmyzu, field data, 2, and 57/59
Language:
Czech
Description:
Vybrat vhodnou metodu sběru hmyzu tak, aby byla efektivní a přitom poskytovala relevantní data, není vůbec snadné. Na základě rozsáhlého datového souboru se ukázalo, že zemní pasti, standardně používaná metoda při ekologickém výzkumu epigeických členovců, zaznamenaly jen polovinu druhů střevlíků ve srovnání s metodou individuálního sběru. Výrazně se lišily i vlastnosti zaznamenaných druhů, v pastech převládaly druhy velké, kdežto ve vzorcích z individuálního sběru druhy drobné. Ale i metoda individuálního sběru má své mouchy, protože její účinnost do značné míry závisela na terénních zkušenostech sběratele. Ideálním řešením zajišťujícím co nejkompletnější záznam společenstev střevlíků se zdá být kombinace obou metod sběru dat., The selection of a proper sampling technique for ecological research into insect assemblages is a tough nut to crack. Based on extensive field study, I have shown that the commonly employed "pitfall trapping" technique recorded just half the number of carabid species compared to the individual collection technique. There were also differences in species trait representation in samples originating from each particular technique. Pitfall traps efficiently recorded large species but missed smaller ones, which were frequently recorded by individual collection. The main shortcoming of the individual collection technique is the dependence of its efficiency on the field experiences of each particular researcher. A combination of both investigated sampling techniques seems to be the best way to gain as complete records of carabid assemblages as possible., and Michal Knapp.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

50. Kterak se do vinic život vraceti začal. Historie ekologického vinohradnictví na jižní Moravě /

Creator:
Hluchý, Milan,
Type:
text and studie
Subject:
Zemědělství. Pedologie. Agrotechnika. Agroekologie, vinohradnictví, vinohrady, zemědělství ekologické, ekologie, pesticidy, hmyz, Československo 1945-1992, české země od r. 1993 do současnosti, zemědělství, rybníkářství, lesnictví, myslivost, and vědy o živé přírodě
Language:
Czech
Description:
How life began to return to the vineyards. History of organic viticulture in South Moravia.
Rights:
unknown