Национальная академия наук украины украинская академия наук

Автори вдячні за допомогу у визначенні видів і цінні консультації д. б. н. О. Г. Радченко (Інститут зоології ім. І. І. Шмальгаузена НАН України, м. Київ).

EVOLUTION OF AN ECOLOGICAL SYSTEM–FORMATIONS

W. Sierka, E. Sierka

Эволюция Экологической системы

В. Сиерка, E. Сиеркa

The work presents the results of investigations into the relationship between phases of development of mid-field shrub associations (Pruno–Crataegetum) and thrips communities (Thysanoptera) in the Jaworzno Hills area (the Silesian Upland, southern Poland).

In the past the area of the Jaworzno Hills was covered mainly by dry-ground forests, beech woods and mixed-coniferous forests, which were gradually stumped and turned into fields. Today most of the region’s arable lands are not cultivated, which is conducive to the development of mid-field shrubs; moreover, the fields are no longer subject to a regular agricultural treatment. Because of their high floral diversity (and rich food resources thus offered), which is enhanced by the transitional character of shrub associations between forest complexes and open fields, mid-field shrubs enrich the flora and fauna of deforested areas.

This project attempts to determine the relationship between the phase of development of mid-field shrub associations and the structure of thrips communities. Moreover, it aims to demonstrate that it is possible to use the parameters of the insect community structure in the evaluation of the distortion of plant associations.

Thrips were collected from patches of shrubs in different phases of development. Insects were identified to the species level and classified within main ecological groups as species connected with open areas, with forests, and ubiquitous forms. At the same time, phytosociological photographs were taken to determine the qualitative and quantitative composition of the phytocenoses.

The obtained data were analysed for particular developmental phases (initial, optimal and terminal) of mid-field shrubs, which were treated as stages of succession (the chronosequence approach).

On the basis of the zoocenotic indices calculated for particular thrips species, it was established that there is a straightforward correlation between the species composition of the plant associations and the structure of thrips communities. Moreover, an attempt was made to create a model which would represent the pattern of interdependence developing between the animal community and the type of plant association in relation to time and space. This model was then compared with zoocenoses of other plant associations – forest and meadow.

Basing on the results obtained from 27 patches of mid-field shrubs, a total of 52 plant species and 45 thrips species were found. As succession proceeds (successive developmental phases of the shrubs), the role of thrips of forest areas increases, while that of thrips living in open areas is minimised. In the initial phase of shrub development, the occurrence of one or several dominant species was recorded. These species play a major role in the formation of the structure of the community. Regarding the species composition, the terminal phase of shrub development resembles Querco–Fagetea forest associations.

It seems that mid-field shrubs are propagation centres for some thrips and function as environmental islands for forest species of this insect group.

The authors suggest that mid-field shrubs should be protected because of their importance for the conservation of natural habitat diversity, their contribution to the landscape and their biocenotic function (shrubs are a substitute for forests).

THRIPS GROUPINGS (INSECTA: THYSANOPTERA)

W. Sierka, W. Wojciechowski

ГРУППИРОВКИ ТРИПСОВ (INSECTA: THYSANOPTERA)

В. Сиерка, В. Войцеховский

Most of the research on thrips conducted in Poland has so far been concerned with the qualitative and quantitative composition of thrips fauna in agrocenoses as well as its influence on the growth of cultivated plants and cropping. The dependence of the species composition of thrips fauna on the structure of plant cover has been investigated by a few polish researches, among others, in xerothermic grass communities, dry-ground forests and thermophilous grass communities.

Relatively little research has been done on thrips living in various plant communities, which encouraged the present study conducted in the Jaworznickie Hills (Silesian Upland, southern Poland), an area representative enough to determine relationships between the structure of thrips associations and plant communities.

The Jaworznickie Hills, geologically highly diversified, cover an area of 510 km², their average altitude approximates 300 m above sea level. Most habitats potentially suitable for dry-ground forests, beech woods and mixed coniferous forests are now taken over by impoverished xerothermic grasses of the class Festuco–Bromete, arable lands and meadows (Arrhenatherion, Calthion, and Molinion), and pastures (Cynosurion), which degenerate as a result of drainage and transform into grass phytocenoses.

Material for the study was collected in selected plant communities of the Jaworznickie Hills in the years 1998–2000. Detailed analysis (a population profiles) was carried out in seven types of plant communities: I – Tilio–Carpinetum typicum, II – Querco roboris–Pinetum, III – Pruno–Crataegetum, IV – Trifolio–Agrimonietum, V – Koelerio–Festucetum sulcatae, VI – Molinietum medioeuropaeum, and VII – Arrhenatheretum medioeuropaeum.

For particular types of plant communities, Simpson’s species diversity coefficient was calculated (Simpson, 1949).

To determine the similarity of species composition in various zoocenoses, Sørensen’s coefficient was used (Sørensen, 1948).

In order to arrive at a more comprehensive and objective interpretation of the relationships between groups, Sørensen’s formula was additionally modified by substituting the number of species with the number of specimens (Górny & Grüm, 1981). In this way the total mathematical similarity between two sets was established, taking into account the number of individual elements which occurred in both sets.

The results of the analysis of groupings were presented graphically in a dendrogram. Moreover, the data were ordered by means of the principal component analysis (PCA).

During the three-year study in the examined area, 71 thrips species were collected by scooping, of which 53 represented the suborder Terebrantia, while the remaining 18 – the suborder Tubulifera.

