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Start Over Subject Zoologie Subject brouci

31. Stanovištní činitele ovlivňující rozšíření brouků vázaných na mrtvé dřevo

Creator:
Jakub Horák
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, brouci, mrtvé dřevo, lesní ekosystémy, 2, and 59
Language:
Czech
Description:
Saproxylic beetles are one of the most studied groups of organisms. This article summarize the key habitat featuresposition, insolation, diameter, decay stage and tree species – which influence the general distribution of beetles dependent on dead wood. and Jakub Horák.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

32. Trophic induction of diapause in native and invasive populations of Harmonia axyridis (Coleoptera: Coccinellidae)

Creator:
Ovchinnikova, Antonina A., Ovchinnikov, Andrey N., Dolgovskaya, Margarita Yu., Reznik, Sergey Ya., and Belyakova, Natalia A.
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, brouci, slunéčkovití, slunéčko východní, beetles, Coccinellidae, Harmonia axyridis, Coleoptera, photoperiod, diet, diapause, invasion, 2, and 59
Language:
English
Description:
Ovipositing females from invasive (Krasnodar Territory of Russia) and native (Far East of Russia) populations of Harmonia axyridis were fed one of a set of diets ranging from 50 Myzus persicae aphids every day to 1 aphid every 10 days and all were also provided with a 10% sugar solution. The experiment was conducted at 20°C under short (12 h) and long (18 h) day conditions. Most of the females from the native population that consumed 50 or 10 aphids per day continued to oviposit under both long and short day conditions. Females that consumed 1 aphid per day or every 2 days practically stopped laying eggs but under long day conditions their ovaries were still active, whereas under short day conditions ca 50% of them were reproductively inactive (only germaria present) and had a well-developed fat body. Further reduction in diet resulted in an increase in the proportion of reproductively inactive females. However, about half of the females that terminated oogenesis under long day conditions had poorly developed fat bodies, which indicates that diapause was not induced. For the females from the invasive population, both photoperiodic and trophic effects were weak: under short day conditions, some females entered diapause when prey was abundant, whereas about 50% (independent of photoperiod) did not enter diapause when starved. This risk-spreading strategy, possibly, facilitates the adaptation of this invasive ladybird to unpredictable environmental conditions., Antonina A. Ovchinnikova, Andrey N. Ovchinnikov, Margarita Yu. Dolgovskaya, Sergey Ya. Reznik, Natalia A. Belyakova., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33. Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)

Creator:
Price, Thomas N., Leonard, Aoife, and Lancaster, Lesley T.
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, brouci, mandelinkovití, beetles, Chrysomelidae, Coleoptera, Bruchinae, Callosobruchus maculatus, emerging crop pests, host shifts, genetic variation, adaptation trajectory, evolvability, experimental evolution, quasi-natural selection, heritability, 2, and 59
Language:
English
Description:
Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests., Thomas N. Price, Aoife Leonard, Lesley T. Lancaster., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public