|
| |
|
|
Wing reduction in cockroaches (Blattaria)
Kotyk, Michael ; Kotyková Varadínová, Zuzana (advisor) ; Nedvěd, Oldřich (referee)
My bachelor thesis deals with the wing reduction in cockroaches and the causes of its appearance. Order Blattaria is the insect order with the third highest occurrence of apterous and brachypterous species. Yet still only a minimum of publications were performed to cover this topic. Therefore, I analyse in several chapters both the types of wing reduction as well as generally accepted theories explaining the reasons of its evolution in insects. Then I discuss their relevance in the case of order Blattaria. Namely, ecological theories, regarding interactions of insect and its habitat, and physiological theories, describing life history trade- offs and constrains related to wings. I present examples of species to every theory which are probably concerned. There are also examples of species which maintain the macropterous state, although no longer capable of flight and theories that explain the retention of macroptery. As a part of the thesis I have also included a phylogenetic tree of cockroaches with marked wing condition for each sex, which outlines evolutionary trends of individual groups within the order. Keywords: Blattaria, reduction, macroptery, brachyptery, aptery, habitat, life history trade-offs
|
|
|
Pheromonal communication in precopulatory behaviour of bumblebees (Hymenoptery, Apidae, Bubmus).
Hovorka, Oldřich ; Král, David (advisor) ; Stejskal, Václav (referee) ; Nedvěd, Oldřich (referee)
XIII. ZÁVĚR 1 + 2) Bylo jednoznačně prokázáno, že čmelák klamavý (B. confusus) není v rámci rodu Bombus svou prekopulační strategií vyjímečný a že není druhem, jehož samci nepoužívají feromon k získání partnerek. Složení jeho samčího značkovacího feromonu bylo detailně popsáno stejně jako jeho prekopulační strategie, která plně odpovídá ostatním druhům se strategií číhání (perching behavior). 3) Analýzou samčího značkovacího feromonu bylo u vzorků získaných v různých částech ČR v rozdílných biotopech a nadmořských výškách prokázáno, že z druhové skupiny čmeláka hájového (B. lucorum) je dominantním a jediným v testovaných vzorcích přítomným druhem právě druh B. (s. str.) lucorum (L., 1761). Zbylé dva druhy, dříve hlášené z území ČR, jsou zde pravděpodobně vzácné a potvrzení jejich výskytu na našem území je jedním z úkolů do dalších let výzkumu. 4) U čmeláka ovocného (B. pomorum) bylo jako u prvního zástupce podrodu Rhodobombus popsáno složení samčího značkovacího feromonu. To je v rámci celého rodu Bombus unikátní absencí obvykle přítomných těkavých látek. To spolu se silnou redukcí hlavové části labiální žlázy a celkově nízkou dávkou i koncentrací přítomných, málo těkavých uhlovodíků vyvolává otázky, zda je prekopulační strategie tohoto druhu zcela shodná s ostatními patrolujícími druhy, mezi které je...
|
|
|
Pheromonal communication in precopulatory behaviour of bumblebees (Hymenoptery, Apidae, Bubmus).
Hovorka, Oldřich ; Král, David (advisor) ; Stejskal, Václav (referee) ; Nedvěd, Oldřich (referee)
XIII. ZÁVĚR 1 + 2) Bylo jednoznačně prokázáno, že čmelák klamavý (B. confusus) není v rámci rodu Bombus svou prekopulační strategií vyjímečný a že není druhem, jehož samci nepoužívají feromon k získání partnerek. Složení jeho samčího značkovacího feromonu bylo detailně popsáno stejně jako jeho prekopulační strategie, která plně odpovídá ostatním druhům se strategií číhání (perching behavior). 3) Analýzou samčího značkovacího feromonu bylo u vzorků získaných v různých částech ČR v rozdílných biotopech a nadmořských výškách prokázáno, že z druhové skupiny čmeláka hájového (B. lucorum) je dominantním a jediným v testovaných vzorcích přítomným druhem právě druh B. (s. str.) lucorum (L., 1761). Zbylé dva druhy, dříve hlášené z území ČR, jsou zde pravděpodobně vzácné a potvrzení jejich výskytu na našem území je jedním z úkolů do dalších let výzkumu. 4) U čmeláka ovocného (B. pomorum) bylo jako u prvního zástupce podrodu Rhodobombus popsáno složení samčího značkovacího feromonu. To je v rámci celého rodu Bombus unikátní absencí obvykle přítomných těkavých látek. To spolu se silnou redukcí hlavové části labiální žlázy a celkově nízkou dávkou i koncentrací přítomných, málo těkavých uhlovodíků vyvolává otázky, zda je prekopulační strategie tohoto druhu zcela shodná s ostatními patrolujícími druhy, mezi které je...