Simpson’s species diversity coefficient was found to be highest in continental dry-ground forest and lowest in thermophilous communities on the outskirts of forests.

On the basis of Sørensen’s similarity coefficient, three groups of thrips were distinguished which inhabited specific types of plant communities. Group A comprises thrips of forest communities; group B includes thrips of outskirts of forests, shrub communities and xerothermic grasses; and group C – thrips found in meadow communities. And also the principal component analysis (PCA) produced three distinct types of groupings connected with different plant communities and habitats.

The species composition and proportion of thrips in the studied area are not typical of stable phytocenoses, as they are connected with plant communities to a considerable extent transformed by antropopressure. Changes in phytocenoses result in distortion of the related zoocenoses, which may be reflected in the decrease in the number of species, especially those rather rare, and the emergence of one or two dominant species, which prevail in the structure of the group. In the studied area three dominant species were found: Chirothrips manicatus Haliday, 1836 (connected with grasses), Aeolothrips intermedius Bagnall, 1934 (predacious) and Frankliniella intonsa (Trybom, 1895) (floricolous).

The mathematically calculated pattern of relations presented in the dendrogram and in the PCA graph-three groups of thrips (A, B, C) connected with specific plant communities – is reflected in the ecological analysis. This pertains in particular to group A (forests), where there was a considerable proportion of stenotopic species connected with bark and feeding on fungi (e. g. Hoplandrothrips bidens (Bagnall, 1910) and Phlaeothrips coriaceus Haliday, 1836).

Thus, it appears that the type of plant community is the main factor influencing the formation of thrips groupings in the area of the Jaworznickie Hills; however, the development of the plant community depends on many biotic and abiotic factors.

The study of species composition of thysanopterous fauna of various plant communities in Poland and similarities between insect groups connected with these communities is still under way. Detailed quantitative analyses of Thysanoptera contribute to our knowledge of long-term processes and spatial and temporal interactions within thrips fauna. To make such comparisons more reliable, further research on thrips is needed both in other regions of Poland and in Europe.

ФЕНОГЕНЕТИЧНА СТРУКТУРА РІЗНИХ ПОПУЛЯЦІЙ LEPTINOTARSA DECEMLINEATA (COLEOPTERA: CHRYSOMELIDAE) ІВАНО-ФРАНКІВСЬКОЇ ОБЛАСТІ

А. Г. Сіренко, А. Л. Єльцов

Прикарпатський національний університет ім. В. Стефаника, Україна,
E-mail: bratlibo@yahoo.co.uk

Ключові слова: Leptinotarsa, поліморфізм, популяція

FENOGENETIC STRUCTURE OF LEPTINOTARSA DECEMLINEATA (COLEOPTERA: CHRYSOMELIDAE) POPULATIONS

A. G. Sirenko, A. L. Yeltsov

Колорадський жук Leptinotarsa decemlineata Say, 1824 (Chrysomelidae, Coleoptera, Insecta) з точки зору популяційної генетики є дуже перспективним видом для вивчення мікроеволюційних процесів. Цей вид характеризується дуже складною популяційною структурою, високим рівнем поліморфізму популяцій, великим ареалом, інтенсивними міграційними процесами. Дослідження поліморфізму популяцій L. decemlineata триває майже 100 років. Їх розпочав Tower (1906). Найбільш детальні та глибокі дослідження поліморфізму цього виду проводили Ф. С. Кохманюк (1982) та А. Соколов (1979).

Вважається, що дослідження поліморфізму популяцій L. decemlineata актуальне з практичної точки зору – виявлено, що різні фени по-різному реагують на піретроїдні інсектециди. D. J. Hawthorne вважає, що гени, які відповідають за структуру забарвлення передньоспинки та чутливість до піретроїдних інсектицидів, пов’язані з Х–хромосомою, але ці гени досі не ідентифіковано.

Збір комах проводився в агроценозах на околицях м. Тлумач, м. Івано-Франківська, с. Павлівка (Тисменицький р-н), с. Майдан (Тисменицький р-н) з 1 по 10 серпня 2004 року. Проаналізовано популяції м. Тлумач – 237 екземплярів, м. Івано-Франківська – 183, с. Павлівка – 254, с. Майдан – 193 екземпляри комах. При обробці матеріалу класифікація фенів здійснювалась за Ф. С. Кохманюк (1982), використовувалась видозмінена формула Тауера. Для проведення порівняльного аналізу структур досліджених популяцій використаний критерій Пірсона. Для цього всю сукупність фенів розбито на групи: A, B, D, E, F, U(A), KLMP і було проведено порівняльний аналіз структур популяцій по цих групах фенів (табл.).

У досліджених популяціях вивлено наявність 47 основних елементів фенотипу (фенів), що зустрічаються з різною частотою. Виявлено фен Н, який ніколи досі не виявлявся у європейських популяціях – досі його знаходили тільки у північноамериканських популяціях. Відсутність цього фену пояснювали дрейфом генів (Кохманюк, 1982). З усіх досліджених досі популяцій виду L. decemlineata популяції Івано-Франківської області найбільш близькі до популяцій околиць м. Дніпропетровська. Загалом на території європейської частини колишнього СРСР виділяють чотири групи популяцій (Соколов, 1979; Кохманюк, 1982).

Таблиця. Відносна частота зустрічі фенів у популяціях Leptinotarsa decemlineata Say.