|
|
| |
|
|
The food preferences of asian lady beetle Harmonia axyridis
Šenkeříková, P. ; Nedvěd, Oldřich
Survey of food preferences of Asian ladybird Harmonia axyridis included two-choice and no-choice tests. Wingless females of aphids Acyrthosiphon pisum, Aphis fabae cirsiiacanthoidis and Aphis sambuci were offered to twenty-four hours starving ladybirds. No-choice tests we conducted only with adults. We gave them 20 individuals of one aphid species and we found that ladybirds fed most number of A. pisum. In two-choice test, we combined pairs of studied species: A. f cirsiiacanthoidis x A. pisum, A. pisum x A. sambuci, A. sambuci x A. f cirsiiacanthoidis. We put 10 aphids of each of the two species combined into a plastic Petri dish and then we introduced one ladybird adult or larva. We made 20 replicates with adults. We found that there was statistical difference only in the combination A. sambuci vs. A. f cirsiiacanthoidis, where males consumed more individuals of the toxic aphid A. sambuci. For this combination, we then made 20 replicates with larvae who preyed in contrast with males more of the suitable food A. f cirsiiacanthoidis than toxic A. sambuci. We also studied the influence of contrasting background on food choice in adults. We used both tests and all combinations. We found that females did not prefer any aphid species, except for the black A. f cirsiiacanthoidis being consumed more often than the green A. pisum on black background. Because they consumed much more A. pisum in no-choice experiment on both backgrounds, the difference in choice experiment is very strong and its polarity surprising.
|
|
|
Diversity of cockroach mating behaviour (Blattodea: Blaberidae)
Dvořák, Tomáš ; Kotyková Varadínová, Zuzana (advisor) ; Nedvěd, Oldřich (referee)
Mating behaviour of cockroaches is spectacular phenomenon with three different mating patterns traditionally distinguished. The most common and probably ancestral is type A - female climbing. Then it is type B - male climbing and type C - no climbing. Mating type was described in around 30 Blaberidae species. As it is the only cockroach family where all three types are present, it is an interesting model group for studying evolutionary questions. The main goal of the thesis was detail exploration and description of mating sequences in 21 Blaberidae species, 17 of which haven't been examined in this aspect before. An intrageneric diversity in mating patterns (genus Pycnoscelus) was described for the first time. Moreover, in case of P. tenebrigera, it was not possible to assign its mating pattern to any of the three traditional types. Multidimensional statistical analysis and biological interpretation of qualitative behavioural elements revealed two well separated clusters of mating sequensces. Consequently, we propose to distinguish only two types of mating pattern - ancestral type (identical with type A) and derived type. We also discussed the relationship between wing reduction and occurence of derived mating types. Evaluation of quantitative behavioural elements revealed positive correlation between...
|
|
|
The influence of chemical stimuli on the behaviour of the cockroach Amazonina platystylata (Blattodea: Ectobiidae)
Jůna, František ; Kotyková Varadínová, Zuzana (advisor) ; Nedvěd, Oldřich (referee)
Cockroaches are not considered typical plant pollinators, however, there are some exceptions to this rule. One of them is the South American species Amazonina platystylata, which is known for pollinating a dioecious shrub Clusia blattophila. This clusia is quite abundant on the Nouragues inselberg in French Guyana and is endemic there. In my research I was focused on the plant-animal communication. The aim of this thesis was to find possible behavioural response to the flower scent of clusia or to the compounds of flower scent, as clusia flowers differ in compounds of scent. Male flowers produce acetoin as a major compound. This compound is also found in female flowers but only at lower levels and in the first night of flowering. When acetoin was added to two days old female flowers, the amount of cockroaches' visits in such flowers increased to the same level as observed on male flowers. Until now there were no records about biology of this cockroach species and neither was morphology of their glands described. I have found out that both males and females of A. platystylata have tergal modification on the 7th to 8th tergite; a modification that could be connected to their glands. Evaporation plate on the first tergal shield in A. platystylata is described in this thesis for the first time. Key...
|
|
|
Wing reduction in cockroaches (Blattaria)
Kotyk, Michael ; Kotyková Varadínová, Zuzana (advisor) ; Nedvěd, Oldřich (referee)
My bachelor thesis deals with the wing reduction in cockroaches and the causes of its appearance. Order Blattaria is the insect order with the third highest occurrence of apterous and brachypterous species. Yet still only a minimum of publications were performed to cover this topic. Therefore, I analyse in several chapters both the types of wing reduction as well as generally accepted theories explaining the reasons of its evolution in insects. Then I discuss their relevance in the case of order Blattaria. Namely, ecological theories, regarding interactions of insect and its habitat, and physiological theories, describing life history trade- offs and constrains related to wings. I present examples of species to every theory which are probably concerned. There are also examples of species which maintain the macropterous state, although no longer capable of flight and theories that explain the retention of macroptery. As a part of the thesis I have also included a phylogenetic tree of cockroaches with marked wing condition for each sex, which outlines evolutionary trends of individual groups within the order. Keywords: Blattaria, reduction, macroptery, brachyptery, aptery, habitat, life history trade-offs
|
|
|
Harlequin ladybird (Harmonia axyridis) – biocontrol agent or biodiversity threat?
Nedvěd, Oldřich
This certified methodics for practical use describes spreading of an invasive species of predator of aphids in the Czech Republic and in Europe, provides a tool for identification of several developmental stages, describes pest control in various agroecosystems by the ladybird and reduction methods of the ladybird in plant cultures and houses. Decrease of biodiversity of insect predators by the aggresive ladybird, methods of sampling and rearing are described.
|
guest ::
